P38 new problem with abs and traction fault

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I found that with trying to pay bills and purchase things online.
Good news, I just borrowed my wife's ASUS Win 11 laptop and RAVE ran straight away from an XD memory card. Unlike Win 10 I didn't need to use compatibility mode. The EAS suite from RSW will also run but Net Framework has to be downloaded. So I now have no fear of updating to Win 11 :D
If anyone is stuck for a copy of RAVE, I would be prepared to put it on a memory card and post out for the cost of the card and postage.
 
Good news, I just borrowed my wife's ASUS Win 11 laptop and RAVE ran straight away from an XD memory card. Unlike Win 10 I didn't need to use compatibility mode. The EAS suite from RSW will also run but Net Framework has to be downloaded. So I now have no fear of updating to Win 11 :D
If anyone is stuck for a copy of RAVE, I would be prepared to put it on a memory card and post out for the cost of the card and postage.
Now, funny you should say that because after months of NOT working under Win11, after last weeks major Windows update it is now working again! Happy Days! :dance:
 
There are also work-arounds for older laptops that don't have the TPM (trusted platform module), which is otfen the reason for the incompatability. The other thing is older graphics chips, or not enough memory.
 
Hi All
Im back again with an update, but 1st Happy New Year to you all, I had a new brake light switch fitted which was dodgy but made no difference to my problem, but at least brake lights work correctly!! after replacing the master cylinder and re-bleeding the brakes correctly with no joy ive now put a replacement ABS pump and accumulator on, I was told of you inserted a blunt object into the accumulator there should be no movement as 80bar should be in there, my original one moved about 10mm-15mm so hence i replaced it, the one I put on had about 5mm of movement so probably still not perfect, ive sent my old one off for a refurb, still got the ABS and TC lights on!! the wiring was checked at the same time as the brake light switch was replaced and no faults were found and the auto electrician said all was pointing to the pump and accumulator hence that was done, this is getting tiresome now.
I'll wait until accumulator comes back and fit it and re-bleed the system, if lights still on i wont know where to look, so the matches will probably come out, way way to complicated, nice drive but ive never had these problems before, anyone want the challenge of fixing it, Im in Derby Derbyshire?
Cheers
Maxderby
 
Hi All
Im back again with an update, but 1st Happy New Year to you all, I had a new brake light switch fitted which was dodgy but made no difference to my problem, but at least brake lights work correctly!! after replacing the master cylinder and re-bleeding the brakes correctly with no joy ive now put a replacement ABS pump and accumulator on, I was told of you inserted a blunt object into the accumulator there should be no movement as 80bar should be in there, my original one moved about 10mm-15mm so hence i replaced it, the one I put on had about 5mm of movement so probably still not perfect, ive sent my old one off for a refurb, still got the ABS and TC lights on!! the wiring was checked at the same time as the brake light switch was replaced and no faults were found and the auto electrician said all was pointing to the pump and accumulator hence that was done, this is getting tiresome now.
I'll wait until accumulator comes back and fit it and re-bleed the system, if lights still on i wont know where to look, so the matches will probably come out, way way to complicated, nice drive but ive never had these problems before, anyone want the challenge of fixing it, Im in Derby Derbyshire?
Cheers
Maxderby
Needs diagnostics or you are just p1ssing in the wind. The lights do not go out until the car is moving at above 5mph. It could just be a wheel sensor.
 
hi
thanks for your comments, its had more diagnostics than you can shake a stick at, nobody seems to know about setting the brake light switch? could you give more information please
thanks
Maxderby
 
hi
this was the last scan, i know you will all jump on the last line, but we cleared all faults ran it around and re checked the last line had gone but the others are constantly there, like i said last time it was checked by sparky he said wiring was good and all pointing to abs pump as mentioned, i can throw more money at by putting rear abs sensors on it but everything so far seems nonesense, no matter what you put on same faults, that sensor hasnt shown again, had the same with front left, put new sensor in, it said fault was still there, cleared fault twice and problem has never come back on diagnostic equipment, if the faults are ghosts you could be chasing them for ever, is BECM to blame just throwing up random rubbish, at this rate mot will be due and will fail on some random rubbish, car stops fine but oooooooo theres a light on so got to fail it, how did we cope with none abs vehicles, ive had many vehicles and aint crashed one of them, will start start to look if you can frig the abs light and take the TC off as i think early ones didnt have it or need it
cheers
Maxderby
 

