Hi, I have a 2000 dodge dakota with a four channel sony amp that puts out 75 watts rms to four speakers that are rated to take up to 90 watts rms each; and a bazooka mono sub amp that puts out 500 watts rms at 2 ohms connected to 2 sony subs that are rated at 250 watts rms each, wired in parallel.
My problem is that my amps are cutting out when I drive slow, and kick back on when I drive over 55mph, or when I rev my engine a lot in neutral.
A friend of mine told me that it could have something to do with my remote turn-on being daisy chaned from one amp to the other, and that the truck (or cd player) isn't providing enough power threough the remote turn-on to keep the amps on. He also said that there's something I could buy at radio shack that will keep a constant power supply to the remote turn-on wire.
I called crutchfield and asked them about it and they said I should just have to get a capacitor, so I did, and I'm still having the same problem.
The amps stay on longer if I leave the radio off while driving the first few miles, or if I turn the subbs off with the cd player, but they'll still eventually turn off.
Does any one know what could be the problem?
I already know that the amps are not over heating since they'll shut off right away if I turn the radio on right away and then they'll kick on later.
Any help is greatly appreciated.
Thanks,
Alan LaMore
Replies (22)
ttocs on 11/26/2003 21:18:14
ok, don't call them anymore...
I had a simalar situation in a vehicle we worked on years ago. You didn't mention that there was a aftermarket HU? that was the case in this care. We tapped into what we thought was a switched ignition wire at the fusebox for the remote wire, it was for the cruise control infact. It would come on and off above and below a certain MPH. It cracked us up at the time as we thought the dude was nutz.....
I have to say that it has to do with the remote wire, but we need to test it to be sure. Do you have a testlight or voltmeter? You need to hook one up to the remote wire and simulate these conditions to see what the voltage is doing. Maybe take a freind with you to watch it while you drive, don't do anything unsafe/stupid.... If that stays at +12v we need to do the same with the constant.
You do not want to add anything to keep the remote turn on, on all the time. Your amps would not shut off, your battery would die...
alanjlamore on 11/26/2003 21:25:07
Yes, the HU is an alpine CDM-9801.
I can get a multimeter from where I work, and I will test to see if there's 12 volts comming out of the remote or not, but what do I do if there's not 12v comming out when it cuts off; and what should I do if there is?
I'm guessing that the voltage is dropping from the remote wire, but I'll test to make sure.
Thanks for the quick response,
Alan LaMore
alanjlamore on 11/26/2003 21:54:40
I just remembered that my friend was talking about installing a relay, but I don't know what kind to get, or how to install it.
Any suggestions?
cplkittle on 11/27/2003 09:46:49
What a relay does is take a small voltage to open a switch that allows higher voltage to pass through. It is like a flip switch except instead of you flipping it on, the remote wire from your stereo provides the voltage necessary to turn it on. Your friend is thinking that your remote wire is not providing the voltage necessary to tell the amps to come on.
If this is the problem, you can get one from radio shack. Tell them what you are doing, they should be able to help you. Make sure you get one rated higher than the combined total of the amps your amplifiers are pulling.
I have never seen this as a problem before, but I could be wrong. I am running a 600w amp and a 200w amp plus 2 neon lights with my remote wire. (when I say running the amps I mean as a remote, not a main source of power)
ttocs on 11/27/2003 20:34:27
I have seen it happen. If you want to test this theory, hook you remote wire going to your amps, to the +12v switched wire(red). It will provide enough current for the amps.
Relays are not all that hard, I can get you through it if we need to. I can always prewire one and ship it to you as well.
alanjlamore on 11/28/2003 08:51:53
If you could get me the kind of relay I need, and could tell me exactly where to wire it to, I'd be more than happy to pay you for the relay and a little extra for the install advice.
I have a paypal account and would prefer to do it that way if you have one too.
Let me know if you'd be able to or not.
BTW, I don't know if you need this info or not, but my sony amp is a 75w rms X 4 channels, and my mono sub amp puts out 500w rms when wired for 2 ohms. They're in a 2000 Dodge Dakota.
