Diagnostic Test

CHECK FOR AN ACTIVE DTC
NOTE:
This DTC must be active for the results of this test to be valid.
1. Perform any Service Bulletins that may apply.
2. Turn the ignition on.
3. With the scan tool, read DTCs and record on the vehicle 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.
6. Start the vehicle.
7. Press and release the brake pedal.
8. With the scan tool, read ABS DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - The condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires.
  - Perform the ABS-INTERMITTENT CONDITION TEST. Refer to ABS INTERMITTENT CONDITION .
CHECK FOR POWERTRAIN CONTROL MODULE (PCM) OR COMMUNICATION RELATED DTCS
1. Refer to the recorded DTCs.
  Are there any PCM or Communication related DTCs active?
  
  Yes
  - Perform the appropriate diagnostic procedures before continuing with this test. Refer to 3.6L - DIAGNOSTIC CODE INDEX .
  No
  - Go To 3
CHECK THE VACUUM PRESSURE SIGNAL
1. Start the engine.
2. With the scan tool, in the Powertrain Control Module (PCM) under "Data Display" view and record the "Brake Booster Pressure" signal with no brake applied.
3. Turn the engine off.
4. Turn the ignition on.
5. With the scan tool, under "Data Display" view the "Brake Booster Pressure" signal with no brake applied.
  Is the vacuum pressure signal staying consistent?
  
  Yes
  - Go To 4
  No
  - Go To 5
CHECK FOR A VACUUM PRESSURE SIGNAL CHANGE
1. Turn the ignition on.
2. Remove the Vacuum Pressure Sensor from the Brake Booster.
3. Connect a vacuum pump to the Vacuum Pressure Sensor.
4. Apply vacuum to the Vacuum Pressure Sensor.
5. With the scan tool, under "Data Display" view the vacuum pressure and watch for signal change.
  Is the vacuum pressure signal changing on the scan tool as vacuum is being applied?
  
  Yes
  - Go To 7
  No
  - Replace the Vacuum Pressure Sensor.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
CHECK THE BRAKE BOOSTER CHECK VALVE FOR CORRECT OPERATION
1. Remove the Brake Booster Check Valve.
2. Apply vacuum to the booster side of the check valve.
  Is the Brake Booster Check Valve holding vacuum?
  
  Yes
  - Go To 6
  No
  - Replace the Brake Booster Check Valve.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
CHECK THE POWER BRAKE BOOSTER FOR CORRECT OPERATION
1. Install the Brake Booster Check Valve.
2. Connect a vacuum pump to the Brake Booster Check Valve.
3. Using the vacuum pump, apply vacuum to the Brake Booster.
  Is the Power Brake Booster holding vacuum?
  
  Yes
  - Go To 8
  No
  - Replace the Power Brake Booster in accordance with the Service Information. Refer to BOOSTER, POWER BRAKE, REMOVAL .
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
REPLACE THE VACUUM PRESSURE SENSOR AND TEST FOR DTCS
1. Turn the ignition off.
2. Replace the Vacuum Pressure Sensor.
3. Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
4. With the scan tool, read the DTCs.
  Does the DTC remain active?
  
  Yes
  - Go To 8
  No
  - Test complete, the condition or conditions that originally set this DTC are not present at this time.
PERFORM THE ABS INITIALIZATION ROUTINE
1. Park the vehicle on level ground.
2. Turn the ignition on.
3. With the scan tool, under "Miscellaneous Functions" perform the ABS Initialization routine.
4. Perform ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  Was the ABS Initialization routine successful?
  
  Yes
  - Test complete.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Perform the ABS Initialization routine again, if still unsuccessful.
  - Go To 9
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 .
  - Perform ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Perform ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  - Test complete.