Replacing factory stereo with new Sony one

Hi all. New member here. I've just purchased a 2002 Citroen C3 LX and decided to replace the stereo. The existing one comprised of two units, a radio cassette and a 5 disc multichanger cd player. The replacement I have bought is a Sony DSX-A400BT along with the PC2-32-4 Wiring Harness. After id connected everything up there is no power at all. There are two wires coming out of the harness that I have no clue where to connect to. One is a short yellow one with a connector on the end and the other is the long red ignition switch one. I stopped at that point and put the old stereo back in as I didn't want to start messing around with wiring and causing a problem. I couldn't see where the two wires could connect to so after a lot of searching I found this forum. I would appreciate any help or advice on where these two wires should go. I can upload pictures of the cars wires but that will have to be tomorrow. Thank you in advance for any help forthcoming. Regards Craig.

Hi Craig

Check you fitting instructions and it will be something along the lines:-

I think the yellow wire will be the permanent live to the new radio. This is present in the car's wiring so will join to another similar wire on the other side of your adaptor wiring harness.

I think the red wire will be a switch ignition feed. The old radio doesn't have one of these so you'll have to connect this to another circuit. I'd suggest the cigarette lighter as it's nearby and the wiring is easy to get at. The bottom centre console comes out with a couple of screws.

If you post a picture of your adaptor and it's wiring diagram this can be checked.

craig1975 wrote:along with the PC2-32-4 Wiring Harness. After id connected everything up there is no power at all. There are two wires coming out of the harness that I have no clue where to connect to

That adaptor you purchased is a generic one that can me made to fit a number of different makes of car but requires you to find the circuits and make the connections yourself.


It is possible to use just a ISO plug set and swap the wires 4 and 7 over in the power ISO plug, this is possible on your 2002 model.
If your PC2-32-4 has bullet connectors on the red and yellow (check the pin numbers too), connect the red to yellow and the yellow to red to make the lead a 'pin 4 and 7 iso swap over lead' that is specific to the C3 2002-2005ish in a quick and dirty hack

Missing Lincs suggestion is a much better way, adding extra fuses and tapping into power circuits, but does require a fair bit more work on the part of the fitter.

Thanks to both of you for the replies. I'm adding two pictures so that you can see what i'm working with.

C3driver52 wrote:If your PC2-32-4 has bullet connectors on the red and yellow (check the pin numbers too), connect the red to yellow and the yellow to red to make the lead a 'pin 4 and 7 iso swap over lead'

Its the sony one that has the swap over bullets, so use this one only.

That should give you power and speakers connection to the C3 and the Sony. No other functions like remote stalk or radio frequency on the dashboard display.

Just use only this lead in the configuration I mentioned above after checking red and yellow go to 4 and 7 pin positions because if they are not correct you can do damage to the car.

Thanks for the reply and diagram. The wires were in the correct pins as you stated. I've done that now and connected it to the PC2-32-4 harness and taken a picture to show you to make sure i'm on the same page as you.

craig1975 wrote:Thanks for the reply and diagram. The wires were in the correct pins as you stated. I've done that now and connected it to the PC2-32-4 harness and taken a picture to show you to make sure i'm on the same page as yo

Thanks for checking. Its well worth checking to avoid costly sparks and flashes.

This is what I was trying to get at:
This way you don't have that extra red wire that seems to go nowhere and there is less cable to hide behind the radio.

I wasn't expecting the Sony lead to have an easy way to swap 4 and 7 over - the red and yellow, but it does so use that and the extra PC2-32-4 is not required

Thanks for the swift reply. Would the Sony harness connections fit the C3 connections without the extra harness? The stereo came from a friend. He sold the car and for the life of me I can't remember what make it was.

craig1975 wrote:Thanks for the swift reply

No problem.

craig1975 wrote:. Would the Sony harness connections fit the C3 connections without the extra harness?

To me, they look like they will, but you know what they say about the lemon? You have to suck it to see.

The connectors supplied by radio manufacturers are often ISO standard and the early C3 fits that standard size plug but the wiring is wrong (the swap 4 & 7 needs to be done to make it ISO electrically correct too).

If you wanted to try, plug the plug of the unused PC2 lead into its socket, do both of the PC2 leads, so you end up with a loop of PC2 lead. You see what you have just proved?

The connectors supplied by radio manufacturers are often ISO standard and the early C3 fits that standard size plug but the wiring is wrong (the swap 4 & 7 needs to be done to make it ISO electrically correct too).

Thanks again. Would I need to join the red ignition wire on the harness to the yellow wire on the harness? The red has a male bullet and the yellow female. Sorry for all the questions but its years since I've fitted a car stereo. Also sorry if I've done the quote thing wrong.