GQ Replacement Stereo

[simongnz]

Hi, I have a 1990 GQ Safari with a double-decker Japanese stereo that doesn't work. I want to replace it with something a bit more modern and operational.

Last night I pulled the old unit out and had a bit of a look at the wiring and it appears that it's earthed via the antenna through some weird Nissan two pin plug. A new head unit bought in NZ won't be earthed in this way. I can get the wiring loom adapters from Repco but as the factory wiring loom doesn't have an earth wire on offer, I guess I'll need to splice something in myself.

Does anyone have any experience replacing the head unit in this type of vehicle they could share to help me along the way? I'm hoping to get it all sorted this weekend and would rather learn from others' experience first if possible.

Cheers,

Simon

[YNOT]

I have done it using the adaptor wiring harnesses and from memory I had to run my own power and earth wires.
Be careful of your voltages, most if not all Safari's ran a 24 volt system so installing a 12 volt radio will require a voltage converter.

Tony

[simongnz]

I have done it using the adaptor wiring harnesses and from memory I had to run my own power and earth wires.
Be careful of your voltages, most if not all Safari's ran a 24 volt system so installing a 12 volt radio will require a voltage converter.

Tony

Cheers. Mine's a 24V system but the feed going to the factory stereo is 12V. I've got an even-charger fitted so the tow-plug can pull 12V so I guess I could wire it up to that if necessary.

[timbar]

or u can check the mounting bracket is earthed and put a loop connector on the earth wire and attach it to the mounting bracket

[simongnz]

or u can check the mounting bracket is earthed and put a loop connector on the earth wire and attach it to the mounting bracket

Yes, that's what I was thinking would do the trick.

[simongnz]

Righto - I've got the stereo all hooked up and working, BUT, it seems to not have quite enough current. I'm guessing this because of:
- When I put a CD in the head unit it turns on and off repeatedly
- When I plug an ipod into the AUX it plays fine unless I turn the volume up too high at which point it turns of and on until I turn it down
- Radio is same as AUX although can be a bit louder

Can anyone give me some pointers on how to wire a positive lead directly from the battery? The GQ is a 24V system but I have an even charger fitted for the towing electrics. Does this mean I can run a (fused) connection straight off a battery terminal or do I need to do something else?

Any help gratefully accepted.

[Silver]

what does the radio manual say are acceptable input voltages? Unless it includes 24 and a bit more, a fuse won't solve your problem I think if you connect to the battery direct.

Is there a Jaycar in your part of the world? they will have some sort of step down device if you don't want to use the one you have for your trailer plug.

It could be that the earth is not up to the job - contrary to the + and the - signs, if I have remembered my high school chemistry properly the electons come from the -ve side - but in any event there needs to be a good earth. Just put a jumper lead with alligator clips temporarily from the earth wire to a known good earth and see what happens.

It could also be getting too hot, or have a fault that only appears when it gets hot - I have just had that very conversation with Pioneer about a head unit that makes pops and crackles on CD and USB input, only on longish journeys, and not at all on FM and AM. they have agreed to replace it - however when I was removing it to take back, I was surprised at how warm the head unit was - an installer suggested that a dry joint may have been failing when it got hot

[simongnz]

My GQ's loom doesn't supply an earth wire to the head unit at all - it's earthed via the Nissan mounting rails directly to the chassis. I could be wrong but I'd suspect that it is earthed pretty well this way.

From what you're saying, connecting the stereo directly to the trailer plug wiring would be the best bet by the sound of things.

[simongnz]

I got it all working. Required connecting a feed directly from the lower battery (the one with the negative pole earthed to the chassis) to the always-on 12v+ on the head unit. The switched 12v+ can still come from the factory loom. If you're wiring up like this, you'll need an evencharger installed to ensure one battery doesn't start getting over charged. Luckily I had one of these already fitted.

Thanks everyone for all your help.