C0038
DTC C0038 Circuit Diagram:
CIRCUIT DESCRIPTION
As a toothed ring passes by the wheel speed sensor, changes in the electromagnetic field cause the wheel speed sensor to produce a sinusoidal (AC) voltage signal whose frequency and amplitude is proportional to wheel speed. The magnitude of this signal is directly related to wheel speed and the proximity of the wheel speed sensor to the toothed ring, often referred to as the air gap.
CONDITIONS FOR SETTING DTC
- Vehicle speed greater than 12 mph.
- No unexpected wheel acceleration, or anything that generates consistent differences between wheel speed signals.
AND any of the following
- Any wheel speed differing from the vehicle speed for any of the following:
- One mismatched wheel speed more than double or less than half the other 3 wheel speeds.
- All four wheel speeds differing from each other by 8 percent.
ACTION TAKEN WHEN DTC IS SET
- ANTILOCK indicator lamp is illuminated
- Antilock Brake System (ABS) is disabled
NOTE: This DTC is a Ignition Latched DTC which indicates the above is true until the ignition is turned to OFF (even if the cause of the DTC is intermittent).
DIAGNOSTIC AIDS
A DTC C0038 is usually set by significantly different tires installed on the vehicle.
DTC CHART TEST DESCRIPTION
DTC C0038 Diagnostic Chart:
NOTE: Number(s) below refer to number(s) on the diagnostic chart.
2. Check all speed sensor outputs using the scan tool.