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ABS Light

Heath

By Heath
in Ask A GM Technician

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Heath Enthusiast

Heath

Posted
Posted

Back in January I had the ABS light coming on and the brake booster kicking in at low speeds or when beginning to stop, changed the front ABS speed sensors and solved problem. Now at highway speed of 60 mph or greater the abs light comes on and the alarm dinger that is identical to the buckle seat alarm comes on goes off a few miles later it comes again. It usually has to be driven about 6 to 8 miles before this cycle begins.  Can anyone help me diagnose this problem? My mechanic put his computer on it and it's not throwing a code and it has us puzzled.

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

If the light came on, then there's a code in memory. Try another scan tool and report back with that code.

certified22 Enthusiast

certified22

Posted
Posted

On the back of the engine block passenger side coming from the main wiring harness on the fire wall will be a single ground wire that goes to the back of the engine block it’s kinda hard to get to and harder to see but the connector is damaged or loose and is causing your issue undo the wire and relocate it to the ground pin on the fire wall that has the braided ground strap coming from it this will solve your issue for sure it sounds to simple but believe me it works have a great day

Heath Enthusiast

Heath

Posted
  • Author
Posted

Adam,

Thank you so much for your input!! I would like to ask you to do me a huge favor!!?? Please snap a couple of pictures of yours and its location so that I know exactly what wire I'm looking for so I don't mess up and pick the wrong wire. I would appreciate that very much!

Regards,

Heath

Heath Enthusiast

Heath

Posted
  • Author
Posted

Have you had opportunity to  take pictures?  Or have I missed them?

Thanks

Heath

 

certified22 Enthusiast

certified22

Posted
Posted

I posted original photo then photo after I marked it up couldn’t get any good ones of the bolt on back of block I’ll try again though if this doesn’t help

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