Thanks,
Alan LaMore
cinci23 on 12/4/2003 13:13:00
Hey Alan. What kind of wiring kit do you have. i have a sony amp and at first I was thinking overheating because mine did that. What it sounds like though is your amp is definately not getting enough power. This can be attributed to your wiring kit. I dont know anything about a remote relay though. Just that when you rev your car you get more power, that is saying that your are not getting enough initially. So I am wondering about your wiring kit. Later. Nick
alanjlamore on 12/13/2003 22:08:26
The wiring kit I have uses a 4 guage wire going from the battery to a distribution block, and has two 8 guage wires going to each amp. The wires are more than thick enough for the power.
I started realizing that the amps will kick back on when I hit the brake, or when the doors lock (happens automatically when I reach 15 mph).
Sometimes they kick on while I'm stopped at a light, and other times they won't. The amps are not overheating, because it happens right when I start the truck, and sometimes they stay on for a long time.
I think it's a wiring issue. I checked the remote wire and it had 12 volts, untill they cut out, then it had zero. I think the problem might be that the remote wire is shorting out somewhere under the seat, or the HU is messed up.
I sitll have to see if the 12 volts are comming out of the HU, and not getting to the amps when the amps cut out.
Thanks for responding. I thought about trying to see if my altenator might be the problem, but if it was, then I should be losing power to the whole vehicle, and I'm not. The wiring job under my seat is a mess going to my first amp (I can't believe I payed for that).
Someone told me that there's 3 wires that are connected to eachother when installing the HU? I think he said the remote wire, a 12v constant, and some other one. I'd check there, but I don't know how to install an HU.
cplkittle on 12/13/2003 22:19:34
DO NOT connect those 3 wires together.
the 12v power should be red and sometimes have an inline fuse, this should be connected to an aux power supply (comes on when you turn the key to aux or crank it.
The 12v constant will be yellow or orange and will also have an inline fuse, this should be connected to a constant power supply for clock and preprogram memory in the HU.
The remote wire (blue w/ white stripe) is power coming out of the radio to the remote connection to the amps. This tells your amps to turn on when the radio is turned on.
connecting power from the battery to the remote wire could seriously damage your HU.
if you are getting 12v from the remote at the HU, and not at the amps, there is a break in the wire. I would recommend either fixing that, or rerunning the remote wire only.
To further eliminate any other possibilities, disconnect the remote wire from both amps, and jump the power wire to the amp into the remote lead on the amp. all the remote connection on the amp needs is 12v to turn it on. This will turn your amps on constantly since the power to the amp is directly from the battery. If you have no problems when this is done, it is definitely your remote wire causing the problem. Don't forget to disconnect this when you are done, otherwise your amps will stay on all the time, even after the engine is off. I hope that was clear enough, sometimes I overexplain things.
alanjlamore on 12/13/2003 22:48:56
Thanks!! :)
This might sound dumb, but I thought about jumping a wire from the main power (going to the amp from the batterie), but I didn't know that the power from the battery was 12 volts also.
Should I disconnect the negative terminal from the battery before running a wire from the power to the remote, then, if this works, disconnect the neg terminal again to remove the wire?
I've always been scared to touch anything that has to do with power, especially since I now have a 1 farrad cap. I guess I don't understand electricity as well as I should.
Thanks again,
cplkittle on 12/13/2003 22:57:30
That would probably be wise. Caps will shock the crap out of you.
On second thought, since you have a cap, and I am not sure exactly how that would affect the remote input. I would just skip that altogether. Just rerun your origional remote wire, that is the safest thing to do. If that dosen't work, we'll go from there.
Jebus on 12/15/2003 16:39:14
I know this is pretty late, but I wanted to let you guys know about this site. I had to hook up some foglights recently, and this was the only site I found that had any useful info about car relays.
http://www.classictruckshop.com/clubs/earlyburbs/projects/how_to.htm
Go to "The Bosch Relay Explained" and to the link about fog/offroad lites. The site does not have much to do with car audio, but has more than you ever wanted to know about relays.
