Diagnostic Test

WARNING: This page is about a different variant/trim than selected.

READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN
1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. For future reference, run and save a vehicle Scan Report and all related recorded data.
3. With the scan tool, erase all DTCs.
4. Turn the ignition off for a minimum of 75.0 seconds.
5. Turn the ignition on.
6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT DTC .
CHECK FOR OTHER DTCS
1. Refer to the recorded DTCs.
  Are DTCs P258A-00, P258C-00 or P258D-00 active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to DTC INDEX (1 OF 2) and/or DTC INDEX (2 OF 2) .
  No
  - Go To 3
CHECK THE ELECTRIC VACUUM PUMP (EVP) OPERATION
NOTE:
If the scan too does not have the actuator function, it may be necessary to use a fused jumper wire at the relay to activate the Electronic Vacuum Pump (EVP).
1. Turn the ignition on.
2. With the scan tool actuate the Electronic Vacuum Pump (EVP).
  Does the EVP run?
  
  Yes
  - Go To 10
  No
  - Go To 4
CHECK THE VACUUM PUMP RELAY (T110) CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Using a 12-Volt test light connected to 12 Volts, back probe the Vacuum Pump Relay (T110) Control circuit at the PDC C3 harness connector.
3. Ignition on, engine not running.
4. With the scan tool actuate the Electronic Vacuum Pump (EVP).
  Does the test light illuminate brightly?
  
  Yes
  - Go To 6
  No
  - Go To 5
CHECK THE VACUUM PUMP RELAY (T110) CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the PDC C3 harness connector.
3. Disconnect the PCM C1 harness connector.
4. Measure the resistance of the Vacuum Pump Relay (T110) Control circuit between the PDC C3 harness connector and the PCM C1 harness connector.
  Is the resistance less than 3.0 Ohms?
  
  Yes
  - Go To 6
  No
  - Repair the Vacuum Pump Relay (T110) Control circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK THE VACUUM PUMP RELAY (T108) OUTPUT CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Reconnect the PDC C3 harness connector (if it was previously disconnected).
3. Reconnect the PCM C1 harness connector (if it was previously disconnected).
4. Using a 12-Volt test light connected to ground, back probe the Vacuum Pump Relay (T108) Output circuit at the PDC C3 harness connector.
5. Ignition on, engine not running.
6. With the scan tool actuate the EVP.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 7
  No
  - Go To 9
CHECK THE VACUUM PUMP RELAY (T108) OUTPUT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the PDC C3 harness connector.
3. Disconnect the PCM C1 harness connector.
4. Measure the resistance of the Vacuum Pump Relay (T108) Output circuit between the PDC C3 harness connector and the PCM C1 harness connector.
  Is the resistance less than 3.0 Ohms?
  
  Yes
  - Go To 8
  No
  - Repair the Vacuum Pump Relay (T108) Output circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK THE (Z908) EVP GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Using a 12-volt test light connected to 12 Volts, probe the (Z908) EVP Ground circuit at the EVP harness connector.
  Does the test light illuminate brightly?
  
  Yes
  - Replace the Electric Vacuum Pump (EVP) in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
  No
  - Repair the (Z908) EVP Ground circuit for an open/high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK THE PDC FOR PROPER OPERATION
1. Check Fuse 74 (20A) on the PDC for an open.
  Is the fuse open?
  
  Yes
  - Replace Fuse 74 (20A) and determine what caused the short circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
  No
  - Replace the Power Distribution Center (PDC) in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK FOR PINCHED VACUUM SUPPLY LINE
1. Turn the ignition off.
2. Check the vacuum supply line to brake booster for a pinched, cut or open hose.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
  No
  - Go To 11
CHECK THE VACUUM PRESSURE SIGNAL ON THE SCAN TOOL
1. Start the engine.
2. With the scan tool, view and record the vacuum pressure signal with foot off the brake pedal.
3. With the scan tool, view the vacuum pressure signal while pressing the brake pedal several times.
4. Record the highest value.
  Without the brake pedal applied, was the vacuum pressure signal -40 kpa (12 in. Hg)?
  
  Yes
  - Go To 12
  No
  - Replace the Power Brake Booster in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK FOR VACUUM PRESSURE SIGNAL CHANGE ON THE SCAN TOOL
1. Turn the ignition on.
2. Remove the Vacuum Pressure Sensor from the Booster.
3. Connect a vacuum pump to the Vacuum Pressure Sensor.
4. Apply vacuum to the Vacuum Pressure Sensor and watch for signal change.
  Is the voltage signal changing on the scan tool as vacuum is being applied?
  
  Yes
  - Go To 13
  No
  - Replace the Vacuum Pressure Sensor in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK BRAKE BOOSTER CHECK VALVE
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 14
  No
  - Replace the Power Brake Booster Check Valve in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK THE POWER BRAKE BOOSTER OPERATION
1. Reinstall the Brake Booster Check Valve.
2. Apply vacuum to the Brake Booster.
  Is the Power Brake Booster holding vacuum?
  
  Yes
  - Go To 15
  No
  - Replace the Power Brake Booster in accordance with the Service information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK THE ANTI-LOCK BRAKE SYSTEM (ABS) MODULE OPERATION AND ANY RELATED CONNECTORS
1. Turn the ignition off to the lock position.
2. Perform any Technical Service Bulletins that may apply.
3. Inspect the related wiring harness. Look for any chafed, pierced, pinched or partially broken wires.
4. Inspect the related wire harness connectors. Look for broken, bent, pushed out or corroded terminals.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
  No
  - Replace the Anti-lock Brake System (ABS) Module in accordance with the Service Information.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .