Diagnostic Test

Read the HIGH-VOLTAGE SAFETY PROCEDURES. Refer to  HIGH VOLTAGE SAFETY PROCEDURES  . 

When the HIGH-VOLTAGE POWER-DOWN PROCEDURE is necessary. Refer to  VEHICLE HIGH VOLTAGE POWER DOWN  . 

1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. For future reference, with the scan tool, 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 10.0 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 appropriate INTERMITTENT CONDITION diagnostic procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .

1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note:  Use the 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.
   NOTE:

   When probing a circuit at an Electronic Control Unit (ECU) harness connector, always use an appropriate back probing tool to prevent any possible damage to the ECU terminals. 

   Is the resistance below 3.0 Ohms?

   Yes 

   • Go To  3

   No 

   • Repair the circuit for an open or high resistance.
   • Perform the Electric Vehicle Control Unit (EVCU) VERIFICATION TEST. Refer to ELECTRIC VEHICLE CONTROL UNIT (EVCU) VERIFICATION TEST .

1. The ignition must be off when checking a circuit for continuity to ground.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Connect the negative lead of the DVOM to a known good ground.
4. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.
   NOTE:

   When probing a circuit at an Electronic Control Unit (ECU) harness connector, always use an appropriate back probing tool to prevent any possible damage to the ECU terminals. 

   NOTE:

   There should be no continuity between ground and the circuit being tested. 

   Is there continuity between ground and the circuit being tested?

   Yes 

   • Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
   • Perform the Electric Vehicle Control Unit (EVCU) VERIFICATION TEST. Refer to ELECTRIC VEHICLE CONTROL UNIT (EVCU) VERIFICATION TEST .

   No 

   • Go To  4

1. Replace the component in accordance with the Service Information. Refer to VALVE, A/C EXPANSION, REMOVAL AND INSTALLATION .
2. Connect the component and Electronic Control Unit (ECU) harness connectors.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Using the Environmental Data or When Monitored Conditions above, operate the vehicle within the conditions that set the DTC.
6. With the scan tool, read DTCs.

   Did the DTC return?

   Yes 

   • Go To  5

   No 

   • Replacing the faulty component repaired the fault.
   • Perform the Electric Vehicle Control Unit (EVCU) VERIFICATION TEST. Refer to ELECTRIC VEHICLE CONTROL UNIT (EVCU) VERIFICATION TEST .

1. Disconnect all PIM 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 PIM 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 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 HCP DTCs.

    Did the DTC return?

    Yes 

    • Replace the Electric Vehicle Control Unit (EVCU) in accordance with the Service information. Refer to ELECTRIC VEHICLE CONTROL UNIT (EVCU) .
    • Perform the Electric Vehicle Control Unit (EVCU) VERIFICATION TEST. Refer to ELECTRIC VEHICLE CONTROL UNIT (EVCU) VERIFICATION TEST .

    No 

    • Perform the Electric Vehicle Control Unit (EVCU) VERIFICATION TEST. Refer to ELECTRIC VEHICLE CONTROL UNIT (EVCU) VERIFICATION TEST .
    • Test complete.