GMC Troubleshooting Questions? Ask a Mechanic for Answers
what year and model is this ?
are there any history codes set in the ABS computer ?
any codes set in any computer at all ?
are you sure there are NO codes current or history set in any computer at all ?
knowing if there are any codes set in the history are key to know which area we are having this problem
these 2003 trucks doing this end up being the grounds under the drivers door on the outer frame rail being loose or one of the front wheel abs speed sensors is bad sending an intermittent wrong speed signal to the ABS computer triggering all the lights
once you know the code you will know exactly which sensor or if that ground could be bad off the code set
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