Traction control / ABS problem 97 STS

[97bobsts]

I just had the engine changed, Replaced the trans fluid and filter (did not flush - just drained and filled). When the car gets to 70 mph the stability reduced message appears along with the abs and traction control warning lights. I stop the car, shut it off, restart it and everything is fine...Traction control works fine and all - until I reach 70 or so mph. It will do this as many times as I am willing to try. I had trouble with the car not starting the other day, so I tightened the battery cables - they were a bit loose, but I am still having the problem. Codes C1232, C1233 and C1255 are in history. Any ideas?

[jhall]

97bobsts,

I believe these are the code descriptions:

DTC C1232 LF Wheel Speed Circuit Open or Shorted

DTC C1233 RF Wheel Speed Circuit Open or Shorted

DTC C1255 EBTCM Internal Malfunction

Based on the C1255, you might be experiencing a grounding or a connection problem. There is a ground wire that connects the TC/ABS module to the car frame. Look at the end of the "motor" housing on the TC/ABS module. One of the assembly studs has the ground lead attached. Check this wire along with the left and right wheel sensor wires which may have been pulled loose. I belive you can see / access this easier if you look under the car (driver's side) by removing the wheel splash guards.

Make sure you completely check the ground lead assembly from the battery. Pull off the rubber cover so all connection harward at the battery end can be examined. Check the main ground lead and terminal at the engine to make sure it is still intact.

Secondly, check the main connector on the TC/ABS module. This is a bail type of connector that uses a lever to disengage / engage the male / female components. Let the car cool completely and then remove the air filter / PCM housing so you can reach the TC/ABS module. Remove and inspect, then reinstall the connector to be sure the connection is seated tight.

Other possibilities could be a damaged TC/ABS module if it was hit when the engine was reinstalled, or damaged wiring if something was overlooked during the removal /installation and the wires were pulled tight.

Keep us posted.