ABS malfunction

[Greg Albers]

Hi all
The abs light is on on my dash. I pulled the codes and the only one shown is bad LR sensor. Sensor checks out OK but I still have light.
Should I be able to hear the abs pump self checking when I turn the key to the on position? I have pumped the brake pedal with the switch off and then turned the switch to the on position several times and do not hear anything from the pump. I have a factory manual for my car but do not have the pinout connector to test the circuits. I have a 1990 L98 coupe.
Help!
Greg;help

 

[86PACER]

Should I be able to hear the abs pump self checking when I turn the key to the on position? I have pumped the brake pedal with the switch off and then turned the switch to the on position several times and do not hear anything from the pump.

No. The pump only primes each time you start the motor and reach 4 MPH either in reverse or foward. It does nothing with motor off regardless of key position.

Should sound like this. Click below for video sound clip.

Click Here

 

[Greg Albers]

ABS

Thanks, I read somewhere that it self tests when you turn the key on. I don't think mine is self testing at all. The abs light doesn't come on until I start moving but I don't hear the pump. The code that I am getting is bad LR sensor. It is new. I replaced it because of the code. Still have light and same code (35 I think) Guess I will have to find a pinout adapter so I can check the other circuits. Thanks again.

 

[David-F]

It would be helpfull to get a hold of a pin out box but if not you will need to test the circuit to the brake module to check for opens or short to ground. If wiring checks out you will need to check that reluctor ring is still on the spindal, which I'm sure it is I suspect there is a wiring problem some were.

David Fulcher

 

[Greg Albers]

Thanks. I think it is a short somewhere. I have been looking for a pinout box. But haven't found one yet.

 

[waikool93]

Thanks, I read somewhere that it self tests when you turn the key on. I don't think mine is self testing at all. The abs light doesn't come on until I start moving but I don't hear the pump. The code that I am getting is bad LR sensor. It is new. I replaced it because of the code. Still have light and same code (35 I think) Guess I will have to find a pinout adapter so I can check the other circuits. Thanks again.

Your codes wont clear automatically until you go through many operation cycles. Try disconnecting the negative side of your battery for a couple of minutes. That will clear the initial codes - and everything else. Re-start and take a turn or two around the block. If the code(s) reset - then check your grounding and all the plug-ins around your abs computer.

Good luck

 

[gmjunkie]

If it don't Reset after removing neg cable.Clean the Brake dust out of the Reluctor Rings!!!!!!!!! The Brake dust has metal shavings in it and the Rings are magnetic,and wont let the sensor count the teeth on the ring!!!!Makes it give a False reading!!!! Just jack the back up and take a Air hose and Blow the Crap out of them!!!!!!!! I see it all the time!! :cool