It gives a great, in-depth explanation of how a relay works, and some easy to follow schematics.
alanjlamore on 12/15/2003 17:24:34
OK, I just tested to see if the 12v were coming out of the HU, and it was. I then tested again to see if the 12v were getting to the amps, and it was there too!
At first, the multimeter showed OL when I tested at the amps, then it showed OL at the HU. When I checked again it had 12 volts at the HU, first amp and at the second amp, but there was still no power on the amps. I kept checking back and forth at the remote output from the HU and going into the amps and sure enough, the 12v were there the whole time without the amps kicking on.
On my way home the amps kicked on when I was stopped at a light, then stayed on for the whole 65 minute drive!!
I'm thinking it could be a bad grounding somewhere, or something in one of the amps is shorting and shorting the other amp since they're connected, but when there's enough current flowing near some of the wires some of the current bleeds just enough into the amps to keep them on?
I was so sure it was going to be the remote wire, but now I'm totaly lost. THINK
BTW, I also ohmed out the ground wire from the HU with a bolt on one of the seats and it showed a short like it should, so the HU is grounded properly.
ttocs on 12/16/2003 10:32:56
re run the remote wire. You can run a temporary one without tucking it under the carpet and see if that fixes it. It sounds like there is a loose connection somewhere. Turn the system on and start to wiggle all the connections until you recreate the problem.
alanjlamore on 12/16/2003 17:25:20
I tried moving wires around, but it didn't change anything. The amps cutting off and on will happen when the truck is not moving (never cuts on or off when I hit a bump), so I don't think it's a loose connection, but I'll check that again.
I also had a +12v at the amps (where the remote wire connects to the amps from the HU) with no power to the amps (after they cut out), so now I'm thinking it's not a remote wire problem.
Could it be that a ground wire is too thin, or the ground wire has a bad connection?
If it is grounded, but not very well, would I have these same symptoms?
Swez on 12/17/2003 11:16:55
Yes... you need a quality, paint, rust debris free connection to ground all amps and HU. It is best to use a floor pan ground on HU & amps. But in order to have an effective ground, the battery Neg must have a good grounding strap (proper gage) from engine and body grounds. See FAQ on properly grounded systems for more details.
Also, try disconnecting 1 amp and see if the one remaining will work properly. If not... you have a wiring issue to track down. The trouble could be in the following areas:
1. Poorly grounded system
2. Incorrect HU harness wiring taps
3. Intermittent HU REM voltage (run a jumper from B+ on amp to REM and see if that corrects the problem)
4. Perform voltage checks on B+/GND and REM/GND
If there is a poor ground here, the system will act flakey as noted. This means a solid ground connection from ENG/ALT/BAT to body. If you have a poor grounding strap, replace with a larger gage strap from body to engine. Now, the body is properly grounded.
If you have the HU harness wires connected to wrong power taps in fuse block (Ie: brakes, lights or other non-ACC/IGN lugs/wire) the HU will be affected and not operate properly when other circuits are engaged)
If you lose REM from HU to amps, they will not turn on or the amps will shut off. Most HU's can suppy limited current to REM only. This is a very low current source for DC voltage/current. Typical HU's can support 250-300mA of current draw. If the load (amps 1 & 2 REM) take more than that, the HU REM will be unstable, damaged or it will fail completely. You can do a quick test by removing the HU REM line from all amps and run a jumper from amp B+ (12 volt battery feed) to REM. If the amp(s) turn on now, your REM from HU is not working properly. A relay circuit or installing a manual REM feed will be needed or the REM line is not working properly from HU to AMPS.
NOTE: Most amps only need 15-30mA of current from REM to turn on. In most cases, 2-3 amplifiers can be run off a single REM. If you run additional REM circuits... may overload the HU and damage the REM circuit in HU.