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sorry meant to say front right sensor but both sensors been replaced, somebody said on this thread you need a flashy scope to check them and i dont have one
, whats the point of buying new sensor if they can be naff from new and you cant check them before installing them
 
hi
thanks for your comments, its had more diagnostics than you can shake a stick at, nobody seems to know about setting the brake light switch? could you give more information please
thanks
Maxderby
From memory, the plunger is pulled up as far as it will go it is then set by operation of the brake pedal. Others will soon correct me if I have got that wrong.
hi
this was the last scan, i know you will all jump on the last line, but we cleared all faults ran it around and re checked the last line had gone but the others are constantly there, like i said last time it was checked by sparky he said wiring was good and all pointing to abs pump as mentioned, i can throw more money at by putting rear abs sensors on it but everything so far seems nonesense, no matter what you put on same faults, that sensor hasnt shown again, had the same with front left, put new sensor in, it said fault was still there, cleared fault twice and problem has never come back on diagnostic equipment, if the faults are ghosts you could be chasing them for ever, is BECM to blame just throwing up random rubbish, at this rate mot will be due and will fail on some random rubbish, car stops fine but oooooooo theres a light on so got to fail it, how did we cope with none abs vehicles, ive had many vehicles and aint crashed one of them, will start start to look if you can frig the abs light and take the TC off as i think early ones didnt have it or need it
cheers
Maxderby
That suggests the ABS ECU is suspect. As far as I know, all P38's had ABS with early having 2 wheel traction control and later ones 4 wheel TC.
To pass the MOT, the ABS, TC and parking brake lights need to illuminate and then extinguish above 5 mph. It's easy enough to use a 555 timer module to briefly put he lights on but better to fix the problem. Have you checked the ABS ECU connector for corrosion?
 
Sorry @maxderby, here's my 2P-worth on ABC/TC fault (I had it and did get rid of it).

1. Twice! I got this fault when the Alternator failed. Change of alternator and no more fault.
and when it wasn't the alternator.....
2. There is a known fault that develops with the WABCO-D 4-wheel ABS ECU. It is LHR Short to another sensor and it can be repaired. But, if you have swapped yours and mates ECU's over and the fault is still with your car then it's the ABS unit or the wiring I would say.
When mine wasn't the alternator...... it was a failed sensor.
So, at each ABS sensor plug looking upstream to the ABS unit you should see at least 5v across the connector, check all 4 ABS sensor connector sockets..... and.. at each Sensor should be about 1k or 1.2k Ohms (IIRC) when you look directly across the sensor with it not plugged in to its socket. Check the resistance of each sensor to see if there is one that is different from all the rest.

Best of luck mate. :)
 
hi
thanks again, does this mean when your looking for 5v that the lead is unplugged from the sensor so thats out of the equation and your checking in effect the wiring loom for 5v, then check each sensor lead on its own for the ohms reading? as for the alternator, wouldnt the battery light be on or the battery not charging? what is a LHR short, not a sparky but can usually follow instructions:)
many thanks
Maxderby
 
hi
thanks again, does this mean when your looking for 5v that the lead is unplugged from the sensor so thats out of the equation and your checking in effect the wiring loom for 5v, then check each sensor lead on its own for the ohms reading? as for the alternator, wouldnt the battery light be on or the battery not charging? what is a LHR short, not a sparky but can usually follow instructions:)
many thanks
Maxderby
LHR = Left Hand Rear sensor. 5 volts at the sensor plug is with it unplugged from the sensor, it's not reliable as no current is being drawn. Testing with ohms from the sensor plug to the ECU is what I do.
Alternators can fail in many different ways. Failure in the diode pack may not stop it charging so the light goes out but the output may be full of spikes that can affect ECU's.
 
hi
thanks again, does this mean when your looking for 5v that the lead is unplugged from the sensor so thats out of the equation and your checking in effect the wiring loom for 5v, then check each sensor lead on its own for the ohms reading? as for the alternator, wouldnt the battery light be on or the battery not charging? what is a LHR short, not a sparky but can usually follow instructions:)
many thanks
Maxderby
When I diagnosed mine I put my Voltmeter on DC volts across the 2 pins of the socket that the ABS sensor plugs into on the car's wiring loom. I was surprised to find not 12v (as everybody had told me to expect) but 5.3v. Now, 5.3v is a fairly early style of solid-state logic circuits, so it sort-of "figures" for an old car like this. So, if you have 5.xVolts of power going into the ABS transducer/pickup at the wheel to power it, what sort of resistance should the pickup have. I measured all 4 of mine and all except the failing corner were 1200 Ohms or thereabouts. So the clues were there and a "NEW" front wheel ABS sensor fixed the problem. I keep a permanent front wheel spare now as they are both the same. The two back one's are not the same I think. Same logic, same physical makeup but differing cable lengths back to their sockets.
 
cheers folks, I will try these tests asap, I have to rely on friends letting me use there space as not crawling on floor in the wet!! how do you test an alternator that is apparently working?
 
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