ABS light on
Thread Starter
Instructor
Joined: Nov 2006
Posts: 188
Likes: 0
From: Ripon CA
ABS light on
When I start the car the ABS light come on then goes off. After driving for a short while the light will come on. I'm running 17x11 rears and 17x9.5 in the front. This is on a 91 vette with L98. Braking seems fine with no dragging. Not sure where to start. Any ideas would be helpful.
This is actually on a car I recently purchased and don't know the history. Is there any harm in driving it if I unplug one of the connectors on the ABS unit which makes the light not come on?
Thanks,
mark
This is actually on a car I recently purchased and don't know the history. Is there any harm in driving it if I unplug one of the connectors on the ABS unit which makes the light not come on?
Thanks,
mark
Thread Starter
Instructor
Joined: Nov 2006
Posts: 188
Likes: 0
From: Ripon CA
I forgot to add. After the ABS light goes off and I start to move forward I do get the ABS activated light, I hear the light whir from the unit and then the Service ABS light come on.
Mark
Mark
Race Director
Joined: Dec 2002
Posts: 13,348
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by cyclist7531
Is there any harm in driving it if I unplug one of the connectors on the ABS unit which makes the light not come on?
Larry
code5coupe
Thread Starter
Instructor
Joined: Nov 2006
Posts: 188
Likes: 0
From: Ripon CA
The car is a 1991.
Here is what happens:
1. Turn ignition key and ABS light come on then goes off as it should
2. Start car and I hear the ABS pump do its thing and then the ABS activated light come on then goes off.
3. Start driving and then the Service ABS light comes on
This car has aftermarket cross-drilled rotors and 17x11 AFS wheels in the back.
I came across this when I noticed no ABS light at all, did some digging (I know I should have caught this but I didn't -as I beat myself up) and found that one of the ABS harnesses was upplugged under the rear storage comparment near the ABS unit. Once I plugged in the harness this is what occurred.
Since it only comes on once I start moving I'm wondering if it could be a wheel speed sensor?
mark
Here is what happens:
1. Turn ignition key and ABS light come on then goes off as it should
2. Start car and I hear the ABS pump do its thing and then the ABS activated light come on then goes off.
3. Start driving and then the Service ABS light comes on
This car has aftermarket cross-drilled rotors and 17x11 AFS wheels in the back.
I came across this when I noticed no ABS light at all, did some digging (I know I should have caught this but I didn't -as I beat myself up) and found that one of the ABS harnesses was upplugged under the rear storage comparment near the ABS unit. Once I plugged in the harness this is what occurred.
Since it only comes on once I start moving I'm wondering if it could be a wheel speed sensor?
mark
Thread Starter
Instructor
Joined: Nov 2006
Posts: 188
Likes: 0
From: Ripon CA
Hmm, The ABS Activated light come on then goes out as it should. Only when I start moving does the Service ABS light come on. I would think it it failed the self-test the Service ABS light would not go out after it goes through it's diagnostic and ABS activated light comes on then off.
Mark
Mark
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have you checked the brake fluid level in the mastercylinder?...I know it sounds crazy but as I was buying my ZR-1 the ABS light came on it. I had driven it once and was driving it again when this happened. I had already made an offer on it, so the owner and me go to a chevy dealer and inguire what might be the problem. They thought probably a wheel sensor or the main unit. I pulled my offer and made a much lower one and bought it. Hauled it home....check the brake fluid and it was low....topped it off and haven't had a bit of trouble since.....that was almost 2 years ago now.
Thread Starter
Instructor
Joined: Nov 2006
Posts: 188
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From: Ripon CA
Well, I've got an update on the codes. It looks like it is throwing a code 21 and 22 for the right wheel speed sensor, however when checking the sensor and wheel it appears to be putting out the right signal. Thinking of backtracking the wiring until I eliminate that before trying to replace the EBCM - unless anyone has any other ideas?
Mark
Mark