C0029

ABS/RF & LF Wheel Speed Sensors Circuit Schematic:

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
^ Electronic Brake Control Module (EBCM) losing both front wheel speed signals when the vehicle is at speeds over19 km/h (12 mph) (brake released) or 32 km/h (20 mph) (brake applied).

ACTION TAKEN WHEN THE DTC SETS
^ ANTILOCK indicator lamp is illuminated
^ ABS is disabled

NOTE: Diagnostic Trouble Code (DTC) C0029 is an 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).

CONDITIONS FOR CLEARING THE DTC
^ Conditions for setting the DTC are repaired and the Scan Tool clear (DTCs) function is used.

DTC C0029 Simultaneous Drop-Out Of Front Wheel Speed Signals:

DIAGNOSTIC AIDS
The 5-way harness connector or the EBCM are the most probable causes for this DTC. An intermittent malfunction may be caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation. Any circuitry that is suspected of causing the intermittent complaint should be thoroughly checked for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wiring connections or physical damage to the wiring harness.

DTC C0029 Simultaneous Drop-Out Of Front Wheel Speed Signals:

TEST DESCRIPTION
The numbers below refer to the step numbers on the chart.
[3] Checks the Resistance of the wheel speed sensor circuit.
[4] Checks the Resistance of the wheel speed sensor circuit.