Tried searching around but couldn't find anything on this issue. 99 2500 with 4WD 4 wheel abs, everything on the dash works, cruise works and brake and abs light on.
Every time I try to pull codes from the ABS it will give me a different one, I will key on check codes, get 1-2 codes, key off and repeat, sometimes I will get different codes to pop up and the other codes go. Also when I key on I hear the pump turn and thump then nothing. Of course ABS won't activate too.

I have gotten code 84 (mismatched VIN), 53 (Shorted ISO Solenoid Or Open ECU), 38 (Wheel Speed Error), 65 (Open Power Relay Contacts) and 37 (Erratic Sensor Signal-Rear).

Where should I go from here? I have a tendency to pull out the parts cannon but I don't want to do that with this one.

Thanks for any help.

 

Done any work on the brake system/abs before? The vin mismatch thing kinda indicates that.... If not, I would think the controller is going belly up... of course, the most expensive part of the system......

 

I haven’t but I did buy this truck with the abs/brake light on. Now that winter is coming up I’d like to get it working. Do the abs modules have to be programmed to the ecm? Now that your mentioning the vin mismatch I’m thinking that maybe the previous owner threw a new module on it without programming it but at the same time I would think it would throw that one code instead of all of them.

Of course it’s the most expensive part, it’s how it always goes!

 

Question becomes, what parameters does the VIN set in the module..... Should be able to flash it to the correct vin, with the right scanner..... (high zoot commercial grade feller....)