Hope that helps... good luck and keep us up tgo date OK?
Swez
alanjlamore on 12/17/2003 17:32:41
Alright, I have some work to do now. :)
Thanks a lot!!
This forum is great, with a lot of knowledgable, patient, helpful people and I'll be donating as soon as I get some extra money.
The one thing that has always bothered me though is touching wires, even with the vehicle's negative battery terminal disconected. I keep thinking that I might produce a way for the electricity to find ground and I'd be like a big resistor. I had a bad experience once when touching a positive terminal of a battery of an old pontiac (when the neg was disconnected) and my thighs were touching the bumper. I got a tingling feeling in my legs and haev been afraid of batteries ever since.
Anyway, thanks again.
Swez on 12/17/2003 22:12:23
Caution and respect for shocks are a good thing when working with electricity. It's not the voltage that matters, but how much current we get into that can kill. A few amps of current and low voltage will sting or may cause a burn. But if there is enough current passed through the body via arms and hands.... it can do serious damage or kill if the shock resets heart rythem or stops it altogether. A few milliamps in the right place can kill. Not to scare you more... just be aware of your situation at all times.
A tip: Work in dry areas, avoid clutter and try to always keep one hand free of metal surfaces when working around electricity. If you do get a shock, it won't cross your chest to the heart. May sting, give you the "willies", but no real damage.
The ignition coil is the bugger you have to watch out for. It can produce 30-50,000 volts when engine is running. Not a lot of current in that circuit.... but it will shake you up a bit though.
CAPS can deliver a nasty whollup too. Always discharge a larger CAP before handling it. A 12 volt test light will do the job here. Just clip one side on to the HOT output and the other probe wire to ground... make sure the probe is well insulated with a rubber boot or plastic housing. When the light goes out, the charge is gone and safe to handle. Drain a cap slowly !!!
Good luck on the troubleshooting phase of your install. We're here to guide you.
Swez
PS The body normally has a high resistance value and will even handle 120 volt shocks pretty well if your hands, feet and clothing are dry. When we get wet or sweat, body resistance drops and we become better conductors, hense more current will flow. This is where ppl get injured... wet clothes or standing in a puddle of water without shoes can deliver a nasty shock.
ttocs on 12/17/2003 23:04:59
I like electrons....................
I have been shocked many times, some self induced when we were bored in tech school. I have never recieved anything more then a slight tingle after 7 yrs of installing. there is not a hole lot to worry about in a car unless you are licking a spark plug wire, but there is no reason to risk it. You will throw a few sparks from time to time, so be sure to have the proper saftey equipment.
alanjlamore on 12/18/2003 17:35:53
Thanks,
The main thing I'm worried about is touching my sony amp's ground wire when I try to re-wire the ground. I noticed that the ground wire going from the amp is 8 guage right up untill about four inches from the amp, then it has a smaller wire crimped onto it (for no reason that I can see), and that wire only has about 4 or 5 strands connected to the amp.
I plan on taking the neg terminal off of the truck battery, but I still think I could get shocked.
Should I disconnect the power going to the amp first, then the ground, and when putting it back should I connect the ground first then the power? Or would I be safe leaving the power connected as long as the neg is disconnected at the battery?
Hopefully this will be my last question about this problem.
Thanks again,
cplkittle on 12/18/2003 19:22:54
If you disconnect the negative on your battery, and the engine is off, you can not get shocked by any positive lead+chassis ground combination unless you have a cap. If you disconnect the cap as well, your vehicle has absolutely no charge + or - whatsoever.
1st, disconnect the negative terminal on the battery
2nd, disconnect the + lead to your amp from the cap (you can wrap it in tape if you wish)
now you are completely safe to do any wiring.
when you finish and have everything hooked back up, crank your car and let it idle for 5 minutes or so with the stereo off, to make sure your cap and battery are back up to normal before hitting the tunes.
Swez on 12/18/2003 21:59:03
Just an aside... removing the main power line fuse before you dig into amp rewiring is always wise. Then, discharge the cap and you'll be safe to work on the amp wires.
