996 Turbo 2003 ABS & PSM wiring diagram please

[Matt Seabrook]

A mate is having problems with his turbo and PSA and ABS lights coming on intermittently. I would like to be able to do some testing on it for him but need a wiring diagram. Can anybody help please?

[Rockster]

Matt Seabrook said:

A mate is having problems with his turbo and PSA and ABS lights coming on intermittently. I would like to be able to do some testing on it for him but need a wiring diagram. Can anybody help please?

Unlikely to be electrical in nature unless you can find signs of water in the cabin -- check the body water drains -- or evidence mice have been gnawing on the wiring.

The battery can be getting weak, or another source of seemingly unrelated and inexplicable PSA and ABS issues is a bad MAF.

Oh, my tech friends tell me sometimes just loosening the bolt that holds the battery cable to the car then retightening this can help cure electrical like issues.

[Pope]

Check the intake for leaks; especially the small hoses on the y pipe just before the throttle (onto the n75 valve / boost cycle valve)

If the fault is a front end speed sensor and it stays on the same side after swapping the sensors left to right the loom in the arch is a known weakpoint and available as a repair section

Edited by Pope on Saturday 3rd May 22:59

[dazren]

Pope said:

Check the intake for leaks; especially the small hoses on the y pipe just before the throttle (onto the n75 valve / boost cycle valve)

If the fault is a front end speed sensor and it stays on the same side after swapping the sensors left to right the loom in the arch is a known weakpoint and available as a repair section

Edited by Pope on Saturday 3rd May 22:59

Had this issue done on my 80k mile 02 turbo at OPC Bristol a few weeks ago. Bingo!

[Matt Seabrook]

I have smoke tested the intake system and no evidence of leaks from that test although the PCM has pinged a MAF fault. The car has only just had a genuine MAF sensor fitted not by me though and we are now having these faults. Thanks for the pointers so far.

Matt

[Matt Seabrook]

Also the only fault code that we could get from the ABS was a brake light switch. My mate fitted another switch. It still had the safe fault reappear. When he brought it to me I tested both switches and both seemed to work as expected.

[NBTBRV8]

I can probably email it to you if you still need it. PM me.