Hi guys, I recently swapped out the tape deck in my 89 Charade with a Kenwood CD/MP3/Tuner.
I'm still using the stock speakers (4x 6") and no subwoofer, so I assumed I didn't need an amp or anything.
Wired up the speakers, and ran twin-core 5mm TPS cable directly to the battery for power.
Everything works great with the engine off, but when the car is running at low-med revs, there's a huge amount of crackling that comes through, and it's driving me insane lol.
Any ideas what the problem could be? I'd appreciate *any* sort of advice or suggestion at this stage.
(Hoping I'm not gonna cop too much flak for such a basic p*ssweak system, but I'm a complete novice, and since I just wanted to be able to play CDs/MP3s, and spending any sort of serious money on a $1000 car just doesn't seem smart to me.)
Replies (9)
swez on 02/17/2009 20:07:36
Welcome to CK!
Am not familiar with this vehicle and since it is older, you may have to check the speakers to see if they used a common body ground for the negative speaker terminals.
If yes, in order for the system to work properly, you'll need to run fresh paired speaker lines for the HU/Tuner speaker outputs to each speaker used. Aftermarket players have their own grounding system and will not tolerate body grounded speakers.
Tech Tip: A cheap and simple "Continuity Test Light" would work. If you have an ohmeter handy, even better.
Also, when you installed this Kenwood player, where did you ground the black wire?
a. To the dash wiring harness ground?
b. To a bare metal panel in the dash?
Comments,
Swez
Dragunov-21 on 02/17/2009 23:56:06
Thanks Swez.
How do I check the speakers? There is a paired speaker cable running from each speaker - I assume there would only be one if it was grounded to the body of the car? (I have a multimeter).
As for grounding the stereo, I ran the negative power lead straight to the negative terminal of the battery.
swez on 02/18/2009 03:35:41
To test your speaker grounds, follow these steps:
1. Set the meter to ohms scale and 1-10 ohm scale (Be sure it zero's out if the older style analog type meter w/ swinging needle indicator)
2. Remove the Negative battery post connector
3. Measure resistance from each speaker, (+/-) terminal to body ground (Bare metal)
3a. If the meter reads infinite resistance, (No discernable value) on either speaker terminal, that's good
3b. If meter reads well below 5 ohms, it's likely you have a common ground wire for the Neg and new speaker rewiring is needed
Also, that dual core, 5mm cable mentioned, is that a coaxial type cable used for microphones and guitar cables? (Twin leads and a shielded ground outer jacket?)
If yes, that may be your next fix. Do you have specs or a link to that specific cable?
Say more,
Swez
PS Which version Charade is this? After looking it up, I noted a compact sedan and a high performance version from Daihatsu. (Mostly in the UK?) Small format sports car is Turbo charged, GTti or a small, gas-sipping sedan/hatchback, the CX series?
Dragunov-21 on 02/19/2009 00:48:39
The cable I'm using from the battery terminals to the +/- power terminals of the stereo is basically building wire, similar to this (2.5mm not 5mm, my mistake):
http://www.generalcable.com.au/Australia/Products/Energy/Building_Conduit_Wires/4.1.2.1.8.pdf
I didn't think I needed any particular type of cable for power, could that be my problem?
The charade is a standard one litre hatchback, see the G100 series below (mine is exactly the same as the 1989 Daihatsu Charade CES (North American)):
http://en.wikipedia.org/wiki/Daihatsu_Charade
I'll check the speakers tonight.
swez on 02/19/2009 17:01:52
I think that the wire used is part of the problem. Also routing of this wire may be adding to your noise issues.
See, paired wires like this act like an RF antenna. When paired like this, they pick up engine noise that is tolerable for added lighting or non-audio devices. But for audio gear feeds, you get the voltage plus any noise the engine emits from the ALT, spark plugs and other electronic circuits. These are difficult to filter out.
In your case, a single conductor may help and ground the HU to bare metal in the dash. Since there is no RF antenna effect this way, the noise is minimal if not eliminated completely.
Try that and see if you get the desired results. You can use the wire in there now, but use both off the Pos battery and at the HU end, disconnect the ground and tape it off. Ground the HU to bare metal in the dash, floorpan or firewall. In most cases, your noise should go away.
Good luck,
Swez
Dragunov-21 on 02/23/2009 17:00:14
So just after I posted my last message, I had a thought from what you said - and I measured resistance between the neg terminal and the chassis of the car: ~5 ohms.
Apparently I'm gonna have to check the strap, but in the mean time I've just connected the stereo negative to the chassis of the car (like you just said lol), and it works a treat!
Cheers Swez, you're the man =D
swez on 02/23/2009 19:14:25
Whew... that's good to hear as this is one of the most difficult issues to resolve. (Horrible Ground Loops)
A 5 ohm drop screams a bad ground connection either at the battery post to chassis or a secondary ground strap from the engine block to chassis. (Think rust and corrosion as the main culprits or a bad grounding strap)
Nice detective work,
Swez
Dragunov-21 on 02/24/2009 18:58:26
Never even thought to check until you mentioned issues with common grounding of the speakers, thanks again =D
swez on 02/24/2009 20:01:09
Sure, and based on your last report, speakers gounded to chassis are not that common anymore.
It's worth a quick test with your ohmeter, but it seems that a severe "ground loop" was most of the primary noise problem. (Wiring the HU direct to the battery)
Common ground speakers were the norm is US made vehicles into the early-80's. That may not be the case with your vehicle, but a simple check is all that is needed to rule it out.