For an added margin of safety, pulling the Neg wire off the battery is never a bad idea also.
Swez
My problem is that my amps are cutting out when I drive slow, and kick back on when I drive over 55mph, or when I rev my engine a lot in neutral.
A friend of mine told me that it could have something to do with my remote turn-on being daisy chaned from one amp to the other, and that the truck (or cd player) isn't providing enough power threough the remote turn-on to keep the amps on. He also said that there's something I could buy at radio shack that will keep a constant power supply to the remote turn-on wire.
I called crutchfield and asked them about it and they said I should just have to get a capacitor, so I did, and I'm still having the same problem.
The amps stay on longer if I leave the radio off while driving the first few miles, or if I turn the subbs off with the cd player, but they'll still eventually turn off.
Does any one know what could be the problem?
I already know that the amps are not over heating since they'll shut off right away if I turn the radio on right away and then they'll kick on later.
Any help is greatly appreciated.
Thanks,
Alan LaMore
Replies (22)
ttocs on 11/26/2003 21:18:14
ok, don't call them anymore...
I had a simalar situation in a vehicle we worked on years ago. You didn't mention that there was a aftermarket HU? that was the case in this care. We tapped into what we thought was a switched ignition wire at the fusebox for the remote wire, it was for the cruise control infact. It would come on and off above and below a certain MPH. It cracked us up at the time as we thought the dude was nutz.....
I have to say that it has to do with the remote wire, but we need to test it to be sure. Do you have a testlight or voltmeter? You need to hook one up to the remote wire and simulate these conditions to see what the voltage is doing. Maybe take a freind with you to watch it while you drive, don't do anything unsafe/stupid.... If that stays at +12v we need to do the same with the constant.
You do not want to add anything to keep the remote turn on, on all the time. Your amps would not shut off, your battery would die...
alanjlamore on 11/26/2003 21:25:07
Yes, the HU is an alpine CDM-9801.
I can get a multimeter from where I work, and I will test to see if there's 12 volts comming out of the remote or not, but what do I do if there's not 12v comming out when it cuts off; and what should I do if there is?
I'm guessing that the voltage is dropping from the remote wire, but I'll test to make sure.
Thanks for the quick response,
Alan LaMore
alanjlamore on 11/26/2003 21:54:40
I just remembered that my friend was talking about installing a relay, but I don't know what kind to get, or how to install it.
Any suggestions?
cplkittle on 11/27/2003 09:46:49
What a relay does is take a small voltage to open a switch that allows higher voltage to pass through. It is like a flip switch except instead of you flipping it on, the remote wire from your stereo provides the voltage necessary to turn it on. Your friend is thinking that your remote wire is not providing the voltage necessary to tell the amps to come on.
If this is the problem, you can get one from radio shack. Tell them what you are doing, they should be able to help you. Make sure you get one rated higher than the combined total of the amps your amplifiers are pulling.
I have never seen this as a problem before, but I could be wrong. I am running a 600w amp and a 200w amp plus 2 neon lights with my remote wire. (when I say running the amps I mean as a remote, not a main source of power)
ttocs on 11/27/2003 20:34:27
I have seen it happen. If you want to test this theory, hook you remote wire going to your amps, to the +12v switched wire(red). It will provide enough current for the amps.
Relays are not all that hard, I can get you through it if we need to. I can always prewire one and ship it to you as well.
alanjlamore on 11/28/2003 08:51:53
If you could get me the kind of relay I need, and could tell me exactly where to wire it to, I'd be more than happy to pay you for the relay and a little extra for the install advice.
I have a paypal account and would prefer to do it that way if you have one too.
Let me know if you'd be able to or not.
BTW, I don't know if you need this info or not, but my sony amp is a 75w rms X 4 channels, and my mono sub amp puts out 500w rms when wired for 2 ohms. They're in a 2000 Dodge Dakota.
