C107B

C107B-WHEEL SPEED COMPARATIVE PERFORMANCE





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
With the ignition on.

- Set Condition:
When one or more WSS reading is different from the readings received from the other WSS's. The Anti-Lock Brake Module compares WSS readings from side-to-side on an axle and front-to-rear above 40 km/h (25 mph).





Diagnostic Test

1. CHECK FOR DTC C107B-WHEEL SPEED COMPARATIVE PERFORMANCE
NOTE: This DTC must be active for the results of this test to be valid.

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

With the scan tool, read DTCs.

NOTE: The Anti-Lock Brake Module must sense ALL 4 wheels at 12 km/h (7.5 mph) before it will extinguish the ABS indicators.

Does the scan tool display: C107B-WHEEL SPEED COMPARATIVE PERFORMANCE?

Yes

- Go To 3


No

- Go To 2

2. CHECK WHEEL SPEED SENSOR SIGNALS
Turn the ignition on.
With the scan tool, monitor and graph ALL the WSS speeds and compare graph while an assistant drives the vehicle.
Slowly accelerate as straight as possible from a stop to 40 km/h (25 mph).
Is one or more WSS speeds showing 0 km/h (0 mph) or not matching other wheel speeds?

Yes

- Go To 3

No

- Perform the ABS Intermittent Condition diagnostic procedure.
- REFER TO the ABS-INTERMITTENT CONDITION TEST. ABS Intermittent Condition Test

3. CHECK FOR IMPROPER TIRE PRESSURE/MISMATCHED TIRES
Turn the ignition off.
Check and adjust the Tire pressure.
Check and adjust all other tire pressures.
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 WSS LOOSENESS, INSPECT SIGNAL SUPPLY CIRCUITS/CONNECTORS/TERMINALS FOR DAMAGE

NOTE: Check all terminals for broken, bent, pushed out, or corroded terminals.

Turn the ignition off.
Inspect the Anti-Lock Brake Module harness connector and each WSS harness connector that didn't match other wheel speeds for looseness and not properly fastened.
Inspect each WSS Signal and WSS Supply circuits between each WSS and Anti-Lock Brake Module for damage.
Is any WSS loose or any of the wiring/connectors/terminals damaged?

Yes

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

No

- Go To 5

5. CHECK EACH TONE WHEEL FOR DAMAGE
Turn the ignition off.
Inspect each Tone Wheel for damage, missing teeth, cracks, or looseness.

NOTE: The Tone Wheel teeth should be perfectly square, not bent, or nicked.

Is the Tone Wheels damaged?

Yes

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

No

- Replace the Anti-Lock Brake Module.
- PERFORM ABS VERIFICATION TEST. ABS Verification Test