A035

Diagnostic Chart:

Wiring 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 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.

FAILURE CONDITION
DTC A035 can be set anytime after initialization. If either of the right rear wheel speed circuits are shorted to voltage or ground, a malfunction exists.

ACTION TAKEN
A malfunction DTC is stored, ABS is disabled and the ABS indicator lamp is turned "ON."

TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This helps to identify whether the DTC is due to a short to battery or short to ground.
2. This insures that the wheel speed sensor is not shorted to ground.
3. This step checks to see if wheel speed sensor circuitry is shorted to voltage.
4. This insures that the wheel speed sensor circuitry has good continuity.
5. This checks for short to ground in wheel speed sensor wiring.
6. This checks for short to voltage in wheel speed sensor wiring.
7. This step checks for a possible intermittent malfunction.

DIAGNOSTIC AIDS
An "Intermittent" malfunction may be caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation.

The frequency of the malfunction can be checked by using the enhanced diagnostic function of the Tech 1.

If the customers comments reflect that the ABS indicator lamp is "ON" only during moist environmental changes (rain, snow, vehicle wash), all wheel speed sensor circuitry should be thoroughly inspected for signs of water intrusion. If DTC is not current, clear DTCs and simulate the effects of water intrusion. Use the following procedure. Spray down the suspected area with a 5% salt water solution (two teaspoons of salt to 12 oz. of water). Start vehicle, allow vehicle to run for 10 seconds. If DTC returns immediately, replace suspected harness.

Any circuitry, that is suspected as 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.

When replacing a wheel speed sensor, inspect the sensor terminals and harness connector for corrosion and/or water intrusion. If evidence of corrosion or water intrusion exists, replace wheel speed sensor harness.