Thanks,
Alan LaMore
cinci23 on 12/4/2003 13:13:00
Hey Alan. What kind of wiring kit do you have. i have a sony amp and at first I was thinking overheating because mine did that. What it sounds like though is your amp is definately not getting enough power. This can be attributed to your wiring kit. I dont know anything about a remote relay though. Just that when you rev your car you get more power, that is saying that your are not getting enough initially. So I am wondering about your wiring kit. Later. Nick
alanjlamore on 12/13/2003 22:08:26
The wiring kit I have uses a 4 guage wire going from the battery to a distribution block, and has two 8 guage wires going to each amp. The wires are more than thick enough for the power.
I started realizing that the amps will kick back on when I hit the brake, or when the doors lock (happens automatically when I reach 15 mph).
Sometimes they kick on while I'm stopped at a light, and other times they won't. The amps are not overheating, because it happens right when I start the truck, and sometimes they stay on for a long time.
I think it's a wiring issue. I checked the remote wire and it had 12 volts, untill they cut out, then it had zero. I think the problem might be that the remote wire is shorting out somewhere under the seat, or the HU is messed up.
I sitll have to see if the 12 volts are comming out of the HU, and not getting to the amps when the amps cut out.
Thanks for responding. I thought about trying to see if my altenator might be the problem, but if it was, then I should be losing power to the whole vehicle, and I'm not. The wiring job under my seat is a mess going to my first amp (I can't believe I payed for that).
Someone told me that there's 3 wires that are connected to eachother when installing the HU? I think he said the remote wire, a 12v constant, and some other one. I'd check there, but I don't know how to install an HU.
cplkittle on 12/13/2003 22:19:34
DO NOT connect those 3 wires together.
the 12v power should be red and sometimes have an inline fuse, this should be connected to an aux power supply (comes on when you turn the key to aux or crank it.
The 12v constant will be yellow or orange and will also have an inline fuse, this should be connected to a constant power supply for clock and preprogram memory in the HU.
The remote wire (blue w/ white stripe) is power coming out of the radio to the remote connection to the amps. This tells your amps to turn on when the radio is turned on.
connecting power from the battery to the remote wire could seriously damage your HU.
if you are getting 12v from the remote at the HU, and not at the amps, there is a break in the wire. I would recommend either fixing that, or rerunning the remote wire only.
To further eliminate any other possibilities, disconnect the remote wire from both amps, and jump the power wire to the amp into the remote lead on the amp. all the remote connection on the amp needs is 12v to turn it on. This will turn your amps on constantly since the power to the amp is directly from the battery. If you have no problems when this is done, it is definitely your remote wire causing the problem. Don't forget to disconnect this when you are done, otherwise your amps will stay on all the time, even after the engine is off. I hope that was clear enough, sometimes I overexplain things.
alanjlamore on 12/13/2003 22:48:56
Thanks!! :)
This might sound dumb, but I thought about jumping a wire from the main power (going to the amp from the batterie), but I didn't know that the power from the battery was 12 volts also.
Should I disconnect the negative terminal from the battery before running a wire from the power to the remote, then, if this works, disconnect the neg terminal again to remove the wire?
I've always been scared to touch anything that has to do with power, especially since I now have a 1 farrad cap. I guess I don't understand electricity as well as I should.
Thanks again,
cplkittle on 12/13/2003 22:57:30
That would probably be wise. Caps will shock the crap out of you.
On second thought, since you have a cap, and I am not sure exactly how that would affect the remote input. I would just skip that altogether. Just rerun your origional remote wire, that is the safest thing to do. If that dosen't work, we'll go from there.
Jebus on 12/15/2003 16:39:14
I know this is pretty late, but I wanted to let you guys know about this site. I had to hook up some foglights recently, and this was the only site I found that had any useful info about car relays.
http://www.classictruckshop.com/clubs/earlyburbs/projects/how_to.htm
Go to "The Bosch Relay Explained" and to the link about fog/offroad lites. The site does not have much to do with car audio, but has more than you ever wanted to know about relays.
