Hi guys,


I've got that yellow ABS light coming and going, but for the last 3 months it has been on all the time. The red break light has been working like it should, i.e. it lights up when I turn ignition on and then goes off in few seconds (yellow ABS light stays on). In addition, from yesterday on another problem appeared. When I turn on ignition there is no yellow ABS light, but the red break light light up and goes off as it should. After some ten seconds from starting the engine both the yellow ABS and red break ligh light up, and stay on. I took the car to my mechanic, and his tester cound not find the ABS module at all. So it is dead or just missing come connection. This now needs some proper investigations, fuses are ok though..


For the ABS light I checked the wheel sensors connectors, as they appear to collect dirt etc. They all seem ok to me. Then I followed the wiring under the hood, and found some mysterious stuff close to the relay box (see photos in links). What is that blue connector? Or is it a base for a some relay? This is something home made or garage installation I believe. That brown wire goes to ABS unit/pump wires connector down there behind the battery (didn't check more closely yet since it seems a bit nasty place to reach). Blue wire comes with 12V from below the fuse box when ignition is on (it has been connected to some other wire that gets 12V from fuse box when ignition is on) and the yellow one grounds the relay. So the relay operates the brown and that green/red wire. The "central" wire in that blue connector goes to ground, others I have no clue. Relay works (tested).





So, anyone any idea what this stuff might be about?



http://www.nuottajarvi.com/c64/connector1.jpg
http://www.nuottajarvi.com/c64/connector2.jpg
http://www.nuottajarvi.com/c64/relay1.jpg
http://www.nuottajarvi.com/c64/wires1.jpg

 

Right, some progress..

Found two broken wires (ending to ABS unit connector). Other wire was one of the wheel sensor wires, and the other one is the one that has been replaced with that brown mystery wire described earlier.

Fixed both the wires (well, the brown replacement wire is still there in place). 12V (topmost two pins) come ok, and grounds (two bottom ones) are ok. In photo the right hand side row are the wheel sensors. Left hand side is something I don't know yet (3 wires only). Topmost goes to ground, middle one has been changed to that brown wire, and the bottom one is something I don't know.. yet.

The question is, should I see some voltage in that "brown" wire or not. I mean when connector is in place and car is running.


http://nuottajarvi.com/c64/ABS_bad_wires2.jpg

http://nuottajarvi.com/c64/ABS-connector.jpg

http://nuottajarvi.com/c64/ABS-connector2.jpg

 

Problem solved.

There was one broken wheel sensor wire --> fixed that. The other wire that had got broked already before me, and that was fixed that brown "mystery wire" is ABS switching voltage (when ignition is on). Now in this the problem was that black relay which was failing, i.e. not enough voltage through it, though you could beep it ok with a multimeter. The blue relay base is a base for some relay that has been there or has not been there, can't know. Anyhow, when the original switching voltage wire had got broken, someone just passed the whole wire, replaced it with that brown one and took a free available switching voltage from this blue relay base and connected it to that substitute wire. That black bonus-relay was, after all, just an extra relay with no real meaning.

The only problem then was to realise that after fixing all wires and voltages I had to take the car to the garage to reset the error. But, now all works ok.

 

- nicely diagnosed/repaired nuottis.