Diagnostic Test

1. Verify the Park Assist Sensor is not damaged and properly connected before proceeding with this diagnostic procedure.
2. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
3. With the scan tool, run a vehicle Scan Report, or record the Environmental Data related to the DTCs.
4. With the scan tool, erase all DTCs.
5. Turn the ignition off for a minimum of 10.0 seconds.
6. Turn the ignition on.
7. Using the recorded Environmental Data and the When Monitored Conditions above, operate the vehicle in the conditions that set the DTC.
8. With the scan tool, read DTCs.

Did the DTC return?

Yes 

• Go To  2

No 

• Perform the appropriate INTERMITTENT CONDITION diagnostic procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .

1. The ignition must be off when checking for a short between circuits.
2. Isolate the circuit by disconnecting the ECU and every component harness connector containing the circuit being tested. Note:  Use the appropriate wiring diagram as a guide to follow the path of the circuit.
3. Connect the test leads of the DVOM and check for continuity between the circuits being tested at the component harness connector.

Is there continuity between the circuits?

Yes 

• Repair the short between the circuits.
• Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

No 

• Go To  3

1. The ignition must be off when performing a resistance check to find a short between circuits.
2. Isolate the circuit by disconnecting the ECU and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note: Use the appropriate wiring diagram as a guide to follow the path of the circuit.
3. Connect one lead of the DVOM to the circuit being tested at the ECU harness connector.
4. With the other lead of the DVOM probe all other circuits at the ECU harness connector.

Is there continuity between the circuit being tested and any other circuit?

Yes 

• Repair the short between the circuits that have continuity. Use the appropriate wiring diagram as a guide to trace the circuits and look for any in-line connectors to help isolate the location of the short.
• Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

No 

• Go To  4

1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the ECU and the component harness connector containing the circuit being tested. Note:  Use the appropriate wiring diagram as a guide to follow the path of the circuit.
3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note:  The meter leads can add resistance to the measurement value.
4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
5. Connect the other lead to the circuit being tested at the ECU harness connector and measure the resistance of the circuit.

Is the resistance below 3.0 Ohms?

Yes 

• Go To  5

No 

• Repair the circuit for an open or high resistance.
• Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

1. The ECU harness connectors must be connected to the ECU during this test step.
2. Disconnect the sensor harness connector.
3. With the ignition in the off position, connect a fused jumper between the sensor signal circuit and the sensor ground circuit at the sensor harness connector.
4. Turn the ignition on.
5. With the scan tool, read DTCs.

Does the scan tool display the DTC B128F-11 with the jumper in place?

Yes 

• Replace the Park Assist Sensor in accordance with the Service information. Refer to SENSOR, PARK ASSIST, REMOVAL AND INSTALLATION .
• Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

No 

• Go To  6

1. Disconnect all PAM harness connectors.
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. Reconnect all PAM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all 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 DTCs.
9. Using the recorded 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 PAM DTCs.

    Did the DTC return?

    Yes 

    • Replace the PAM in accordance with the Service information. Refer to MODULE, PARK ASSIST (PAM), REMOVAL AND INSTALLATION .
    • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

    No 

    • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
    • Test complete.