It gives a great, in-depth explanation of how a relay works, and some easy to follow schematics.
alanjlamore on 12/15/2003 17:24:34
OK, I just tested to see if the 12v were coming out of the HU, and it was. I then tested again to see if the 12v were getting to the amps, and it was there too!
At first, the multimeter showed OL when I tested at the amps, then it showed OL at the HU. When I checked again it had 12 volts at the HU, first amp and at the second amp, but there was still no power on the amps. I kept checking back and forth at the remote output from the HU and going into the amps and sure enough, the 12v were there the whole time without the amps kicking on.
On my way home the amps kicked on when I was stopped at a light, then stayed on for the whole 65 minute drive!!
I'm thinking it could be a bad grounding somewhere, or something in one of the amps is shorting and shorting the other amp since they're connected, but when there's enough current flowing near some of the wires some of the current bleeds just enough into the amps to keep them on?
I was so sure it was going to be the remote wire, but now I'm totaly lost. THINK
BTW, I also ohmed out the ground wire from the HU with a bolt on one of the seats and it showed a short like it should, so the HU is grounded properly.
ttocs on 12/16/2003 10:32:56
re run the remote wire. You can run a temporary one without tucking it under the carpet and see if that fixes it. It sounds like there is a loose connection somewhere. Turn the system on and start to wiggle all the connections until you recreate the problem.
alanjlamore on 12/16/2003 17:25:20
I tried moving wires around, but it didn't change anything. The amps cutting off and on will happen when the truck is not moving (never cuts on or off when I hit a bump), so I don't think it's a loose connection, but I'll check that again.
I also had a +12v at the amps (where the remote wire connects to the amps from the HU) with no power to the amps (after they cut out), so now I'm thinking it's not a remote wire problem.
Could it be that a ground wire is too thin, or the ground wire has a bad connection?
If it is grounded, but not very well, would I have these same symptoms?
Swez on 12/17/2003 11:16:55
Yes... you need a quality, paint, rust debris free connection to ground all amps and HU. It is best to use a floor pan ground on HU & amps. But in order to have an effective ground, the battery Neg must have a good grounding strap (proper gage) from engine and body grounds. See FAQ on properly grounded systems for more details.
Also, try disconnecting 1 amp and see if the one remaining will work properly. If not... you have a wiring issue to track down. The trouble could be in the following areas:
1. Poorly grounded system
2. Incorrect HU harness wiring taps
3. Intermittent HU REM voltage (run a jumper from B+ on amp to REM and see if that corrects the problem)
4. Perform voltage checks on B+/GND and REM/GND
If there is a poor ground here, the system will act flakey as noted. This means a solid ground connection from ENG/ALT/BAT to body. If you have a poor grounding strap, replace with a larger gage strap from body to engine. Now, the body is properly grounded.
If you have the HU harness wires connected to wrong power taps in fuse block (Ie: brakes, lights or other non-ACC/IGN lugs/wire) the HU will be affected and not operate properly when other circuits are engaged)
If you lose REM from HU to amps, they will not turn on or the amps will shut off. Most HU's can suppy limited current to REM only. This is a very low current source for DC voltage/current. Typical HU's can support 250-300mA of current draw. If the load (amps 1 & 2 REM) take more than that, the HU REM will be unstable, damaged or it will fail completely. You can do a quick test by removing the HU REM line from all amps and run a jumper from amp B+ (12 volt battery feed) to REM. If the amp(s) turn on now, your REM from HU is not working properly. A relay circuit or installing a manual REM feed will be needed or the REM line is not working properly from HU to AMPS.
NOTE: Most amps only need 15-30mA of current from REM to turn on. In most cases, 2-3 amplifiers can be run off a single REM. If you run additional REM circuits... may overload the HU and damage the REM circuit in HU.
Hope that helps... good luck and keep us up tgo date OK?
Swez
alanjlamore on 12/17/2003 17:32:41
Alright, I have some work to do now. :)
Thanks a lot!!
