Diagnostic Test

CHECK FOR AN ACTIVE DTC
NOTE:
Inspect the tires for improper air pressure and or mismatched tires before continuing, repair as necessary.
1. Perform any Service Bulletins that may apply.
2. Turn the ignition on.
3. With the scan tool, read ABS DTCs and record on the repair order.
4. With the scan tool, read and record Environmental Data to help identify the conditions in which the DTC was set.
5. With the scan tool, erase ABS DTCs.
  WARNING:
  To avoid possible serious or fatal injury, check brake capability is available before road testing.
  
  NOTE:
  Vehicle must be driven for several minutes above 15 km/h (9 mph) for set conditions to be met.
6. Test drive the vehicle straight with speeds above 15 km/h (9 mph).
7. With the scan tool, read ABS DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - Perform the ABS-INTERMITTENT CONDITION TEST. Refer to ABS INTERMITTENT CONDITION .
CHECK WHEEL SPEED SENSOR SIGNALS
1. Turn the ignition on.
2. With the scan tool, monitor and graph ALL the Wheel Speed Sensors speeds and compare.
3. Slowly accelerate as straight as possible from a stop to 15 km/h (9 mph).
  Is one or more of the WSS speeds showing 0 km/h (0 mph) or not matching the other WSS speeds?
  
  Yes
  - Go To 3
  No
  - Perform the ABS-INTERMITTENT CONDITION TEST. Refer to ABS INTERMITTENT CONDITION .
INSPECT WHEEL SPEED SENSOR (WSS) FOR DAMAGE
NOTE:
Check all terminals for broken, bent, pushed out, or corroded terminals.
1. Turn the ignition off.
2. Inspect each WSS for looseness and or not properly fastened.
  Are any WSS loose or any of the wiring/connectors/terminals damaged?
  
  Yes
  - Repair as necessary.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Go To 4
CHECK EACH HUB AND WHEEL BEARING FOR DAMAGE
1. Turn the ignition off.
2. Inspect each Hub and Wheel Bearing for damage, corrosion, cracks, looseness, or improper installation.
  Are any of the Hub and or Wheel Bearings damaged?
  
  Yes
  - Replace the Hub and Wheel Bearing in accordance with the Service Information.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Go To 5
WHEEL SPEED SENSOR (WSS)
1. Replace the Wheel Speed Sensor in accordance with the Service Information. or. Refer to SENSOR, WHEEL SPEED, FRONT, REMOVAL AND INSTALLATION . Refer to SENSOR, WHEEL SPEED, REAR, REMOVAL AND INSTALLATION .
2. Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
3. With the scan tool, monitor and graph ALL the Wheel Speed Sensors speeds and compare.
4. Slowly accelerate as straight as possible from a stop to 15 km/h (9 mph).
5. With the scan tool, read ABS DTCs.
  Does this DTC remain active?
  
  Yes
  - Go To 6
  No
  - Test complete.
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect the ABS Module harness connector.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Perform a terminal drag test on each connector terminal to verify proper terminal tension.
  Repair any conditions that are found.
5. Connect the ABS Module harness connector. Be certain that the harness connector is fully seated and the connector lock is fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect the related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase ABS DTCs.
  WARNING:
  To avoid possible serious or fatal injury, check brake capability is available before road testing.
9. Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
10. With the scan tool, read ABS Module DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Anti-lock Brake System (ABS) Module in accordance with the Service Information. Refer to MODULE, ANTI-LOCK BRAKE SYSTEM (ABS), REMOVAL AND INSTALLATION .
  - Perform ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Perform ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  - Test complete.