PSM and ABS lights that stay ON

[pstarenas]

I have a 2001 C4 CAB w/Tip that has the PSM and ABS lights that stay ON. The PSM switch light comes on before starting engine but doesn't do anything once engine is running.

Problem started after a weak battery was charged. Everything else seems to work fine and car appears to run OK.

Other posts point to MAF but this seems like a strange coincedance that it started after I charged the battery. Could it be as simple as a blown fuse ? Some posts indicate brake light switch could be it but brake lights work fine.

Let me know if you know of other things to try.

[vadim]

I have a 2001 C4 CAB w/Tip that has the PSM and ABS lights that stay ON. The PSM switch light comes on before starting engine but doesn't do anything once engine is running.

Problem started after a weak battery was charged. Everything else seems to work fine and car appears to run OK.

Other posts point to MAF but this seems like a strange coincedance that it started after I charged the battery. Could it be as simple as a blown fuse ? Some posts indicate brake light switch could be it but brake lights work fine.

Let me know if you know of other things to try.

I had same problem with my car , and can't really find what happen ,and how to fix it .I went to dealership ,they told me may be MAF ,be something else .Well ,after I erase this code from computer ,till now it is all gone.Try erase code first ,and then see what happen .

[Reborn996]

I recently had this type of symptom with my 1999 (it has traction control rather than PSM). It turned out during my recent steering rack install that I had broken a wire for one of the speed sensors for the ABS system. If you can run a diagnostic on the ABS system it should tell you which wheel it might be...

David

I have a 2001 C4 CAB w/Tip that has the PSM and ABS lights that stay ON. The PSM switch light comes on before starting engine but doesn't do anything once engine is running.

Problem started after a weak battery was charged. Everything else seems to work fine and car appears to run OK.

Other posts point to MAF but this seems like a strange coincedance that it started after I charged the battery. Could it be as simple as a blown fuse ? Some posts indicate brake light switch could be it but brake lights work fine.

Let me know if you know of other things to try.

[neil.c]

if there is an abs fault that would also generate a psm fault/ failure brake light switch failure usually only generates a psm failure and not abs failure. sounds like a faulty wheel sensor to me

[RFM]

Not agree a faulty brake light switch generate ABS/PSM failure on a C4, the MAF sensor as much.

[ronbonner]

I have a 2001 C4 CAB w/Tip that has the PSM and ABS lights that stay ON. The PSM switch light comes on before starting engine but doesn't do anything once engine is running.

Problem started after a weak battery was charged. Everything else seems to work fine and car appears to run OK.

Other posts point to MAF but this seems like a strange coincedance that it started after I charged the battery. Could it be as simple as a blown fuse ? Some posts indicate brake light switch could be it but brake lights work fine.

Let me know if you know of other things to try.

Strange coincidence do happen like that: I had a similar problem however, it differs slightly in so far as the ABS and PSM on my C4 (MY2000) came on under hard acceleration and would reset after the engine was switched off. It was the MAF but as I was driving to the dealers my alternator failed at the same time! Oh and to just show how coincidence can strike at anytime I called the recovery at 9.11

[pstarenas]

I have a 2001 C4 CAB w/Tip that has the PSM and ABS lights that stay ON. The PSM switch light comes on before starting engine but doesn't do anything once engine is running.

Problem started after a weak battery was charged. Everything else seems to work fine and car appears to run OK.

Other posts point to MAF but this seems like a strange coincedance that it started after I charged the battery. Could it be as simple as a blown fuse ? Some posts indicate brake light switch could be it but brake lights work fine.

Let me know if you know of other things to try.

I had same problem with my car , and can't really find what happen ,and how to fix it .I went to dealership ,they told me may be MAF ,be something else .Well ,after I erase this code from computer ,till now it is all gone.Try erase code first ,and then see what happen .

[pstarenas]

I've tried everything mentioned but with no success. When I pull fuse on PSM control module ligt go off, then back on after a few seconds after putting fuse back in indicating to me it really thinks there's a fault somewhere. There are no error codes showing on code reader.

Any other suggestions ? Car runs great but lights stay on.

[vizcarra44]

I've tried everything mentioned but with no success. When I pull fuse on PSM control module ligt go off, then back on after a few seconds after putting fuse back in indicating to me it really thinks there's a fault somewhere. There are no error codes showing on code reader.

Any other suggestions ? Car runs great but lights stay on.

Are you using a diagnostic scan tool that is more than just basic? I would say at this point you need to analyze the Abs data and see if anything is out of the

normal.

vizcarra44