This forum is great, with a lot of knowledgable, patient, helpful people and I'll be donating as soon as I get some extra money.
The one thing that has always bothered me though is touching wires, even with the vehicle's negative battery terminal disconected. I keep thinking that I might produce a way for the electricity to find ground and I'd be like a big resistor. I had a bad experience once when touching a positive terminal of a battery of an old pontiac (when the neg was disconnected) and my thighs were touching the bumper. I got a tingling feeling in my legs and haev been afraid of batteries ever since.
Anyway, thanks again.
Swez on 12/17/2003 22:12:23
Caution and respect for shocks are a good thing when working with electricity. It's not the voltage that matters, but how much current we get into that can kill. A few amps of current and low voltage will sting or may cause a burn. But if there is enough current passed through the body via arms and hands.... it can do serious damage or kill if the shock resets heart rythem or stops it altogether. A few milliamps in the right place can kill. Not to scare you more... just be aware of your situation at all times.
A tip: Work in dry areas, avoid clutter and try to always keep one hand free of metal surfaces when working around electricity. If you do get a shock, it won't cross your chest to the heart. May sting, give you the "willies", but no real damage.
The ignition coil is the bugger you have to watch out for. It can produce 30-50,000 volts when engine is running. Not a lot of current in that circuit.... but it will shake you up a bit though.
CAPS can deliver a nasty whollup too. Always discharge a larger CAP before handling it. A 12 volt test light will do the job here. Just clip one side on to the HOT output and the other probe wire to ground... make sure the probe is well insulated with a rubber boot or plastic housing. When the light goes out, the charge is gone and safe to handle. Drain a cap slowly !!!
Good luck on the troubleshooting phase of your install. We're here to guide you.
Swez
PS The body normally has a high resistance value and will even handle 120 volt shocks pretty well if your hands, feet and clothing are dry. When we get wet or sweat, body resistance drops and we become better conductors, hense more current will flow. This is where ppl get injured... wet clothes or standing in a puddle of water without shoes can deliver a nasty shock.
ttocs on 12/17/2003 23:04:59
I like electrons....................
I have been shocked many times, some self induced when we were bored in tech school. I have never recieved anything more then a slight tingle after 7 yrs of installing. there is not a hole lot to worry about in a car unless you are licking a spark plug wire, but there is no reason to risk it. You will throw a few sparks from time to time, so be sure to have the proper saftey equipment.
alanjlamore on 12/18/2003 17:35:53
Thanks,
The main thing I'm worried about is touching my sony amp's ground wire when I try to re-wire the ground. I noticed that the ground wire going from the amp is 8 guage right up untill about four inches from the amp, then it has a smaller wire crimped onto it (for no reason that I can see), and that wire only has about 4 or 5 strands connected to the amp.
I plan on taking the neg terminal off of the truck battery, but I still think I could get shocked.
Should I disconnect the power going to the amp first, then the ground, and when putting it back should I connect the ground first then the power? Or would I be safe leaving the power connected as long as the neg is disconnected at the battery?
Hopefully this will be my last question about this problem.
Thanks again,
cplkittle on 12/18/2003 19:22:54
If you disconnect the negative on your battery, and the engine is off, you can not get shocked by any positive lead+chassis ground combination unless you have a cap. If you disconnect the cap as well, your vehicle has absolutely no charge + or - whatsoever.
1st, disconnect the negative terminal on the battery
2nd, disconnect the + lead to your amp from the cap (you can wrap it in tape if you wish)
now you are completely safe to do any wiring.
when you finish and have everything hooked back up, crank your car and let it idle for 5 minutes or so with the stereo off, to make sure your cap and battery are back up to normal before hitting the tunes.
Swez on 12/18/2003 21:59:03
Just an aside... removing the main power line fuse before you dig into amp rewiring is always wise. Then, discharge the cap and you'll be safe to work on the amp wires.
For an added margin of safety, pulling the Neg wire off the battery is never a bad idea also.
Swez
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