C0030

C0030-29-LEFT FRONT TONE WHEEL - INVALID SIGNAL

For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
With the ignition on and no overvoltage or undervoltage is present.

- Set Condition:
When the Anti-Lock Brake Module detects periodic drops of a WSS signal.





NOTE: If DTC C0030-01 is present it must be repaired before continuing with this diagnostic procedure.

1. VERIFY THE DTC IS ACTIVE

NOTE: This DTC must be active for the results of this test to be valid.

1. Turn the ignition on.
2. With the scan tool, record and erase DTCs.

CAUTION: Make sure brake capability is available before road testing.

3. Road test the vehicle over 40 km/h (25 mph).

NOTE: Vehicle must be driven above 40 km/h (25 mph) for set conditions to be met.

4. With the scan tool, read DTCs.

Is the DTC active at this time?

Yes

- Go To 2

No

- Perform ABS INTERMITTENT CONDITION diagnostic procedure, ABS Intermittent Condition Test.

2. CHECK WHEEL SPEED SENSOR SIGNALS
1. Turn the ignition on.
2. With the scan tool, monitor and graph ALL the WSS speeds and compare graph while an assistant drives the vehicle.

NOTE: If graph shows periodic dropouts pay close attention to the tone wheel.

3. Slowly accelerate as straight as possible from a stop to 40 km/h (25 mph).

Is the Left Front WSS speed showing 0 km/h (0 mph) or not matching other wheels or showing erratic behavior?

Yes

- Go To 3

No

- Perform ABS INTERMITTENT CONDITION diagnostic procedure, ABS Intermittent Condition Test.

3. CHECK FOR IMPROPER TIRE PRESSURE/MISMATCHED TIRES
1. Turn the ignition off.
2. Check and adjust the Left Front Tire pressure.
3. Check and adjust all other tire pressures.
4. Inspect for mismatched tires on vehicle.

Is the tire improperly inflated or mismatched tires on vehicle?

Yes

- Repair as necessary.
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Go To 4

4. CHECK LEFT FRONT WHEEL BEARING FOR DAMAGE
1. Inspect the Left Front wheel bearing for excessive runout or clearance.

NOTE: Refer to the appropriate service information, if necessary, for procedures or specifications.

Is the Left Front Wheel Bearing Damaged?

Yes

- Repair as necessary.
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Go To 5

5. LEFT FRONT WHEEL SPEED SENSOR
1. Replace the Left Front Wheel Speed Sensor. Front.
2. Perform ABS VERIFICATION TEST ABS Verification Test.

CAUTION: Make sure brake capability is available before road testing.

3. Road test the vehicle over 40 km/h (25 mph).

NOTE: Vehicle must be driven above 40 km/h (25 mph) for set conditions to be met.

4. With the scan tool, read the ABS DTCs.

Does the DTC remain active?

Yes

- Replace the Anti-Lock Brakes Module. Anti-Lock Brake System Module - Removal
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Test Complete.