Check it out, just to be sure,
Swez
I'm still using the stock speakers (4x 6") and no subwoofer, so I assumed I didn't need an amp or anything.
Wired up the speakers, and ran twin-core 5mm TPS cable directly to the battery for power.
Everything works great with the engine off, but when the car is running at low-med revs, there's a huge amount of crackling that comes through, and it's driving me insane lol.
Any ideas what the problem could be? I'd appreciate *any* sort of advice or suggestion at this stage.
(Hoping I'm not gonna cop too much flak for such a basic p*ssweak system, but I'm a complete novice, and since I just wanted to be able to play CDs/MP3s, and spending any sort of serious money on a $1000 car just doesn't seem smart to me.)
Replies (9)
swez on 02/17/2009 20:07:36
Welcome to CK!
Am not familiar with this vehicle and since it is older, you may have to check the speakers to see if they used a common body ground for the negative speaker terminals.
If yes, in order for the system to work properly, you'll need to run fresh paired speaker lines for the HU/Tuner speaker outputs to each speaker used. Aftermarket players have their own grounding system and will not tolerate body grounded speakers.
Tech Tip: A cheap and simple "Continuity Test Light" would work. If you have an ohmeter handy, even better.
Also, when you installed this Kenwood player, where did you ground the black wire?
a. To the dash wiring harness ground?
b. To a bare metal panel in the dash?
Comments,
Swez
Dragunov-21 on 02/17/2009 23:56:06
Thanks Swez.
How do I check the speakers? There is a paired speaker cable running from each speaker - I assume there would only be one if it was grounded to the body of the car? (I have a multimeter).
As for grounding the stereo, I ran the negative power lead straight to the negative terminal of the battery.
swez on 02/18/2009 03:35:41
To test your speaker grounds, follow these steps:
1. Set the meter to ohms scale and 1-10 ohm scale (Be sure it zero's out if the older style analog type meter w/ swinging needle indicator)
2. Remove the Negative battery post connector
3. Measure resistance from each speaker, (+/-) terminal to body ground (Bare metal)
3a. If the meter reads infinite resistance, (No discernable value) on either speaker terminal, that's good
3b. If meter reads well below 5 ohms, it's likely you have a common ground wire for the Neg and new speaker rewiring is needed
Also, that dual core, 5mm cable mentioned, is that a coaxial type cable used for microphones and guitar cables? (Twin leads and a shielded ground outer jacket?)
If yes, that may be your next fix. Do you have specs or a link to that specific cable?
Say more,
Swez
PS Which version Charade is this? After looking it up, I noted a compact sedan and a high performance version from Daihatsu. (Mostly in the UK?) Small format sports car is Turbo charged, GTti or a small, gas-sipping sedan/hatchback, the CX series?
Dragunov-21 on 02/19/2009 00:48:39
The cable I'm using from the battery terminals to the +/- power terminals of the stereo is basically building wire, similar to this (2.5mm not 5mm, my mistake):
http://www.generalcable.com.au/Australia/Products/Energy/Building_Conduit_Wires/4.1.2.1.8.pdf
I didn't think I needed any particular type of cable for power, could that be my problem?
The charade is a standard one litre hatchback, see the G100 series below (mine is exactly the same as the 1989 Daihatsu Charade CES (North American)):
http://en.wikipedia.org/wiki/Daihatsu_Charade
I'll check the speakers tonight.
swez on 02/19/2009 17:01:52
I think that the wire used is part of the problem. Also routing of this wire may be adding to your noise issues.
See, paired wires like this act like an RF antenna. When paired like this, they pick up engine noise that is tolerable for added lighting or non-audio devices. But for audio gear feeds, you get the voltage plus any noise the engine emits from the ALT, spark plugs and other electronic circuits. These are difficult to filter out.
In your case, a single conductor may help and ground the HU to bare metal in the dash. Since there is no RF antenna effect this way, the noise is minimal if not eliminated completely.
Try that and see if you get the desired results. You can use the wire in there now, but use both off the Pos battery and at the HU end, disconnect the ground and tape it off. Ground the HU to bare metal in the dash, floorpan or firewall. In most cases, your noise should go away.
Good luck,
Swez
Dragunov-21 on 02/23/2009 17:00:14
So just after I posted my last message, I had a thought from what you said - and I measured resistance between the neg terminal and the chassis of the car: ~5 ohms.
Apparently I'm gonna have to check the strap, but in the mean time I've just connected the stereo negative to the chassis of the car (like you just said lol), and it works a treat!
Cheers Swez, you're the man =D
swez on 02/23/2009 19:14:25
Whew... that's good to hear as this is one of the most difficult issues to resolve. (Horrible Ground Loops)
A 5 ohm drop screams a bad ground connection either at the battery post to chassis or a secondary ground strap from the engine block to chassis. (Think rust and corrosion as the main culprits or a bad grounding strap)
Nice detective work,
Swez
Dragunov-21 on 02/24/2009 18:58:26
Never even thought to check until you mentioned issues with common grounding of the speakers, thanks again =D
swez on 02/24/2009 20:01:09
Sure, and based on your last report, speakers gounded to chassis are not that common anymore.
It's worth a quick test with your ohmeter, but it seems that a severe "ground loop" was most of the primary noise problem. (Wiring the HU direct to the battery)
Common ground speakers were the norm is US made vehicles into the early-80's. That may not be the case with your vehicle, but a simple check is all that is needed to rule it out.
Check it out, just to be sure,
Swez
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