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My ABS doesn't work. You're shocked, I know. Someone having problems with a Teves MkII is an event wholly unprecedented in the continuity of the human race. I've done quite a lot to figure out the problem. I've read everything I can find here. Jeff's writeup on troubleshooting the system deserves credit for the brakes working as well as they do. However, the source of the problem eludes me still after many years. I don't really expect anyone to have an answer for me. I think it'll just make me feel better to talk about it.
When you turn on the key, the ABS light comes on and stays on. Nothing else happens. The ABS doesn't operate. It won't even give me codes. The OBD scanner gets zeroes, and jumping the pins won't make it blink. (I jumped the correct pins, I assure you.) The answer seems obvious: Bad controller module, right? Of course. That's what I thought. That's why I replaced the module twice. Three modules, all the same. No change in behavior. The behavior I mention next is also common to all three modules, and this is where it gets really weird:
If you short the white ABS light wire to ground (as marked on the diagram below) with the key off, then disconnect the short after you turn the key on, everything works.
The light turns off, the ABS works flawlessly. Stops on a dime and gives you change. I do not know why this ground short trick works. I did not figure this out; some other guy did about ten years ago and I haven't the faintest notion how he did. I would love to ask him but I cannot contact him to do so.
Now, that could certainly be a problem with the module. But that is extremely bizarre behavior and for three random modules to all be afflicted like that defies probability. The fact that the ABS works fine if it starts up successfully seems to indicate that the modules are, in fact, fine. It seems more likely that something else is causing the module to simply fail to initialize. The relay! Of course. The relay isn't powering the module on correctly. Is what I said before changing the relay and testing the relay connector and determining both are functioning properly. I cannot find anything that seems faulty. The pressure switch, the fluid level switch, the valves, the wiring itself, the fuses, all seem okay. And again, the fact that the system works perfectly with the short trick seems to prove that there are no faulty parts. Which leads one to a conclusion that is as baffling as it is frightening: That something somewhere outside the ABS system is interfering with the ABS somehow. How do I approach this? I dunno. I probably can't.
So there's my story of woe. Perhaps, if nothing else, you can feel better about your own lot having read it and said "I'm glad that's not me." Indeed, the agony of that yellow light searing my retinas with a constant reminder of my impotence and ignorance in the face of a problem that could probably be fixed in ten minutes if only I understood it is something I wouldn't wish on anybody. Thank you for your kind attention as I scream into the sun.
![[Image: S0cjysv.jpeg]](https://i.imgur.com/S0cjysv.jpeg)
When you turn on the key, the ABS light comes on and stays on. Nothing else happens. The ABS doesn't operate. It won't even give me codes. The OBD scanner gets zeroes, and jumping the pins won't make it blink. (I jumped the correct pins, I assure you.) The answer seems obvious: Bad controller module, right? Of course. That's what I thought. That's why I replaced the module twice. Three modules, all the same. No change in behavior. The behavior I mention next is also common to all three modules, and this is where it gets really weird:
If you short the white ABS light wire to ground (as marked on the diagram below) with the key off, then disconnect the short after you turn the key on, everything works.
The light turns off, the ABS works flawlessly. Stops on a dime and gives you change. I do not know why this ground short trick works. I did not figure this out; some other guy did about ten years ago and I haven't the faintest notion how he did. I would love to ask him but I cannot contact him to do so.
Now, that could certainly be a problem with the module. But that is extremely bizarre behavior and for three random modules to all be afflicted like that defies probability. The fact that the ABS works fine if it starts up successfully seems to indicate that the modules are, in fact, fine. It seems more likely that something else is causing the module to simply fail to initialize. The relay! Of course. The relay isn't powering the module on correctly. Is what I said before changing the relay and testing the relay connector and determining both are functioning properly. I cannot find anything that seems faulty. The pressure switch, the fluid level switch, the valves, the wiring itself, the fuses, all seem okay. And again, the fact that the system works perfectly with the short trick seems to prove that there are no faulty parts. Which leads one to a conclusion that is as baffling as it is frightening: That something somewhere outside the ABS system is interfering with the ABS somehow. How do I approach this? I dunno. I probably can't.
So there's my story of woe. Perhaps, if nothing else, you can feel better about your own lot having read it and said "I'm glad that's not me." Indeed, the agony of that yellow light searing my retinas with a constant reminder of my impotence and ignorance in the face of a problem that could probably be fixed in ten minutes if only I understood it is something I wouldn't wish on anybody. Thank you for your kind attention as I scream into the sun.