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Discussion Starter #1
Service Traction System alert and ABS light came on only after car began to move. Ultimately I had to replace a hub -- problem solved.

Initially, however, I wasted time doing DC tests, not realizing that the STS/ABS light will come on immediately upon starting up if there is a DC connectivity problem (unless the control module is bad). If the warning lights come on only after the car moves (**not while turning the steering wheel**), this means the AC signal from the wheel speed sensor is either not being generated by the sensor (most likely), or the EBCM is failing to sense the AC signal but is successfully sensing DC upon startup (unlikely). If the light comes on only when turning the steering wheel, it is again likely a DC connectivity problem.

Do the STS alert and ABS light illuminate immediately when the car is turned on or only after the car begins to move?
1. Immediately when car is turned on: Most likely a connection problem. Test the harness for short/open and the wheel speed sensor resistance (should show ~1100 ohms). In the less likely event all DC tests check out, you may have a bad EBCM.
2. Only after movement: If fault occurs only when turning the steering wheel, go to #1. If not steering related, it is most likely that the sensor at the hub has gone bad. Have auto parts store read ABS codes with a scanner to find which wheel is causing the fault, and replace the hub.
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