This week's challenge seems to be to find a way of ensuring our new stereo will turn on and off when it should and stay turned off when we turn it off!
I've posted elsewhere about paying a bit more for a head unit with a dedicated Barchetta wiring harness and adapter BUT it turns out that even these won't work if your car's wiring is not as per the factory manual's wiring diagram! I've no idea why our car seems to be different but here goes.
The wiring diagram for the radio (head unit) is attached (supplied by @Wiltshire Chris here: https://www.fiatforum.com/downloads/service-manual-restructured.410/ . Thanks again). It shows that there are two constant lives coming out of the junction box (red and black) and one live from the ignition circuit (yellow and black). Plus an earth which leads to the car's left side earthing point. There is one other wire that doesn't seem to go anywhere but on our car it is yellow. So far so good and you would think that this would work for a matching wiring harness....
However, our new stereo has never worked properly in terms of only working when the ignition is on, remembering any presets or settings and even staying turned on once you've started the engine. So, I've run a volt meter across the terminals on the car's wiring 'plug' containing all the wires outlined above and the results are confusing....
I've checked as many relevant fuses as I can find and am now completely stuck. I'm waiting for some feedback from the In Care Emporium but am worried that if I share the above information with them, they'll just tell me the problem is with the car and not their dedicated kit.....
If anyone has any ideas on how to get the yellow and black wire from the ignition circuit to actually show some volts when it should, (or indeed any other ideas) I'd be very grateful.
Thanks in advance
UF
I've posted elsewhere about paying a bit more for a head unit with a dedicated Barchetta wiring harness and adapter BUT it turns out that even these won't work if your car's wiring is not as per the factory manual's wiring diagram! I've no idea why our car seems to be different but here goes.
The wiring diagram for the radio (head unit) is attached (supplied by @Wiltshire Chris here: https://www.fiatforum.com/downloads/service-manual-restructured.410/ . Thanks again). It shows that there are two constant lives coming out of the junction box (red and black) and one live from the ignition circuit (yellow and black). Plus an earth which leads to the car's left side earthing point. There is one other wire that doesn't seem to go anywhere but on our car it is yellow. So far so good and you would think that this would work for a matching wiring harness....
However, our new stereo has never worked properly in terms of only working when the ignition is on, remembering any presets or settings and even staying turned on once you've started the engine. So, I've run a volt meter across the terminals on the car's wiring 'plug' containing all the wires outlined above and the results are confusing....
- Both red and blacks are constant lives as expected when tested with the black (which made me think the earth was working properly)
- The yellow and black ignition circuit which I thought was supposed to be live when the key is turned to 'dashboard lights all on' position is dead all of the time when tested with the main, black earth. Tested this with the engine running too and got the same result.
- The solitary yellow wire also shows zero volts when paired with the black earth whether the ignition is on or off.
- If, however, you pair either of the red and black wires with the yellow and black or the yellow wire, the meter shows 12 volts whether the ignition is on or off, so these are making a circuit somehow.
I've checked as many relevant fuses as I can find and am now completely stuck. I'm waiting for some feedback from the In Care Emporium but am worried that if I share the above information with them, they'll just tell me the problem is with the car and not their dedicated kit.....
If anyone has any ideas on how to get the yellow and black wire from the ignition circuit to actually show some volts when it should, (or indeed any other ideas) I'd be very grateful.
Thanks in advance
UF