Diagnostic Test

With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.

1. With the scan tool, run a vehicle Scan Report, or record the Environmental Data related to the DTCs.
2. With the scan tool, erase all DTCs.
3. Turn the ignition off for a minimum of 10.0 seconds.
4. Start the engine.
5. Turn the Right Rear Vented Seat on.
6. With the scan tool, read CRSM DTCs.

Is the same DTC active?

Yes 

• Go To  2

No 

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

Does the (F918) Fused Ignition Circuit have an open 20A fuse?

Yes 

• Repair the Open Fuse.
• Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

No 

• Go To  3

1. The ignition must be off when checking a circuit for continuity to ground.
2. Isolate the circuit by disconnecting the Comfort Seat Rear Module (CRSM) and every component harness connector containing the circuit being tested. Note:  Use the appropriate SYSTEM 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:

   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 appropriate SYSTEM 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 BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

No 

• Go To  4

1. The ignition must be off when performing a resistance check to find a short between circuits.
2. Isolate the circuit by disconnecting the Comfort Seat Rear Module (CRSM) and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note:  Use the appropriate SYSTEM 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 CRSM harness connector.
4. With the other lead of the DVOM probe all other circuits at the CRSM harness connector.
   NOTE:

   With the circuit isolated there should be no continuity between the circuit being tested and any other circuit.

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 SYSTEM 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  5

1. Turn the ignition off.
2. Disconnect the harness connector at the component of the circuit being tested. Note:  Use the appropriate SYSTEM WIRING DIAGRAM as a guide to follow the path of the circuit.
3. Turn the ignition on.
4. Using a DVOM, measure the voltage of the circuit being tested at the component harness connector.

Is the voltage above 5.2 volts?

Yes 

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

No 

• Go To  6

1. The ignition must be off when performing a resistance check to find a short between circuits.
2. Isolate the circuit by disconnecting the Comfort Seat Rear Module (CRSM) and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note:  Use the appropriate SYSTEM 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 CRSM harness connector.
4. With the other lead of the DVOM probe all other circuits at the CRSM 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 SYSTEM 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  7

1. Reconnect all CRSM harness connectors.
2. Reconnect both vented seat motor harness connectors.
3. Start the engine.
4. Turn the Right Rear Vented Seat on.
5. Measure the voltage of the (P232) Right Rear Seat Vent Control circuit at each of the Right Rear Seat Cushion Vent Motor and Right Rear Seat Back Vent Motor harness connectors.
   NOTE:

   When probing a circuit at any harness connector, always use an appropriate back probing tool to prevent any possible damage to the terminals.

   Is the voltage below 0.75 volts at either measurement?

   Yes 

   • Replace the Right Rear Seat Vent Motors in accordance with the Service Information. Refer to MOTOR, VENTED REAR SEAT BACK, REMOVAL AND INSTALLATION or MOTOR, VENTED REAR SEAT CUSHION, REMOVAL AND INSTALLATION .
   • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

   No 

   • Go To  8

1. Disconnect all CRSM 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.
   • Check for spread terminals and verify proper terminal tension.

   Repair any conditions that are found.

5. Connect all CRSM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are 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 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. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.

    Did the DTC return?

    Yes 

    • Replace the Comfort Seat Rear Module in accordance with the Service Information.
    • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

    No 

    • Test complete. The wiring or poor connection problem has been repaired.
    • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .