Stereo Stopped Working

[TaffyTim 6]

My car has been used as a weekend toy for a while now but due to selling my Honda its now my main ride again.

 

One of the items in my 205 that has always seemed to work is the stereo, a Sony minidisc player, so ive never really fussed with it. As its not been updated in a while and as its 6x9s are pretty much dead i thought i'd get some replacements off gumtree.

 

I picked the bits up today and I though I'd check out the old ones to see how good the improvement was going to be. Typically here was nothing, the head unit was dead, not powering up at all!! I dont know how long its been like this as i dont have the system on much but it was working the last time i needed it to, maybe the end of last year.

 

I have had water ingress problems in the car but not anywhere near the head unit. Its been coming in through the passenger foot well sound deadening and it was coming in to the boot where the cd changer was. The cd changer has since been taken out.

 

Where should i start to look for my issue, could removing the disc changer had any affect? Would this have been acting as an earth?

 

A while ago i removed the amp but the old head unit has been working since then so i'm sure i can rule that out.

 

I have connected the new JVC unit today keeping my fingers crossed but this has no power either. When connecting it i disconnected the 12v remote and the 12v memory wires that were badly tapped into the head unit wiring. I cant see this having any bad affect as the old head unit was suffering no power before i did this. Correct me if im wrong.

 

This may be an issue for later but on the new units wiring loom all seems well on the speaker connecting block but on the power block it doesn't have the 25C wire going from the block to the back of headunit. So coming from the car loom this wire is there numbered 25C, its there on the orange block to the double split block labelled as illumination and then it will end as the connecting block doesnt have a wire to take it to the head unit.

 

Help will be much appreciated

 

 

 

 

 

 

[TaffyTim 6]

I've tested the wiring with a multimeter today.

 

I've pot it on V direct and put black probe onto bodywork and touched the pins going into the back of both head units when connected up. Results were the same on both units.

 

12v+ IGN:

no reading when key off, 11.9v when key on

 

Key then left on:

 

12v MEMORY:

12.0v

 

EARTH:

11.8v

 

ANTENNA REMOTE

11.8v

 

ILLUMINATION

No wire on either old or new headunit

 

All speakers wires 11.8v

 

Are these the figures that you'd expect or is something wrong?

[Anthony 1,003]

There shouldn't be 12v on the earth wire - it should be 0v as it is, in effect, exactly the same as the earth point on shell you're checking against (or certainly should be!)

 

The speaker wires shouldn't be constant 12v either I wouldn't have thought, although I've never checked them with a multimeter.

 

Are you sure you're checking correctly, as everything being 12v sounds very odd? You should only really have two 12v feeds from the 205 loom - a 12v constant for the stereo memory, and a switched 12v to power it up. I can't rememeber the numbers/colours off the top of my head, but they'll be two of the thicker wires, with the remaining one being the earth.

[TaffyTim 6]

I just checked again and yes the earth is getting just under 12v!!

 

Could this mean that I have a wire shorting on the shell somewhere?

[TaffyTim 6]

. .. thinking about my electrical gremlins yesterday the oil temp gauge wss showing a full reading but the warning light was not on so i ignored that (water temp was normal).

 

Also the starter was playing up, Ive got a separately wired switch which always works and twice it was temperamental!! Could this be shorting out?

 

When just checking the earth at the plug, not connected to the head unit there is no volts

Edited March 4, 2013 by TaffyTim

[TaffyTim 6]

Checking into this further it looks like an earthing issue.

 

If i plug the stereo in, then earth the whole unit to the bodywork then it sprins into life.

 

I then switched the multimeter to ohms and hit the bodywork with black probe and hit the earth pin on the wiring block and the reading doesnt change.

 

I dont know where to start tracing this back. Maybe i'll just earth the unit to the body by itself?

[Anthony 1,003]

Poke a temporary earth cable into the back of the stereo plug and connect it to a good, clean earth - does it then work?

[TaffyTim 6]

yep it works now by doing the above, thanks Anthony.

 

Wire screwed onto the back of the head unit then ive run it to one of the bolts by the gearstick with a bullet connector in the line to help if the stereo is removed at a later time.

 

I've checked and tightened the earths in the engine bay but it had no affect on getting the head unit working. I take it this is where the stereo gets its earth from.

 

Im not sure if I'll bother trying any harder to find the problem earth unless anyone has any ideas of typical places where this breaks?

[Anthony 1,003]

The other end of the stereo earth is, from memory, on the earth blocks on the steering column.

 

Certainly on my old '89 205 it was a single green/yellow wire with a spade on the end that earthed to the left hand side (you may or may not have earth blocks on both sides)

[TaffyTim 6]

ta muchly, i'll have a look there tomorrow.