Antilock Braking System (ABS)

Circuit Description

A DTC 38 relates to the BPMV seeing the signal from one sensor at more than double or less than half the frequency of the other sensors for a 12 second duration. This DTC also sets when all speed inputs differ more than eight percent. The vehicle speed must be over 12 mph for this DTC to set. Do not replace the BPMV for this DTC. A faulty BPMV will not cause this DTC to set.

Test Description

- Verify DTC 38 is stored in memory.
- Check speed sensor outputs using the Tech 1.
- Refer to "Erratic Sensor" chart 23, 27, 33, or 37. Antilock Braking System (ABS)

Diagnostic Aids

Do not replace the BPMV for this DTC. A faulty BPMV will not cause this DTC to set.

The following could set this DTC:

- Three or four significantly different size tires on the vehicle.
- Wrong VSS buffer (three sensor only) and different front wheel sizes.
- Wrong number of teeth on the exciter rings.