Diagnostic Test

1. With the scan tool, read Electronic Shift Module (ESM) DTCs and record on the repair order.
2. Record the Event Data and Environmental Data.
3. With the scan tool, erase DTCs.
4. 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.
5. With the scan tool, read ESM DTCs.

   Did the DTC return?

   Yes 

   • Go To  2

   No 

   • Go To  7

1. Turn the ignition off.
2. Disconnect the ESM harness connector.
3. Turn the ignition on.
4. Measure the voltage between ground and the CAN EPT (+) circuit at the ESM harness connector.
5. Measure the voltage between ground and the CAN EPT (-) circuit at the ESM harness connector.

   Is the voltage between 2.4 and 2.6 volts for each circuit?

   Yes 

   • Using the schematics as a guide, check the Electronic Shift Module (ESM) connector and all related in-line connector terminals for corrosion, damage, or pushed out terminals. Pay particular attention to the power and ground circuits. If no problems are found, replace the ESM in accordance with the Service Information. Refer to MODULE, ELECTRONIC SHIFT (ESM), REMOVAL AND INSTALLATION .
   • Perform the ESM VERIFICATION TEST. Refer to ESM VERIFICATION TEST  .

   No 

   • Go To  3

1. Turn the ignition off.
2. Disconnect the Power Inverter Module (HCP/PIM) harness connector.
3. Measure the resistance of the CAN EPT (+) circuit between the ESM harness connector and the (HCP/PIM) harness connector.
4. Measure the resistance of the CAN EPT (-) circuit between the ESM harness connector and the (HCP/PIM) harness connector.

   Is the resistance below 3.0 Ohms for each circuit?

   Yes 

   • Go To  4

   No 

   • Repair the affected CAN EPT circuit(s) for an open or high resistance.
   • Perform the ESM VERIFICATION TEST. Refer to ESM VERIFICATION TEST  .

1. Check for continuity between ground and the CAN EPT (+) circuit at the (HCP/PIM) harness connector.
2. Check for continuity between ground and the CAN EPT (-) circuit at the (HCP/PIM) harness connector.

   Is there continuity between ground and the either of the CAN EPT circuits?

   Yes 

   • Repair the affected CAN EPT circuit(s) for a short to ground.
   • Perform the ESM VERIFICATION TEST. Refer to ESM VERIFICATION TEST  .

   No 

   • Go To  5

1. Check for continuity between the CAN EPT (+) circuit and all other circuits at the (HCP/PIM) harness connector.
2. Check for continuity between the CAN EPT (-) circuit and all other circuits at the (HCP/PIM) harness connector.

   Is there continuity between either CAN EPT circuit and any other circuit?

   Yes 

   • Repair the affected CAN EPT circuit(s) for a short to another circuit.
   • Perform the ESM VERIFICATION TEST. Refer to ESM VERIFICATION TEST  .

   No 

   • Using the schematics as a guide, check the Electronic Shift Module (ESM) connector and all related in-line connector terminals for corrosion, damage, or pushed out terminals. Pay particular attention to the power and ground circuits. If no problems are found, replace the ESM in accordance with the Service Information. Refer to MODULE, ELECTRONIC SHIFT (ESM), REMOVAL AND INSTALLATION .
   • Perform the ESM VERIFICATION TEST. Refer to ESM VERIFICATION TEST  .

Yes 

• Replace the HCP (PIM) in accordance with the Service Information.

  Refer to MODULE, POWER INVERTER (PIM), REMOVAL AND INSTALLATION .

• Perform the ESM VERIFICATION TEST. Refer to ESM VERIFICATION TEST  .

1. The conditions necessary to set the DTC are not present at this time.
2. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
3. Wiggle the wires while checking for shorted and open circuits.
4. Check for any Service Bulletins that may apply.

   Were any problems found?

   Yes 

   • Repair as necessary.
   • Perform the ESM VERIFICATION TEST. Refer to ESM VERIFICATION TEST  .

   No 

   • Test complete.