When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
my 94 has the following codes, h21, h23, h37. these codes are are in the abs computer system. i have a service abs and a service asr on the dash. any help would be appriciated. thanks
21 & 23 are for the right front wheel sensor - 37 is the left rear sensor. Diagnosis ususally involves a special tool. Other than checking for obvious damage, I wouldn't know what else to recommend.
I don't think so. From what little I know, sensors are an indication of vehicle speed based on voltage signals determined by the air gap between the toothed gears. Traction Control/ABS ECM uses this information to determine if the vehicle is skidding or if a wheel has locked up and pulses the brakes to control wheel spin. It could be the wiring - no or partial signal due to an open or poor mating at a connector or a damaged sensor. I think the 21 will only be generated if the vehicle is moving. The other two can be indicated with the key on or vice versa.
21 & 23 are for the right front wheel sensor - 37 is the left rear sensor. Diagnosis ususally involves a special tool. Other than checking for obvious damage, I wouldn't know what else to recommend.
:iagree: However, since they are all proceeded by "h" they are history codes. Try pulling the battery cable (neg) for a min. or two, reconnect and go for a drive to see if they reappear.
These codes should turn on the Service LTPWS light in the DIC (driver information center). Does the Service LTPWS light come on when you turn the key on? If it does not then the bulb is burnt out or as it was in my case, someone pulled it out :smash: .
the low tire pressure sensor is very interesting? i don't belive i have these....i thought this was an option? do you think someone pulled the bulb on me? this still does not explain the recent service abs and service asr lights?
These codes should turn on the Service LTPWS light in the DIC (driver information center). Does the Service LTPWS light come on when you turn the key on? If it does not then the bulb is burnt out or as it was in my case, someone pulled it out
Please, disreguard this post. I see now :bb that you are having trouble with wheel speed sensors if you have replaced the offending sensors and continue to see the DTC (diagnostic trouble code) could be the circuit or the ASR/ABS module.
If you don't have the GM service manual get one, http://www.helminc.com best 90$ I've spent!! :seeya