alright i was helping a freind out but before i start rippnig his whole interior apart ill double check here for comfirmation of where the problem could be....im pretty sure the speaker leads are shorting to ground or to themselves....because i had a similar problem a week or two ago...now his speakers sometimes work and sometimes dont when the deck is on, but the weird part about it is when you turn the deck off the speaker i assume is shorting is outputing a whining noise...i forget the proper teriminology for the whine but it goes w/ the revs of the car etc and gets louder w/ greater elec strain and it happens only sometimes, when its not whining i can turn the deck on and get sound for a little while then it shorts and all the popping noise and what not...now he has a 4 channel amp running these speakers and what not but i assume none of that matters, i checked the obvious shorting areas at the amp itself, but he's running rca's from the deck to his amp and then speaker wire to the speakers...so any help before i tear his interior apart searchign for the short...PROUD
Replies (4)
Swez on 06/29/2003 13:00:44
If you have an ohm meter, you can check the DC resistance between the speaker leads with the speaker wires removed from the amp.
I f you find one well under 3.2 ohms or so, this is the one to look at first. If the resistance reads "0"... dead short. if the meter does not read any value, the circuit is open.
With the HU (deck) off, you can hear alternator whine in the same speaker? Check the amp and see if it is off, whe the HU is turned off as well. If the amp is still on, it sounds like the amp grounds are not as good as they need to be... bare metal to floor pan etc.
Finally, check the amp gain settings on the 4 channel amp. They should be set close to mid-point or ~1.5-2.0 volts area. If amp gains are set too high (near 1.0 volts) the amp can pick up noise this way as well.
Good luck!
Swez
drumking15 on 06/29/2003 13:37:52
alright, ive run into some other problems which i have never inccured before, i tracked down the short in the wire between his door and his speakers there was a crimp in the wires and it was shorting to ground...now my new problem is so bizarre....i turn on the HU and i get sound that is distorted w/ a hissing noise almost like a weak radio signal sound...but its from radio and cd and the power on the amps is jumpy...by this i mean the leds on the amp itself are fluctating...they almost flash so weird ive never experience this before, im gonna go pick up my freinds meter but this is weird...any help on where to look etc...thanks
drumking15 on 06/29/2003 14:18:00
alright, this is so weird....i went and got a meter from my freind tested all the speaker leads first 3.6 across the board except for one where he blew a speaker and is waiting on a replacement....then i checked my power leads 12.6 across the board to...so then i turned the HU on and got reg. sound like normal and double checked the remote turn on voltage...i forget what it was something like 6volts but it was rather low...so i have changed absolutely nothing since about an hour ago and now it works...i swear car audio will be my biggest nightmare....electronics suck!!! mechnically things rule! neways hopefully it will work when i put everythign back together...but have any of you ever seen an amp just flicker like that? i was soo freeked out by it
Swez on 06/29/2003 18:13:13
That's why we get paid the big money as ET's & EE's... this is not an easy nut to crack!
Sounds like the HU REMote feeder is a bit low. How many amps are using that line as a turn on signal?
This amp you are having trouble with... what kind is it and how old do you think it might be? I ask as if it is new, the amp may be defective or have improper grounds.
If the amp is several years old, may have a flakey circuit board connection here and is intermittent. Things like weather (humidity and temperature) will definitely have an effect on a iffy board.
If you are brave and have a few basic electronics tools, can open the casing and have a look around at the circuit board(s) inside. May have a few bad solder joints is all. A good cleaning or the board(s) with IPA (rubbing alcohol) will help uncover any anomolies present on the board. Can walk you through the process if you like.
Finally, have you checked the power at the battery terminals with the engine running and then off ? When running should get a solid 13.5 volts or so here. When engine is off, battery power should be 12.x volts. If you see any major deviation from these numbers, your friend may have a bad battery or alternator problems pending.
Again, make sure all grounds are tight and free of rust and corrosion on all the major connections between ALT/BAT and BAT/GND... all the way back to amp(s) and HU.
Good luck... I feel for ya!
Swez
Replies (4)
Swez on 06/29/2003 13:00:44
If you have an ohm meter, you can check the DC resistance between the speaker leads with the speaker wires removed from the amp.
I f you find one well under 3.2 ohms or so, this is the one to look at first. If the resistance reads "0"... dead short. if the meter does not read any value, the circuit is open.
With the HU (deck) off, you can hear alternator whine in the same speaker? Check the amp and see if it is off, whe the HU is turned off as well. If the amp is still on, it sounds like the amp grounds are not as good as they need to be... bare metal to floor pan etc.
Finally, check the amp gain settings on the 4 channel amp. They should be set close to mid-point or ~1.5-2.0 volts area. If amp gains are set too high (near 1.0 volts) the amp can pick up noise this way as well.
Good luck!
Swez
drumking15 on 06/29/2003 13:37:52
alright, ive run into some other problems which i have never inccured before, i tracked down the short in the wire between his door and his speakers there was a crimp in the wires and it was shorting to ground...now my new problem is so bizarre....i turn on the HU and i get sound that is distorted w/ a hissing noise almost like a weak radio signal sound...but its from radio and cd and the power on the amps is jumpy...by this i mean the leds on the amp itself are fluctating...they almost flash so weird ive never experience this before, im gonna go pick up my freinds meter but this is weird...any help on where to look etc...thanks
drumking15 on 06/29/2003 14:18:00
alright, this is so weird....i went and got a meter from my freind tested all the speaker leads first 3.6 across the board except for one where he blew a speaker and is waiting on a replacement....then i checked my power leads 12.6 across the board to...so then i turned the HU on and got reg. sound like normal and double checked the remote turn on voltage...i forget what it was something like 6volts but it was rather low...so i have changed absolutely nothing since about an hour ago and now it works...i swear car audio will be my biggest nightmare....electronics suck!!! mechnically things rule! neways hopefully it will work when i put everythign back together...but have any of you ever seen an amp just flicker like that? i was soo freeked out by it
Swez on 06/29/2003 18:13:13
That's why we get paid the big money as ET's & EE's... this is not an easy nut to crack!
Sounds like the HU REMote feeder is a bit low. How many amps are using that line as a turn on signal?
This amp you are having trouble with... what kind is it and how old do you think it might be? I ask as if it is new, the amp may be defective or have improper grounds.
If the amp is several years old, may have a flakey circuit board connection here and is intermittent. Things like weather (humidity and temperature) will definitely have an effect on a iffy board.
If you are brave and have a few basic electronics tools, can open the casing and have a look around at the circuit board(s) inside. May have a few bad solder joints is all. A good cleaning or the board(s) with IPA (rubbing alcohol) will help uncover any anomolies present on the board. Can walk you through the process if you like.
Finally, have you checked the power at the battery terminals with the engine running and then off ? When running should get a solid 13.5 volts or so here. When engine is off, battery power should be 12.x volts. If you see any major deviation from these numbers, your friend may have a bad battery or alternator problems pending.
Again, make sure all grounds are tight and free of rust and corrosion on all the major connections between ALT/BAT and BAT/GND... all the way back to amp(s) and HU.
Good luck... I feel for ya!
Swez
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