Gord Wedman

Well-Known Member
I recently sold my 99 Autobiography to a fellow who was looking for a cheap 4x4 as he lives in a hilly area. The car was in very good condition inside and out. He also liked the roof rack which could carry his kayak. I had bought this car to take off the factory Warn winch installation and swap it onto my offroader. After fixing a few things on the car and driving it a bit over over the summer it seemed to be fine. Before buying the car we test drove it twice, maybe for an hour and all was good. He drove it home, 50km, and no problems. Two days later the ABS and TC lights came on and the speedo stopped working.

I tried scanning for ABS codes with my Hawkeye Total but could not establish a connection. I could scan other modules. Yesterday I took the ABS module from my other 99 and put it in his car. I know this module is good as the other car has no issues and I was able to scan it while it was in the offroader. In his car I once again could not establish a connection so the problem does not seem to be the module.

I have a couple of questions in addition to "what the hell is going on".
1. Does a scanner like the Hawkeye or Nanocom look for trouble codes in the actual module or are these all stored in the BeCM?
2. If the codes are stored in the BeCM does the communication problem indicate a BeCM problem?
3. Do any wires relevant to this problem run through the connectors behind either kick panel? We have not looked there yet.

Hope you folks can help. We are bummed out as we cannot determine what is causing the problem. Thanks for any suggestions.
 
ABS diagnostic shares the same K Line with BECM, Engine, HEVAC and Cruise, so the diagnostic connector sounds ok.

1. The codes are in the ABS ECU itself.
2. N/A
3. Yes look for C0067 behind RH kick panel.

As far as I know, if one sensor fails there will be ABS fault, but speedo should still work as my understanding is that uses an average of all the sensors. Other's might know different ??
 
I recently sold my 99 Autobiography to a fellow who was looking for a cheap 4x4 as he lives in a hilly area. The car was in very good condition inside and out. He also liked the roof rack which could carry his kayak. I had bought this car to take off the factory Warn winch installation and swap it onto my offroader. After fixing a few things on the car and driving it a bit over over the summer it seemed to be fine. Before buying the car we test drove it twice, maybe for an hour and all was good. He drove it home, 50km, and no problems. Two days later the ABS and TC lights came on and the speedo stopped working.

I tried scanning for ABS codes with my Hawkeye Total but could not establish a connection. I could scan other modules. Yesterday I took the ABS module from my other 99 and put it in his car. I know this module is good as the other car has no issues and I was able to scan it while it was in the offroader. In his car I once again could not establish a connection so the problem does not seem to be the module.

I have a couple of questions in addition to "what the hell is going on".
1. Does a scanner like the Hawkeye or Nanocom look for trouble codes in the actual module or are these all stored in the BeCM?
2. If the codes are stored in the BeCM does the communication problem indicate a BeCM problem?
3. Do any wires relevant to this problem run through the connectors behind either kick panel? We have not looked there yet.

Hope you folks can help. We are bummed out as we cannot determine what is causing the problem. Thanks for any suggestions.
Codes are stored in the module, no codes are stored in the BECM. Water ingress causing corrosion in the connector is a possibility. Low battery volts is another possibility.
The speedo is driven from the ABS.
 
ABS diagnostic shares the same K Line with BECM, Engine, HEVAC and Cruise, so the diagnostic connector sounds ok.

1. The codes are in the ABS ECU itself.
2. N/A
3. Yes look for C0067 behind RH kick panel.

As far as I know, if one sensor fails there will be ABS fault, but speedo should still work as my understanding is that uses an average of all the sensors. Other's might know different ??
I think you are correct about the sensors for the speedo.
 
I never saw the speedo stop working for one sensor, but then if all 4 went down maybe that would do it... or if the ABS ECU was not receiving power at all...does the brake pump work? MF3 ? F24/27? RL2/17?
I assume the whole binnacle receives power? ie when you say that the speedo does not work, you just mean that the needle does not move?
 
Thanks for the replies. Much appreciated.
I will pass along the recommendation to check behind the kick panels. It would seem there is a bad connection somewhere.
The buyer told me his research suggested the speedo should get a signal as long as at least 1 ABS sensor is working. It would be highly unlikely for all 4 of them to stop working at the same time so it must be something else. The speedo reads zero all the time.
 
I never saw the speedo stop working for one sensor, but then if all 4 went down maybe that would do it... or if the ABS ECU was not receiving power at all...does the brake pump work? MF3 ? F24/27? RL2/17?
I assume the whole binnacle receives power? ie when you say that the speedo does not work, you just mean that the needle does not move?

+1. Sounds like no power to ABS control unit so fuse or relay would be my first port of call or check the input voltage to the unit at least.
 

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