Diagnostic Test

COMPARE WHEEL SPEED SENSOR SIGNALS
WARNING: Make sure brake capability is available before road testing.
1. With the scan tool, monitor ALL the WSS speeds while an assistant drives the vehicle.
2. Slowly accelerate as straight as possible from a stop to 40 km/h (25 mph).
  Does the Left Front WSS speed differ from the other WSS speeds by 8 km/h (5 mph) or show NO speed?
  
  Yes
  - Go to step 3
  No
  - Go to step 2
CHECKING INSIDE WHEEL SPEED
1. Slowly accelerate as straight as possible from a stop to 40 km/h (25 mph) and perform a 90 degree turn while monitoring if inside wheel is slower than outside.
  Was the inside wheel slower than outside?
  
  Yes
  - Perform the ABS-INTERMITTENT CONDITION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Go to step 3
INSPECT TONE WHEEL/BEARING
1. Turn the ignition off.
2. Visually inspect the tone wheel and bearing for damage.
  - Check the tone wheel teeth for missing teeth, cracks, and looseness. The teeth must be perfectly square, not bent, or nicked. Check the wheel bearing for worn/looseness.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Go to step 4
CHECK WHEEL SPEED SENSOR WIRING
1. Check the Anti-Lock Brakes Module and Wheel Speed Sensors harness connectors for incorrectly wired connectors.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Go to step 5
LEFT FRONT WHEEL SPEED SENSOR
1. Replace the Left Front Wheel Speed Sensor in accordance with the Service Information.
2. Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  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 ABS 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.
  
  Did DTC C1046-LEFT FRONT WHEEL PRESSURE PHASE MONITORING reset?
  
  Yes
  - Replace the Anti-Lock Brakes Module in accordance with the Service Information.
  - Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Test Complete.