Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read Heated Seat Module (HSM) DTCs and record on the repair order.
2. With the scan tool, erase HSM DTCs.
3. Turn the ignition off.
4. Start the Engine.
5. With the scan tool, read HSM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK THE (P921) LEFT SEAT VENT RETURN CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the HSM C5 harness connector.
3. Start the Engine.
4. Measure the voltage between ground and the (P921) Left Seat Vent Return circuit at the HSM C5 harness connector.
  Is the voltage 5.0 volts or above?
  
  Yes
  - Go To 3
  No
  - Go To 5
CHECK THE LEFT SEAT CUSHION VENT MOTOR
1. Turn the ignition off.
2. Disconnect the Left Seat Cushion Vent Motor harness connector.
3. Start the Engine.
4. Measure the voltage between ground and the (P921) Left Seat Vent Return circuit at the HSM C5 harness connector.
  Is the voltage 5.0 volts or above?
  
  Yes
  - Go To 4
  No
  - Replace the Left Seat Cushion Vent Motor in accordance with the Service Information. Refer to MOTOR, VENTED SEAT, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE LEFT SEAT BACK VENT MOTOR
1. Turn the ignition off.
2. Disconnect the Left Seat Back Vent Motor harness connector.
3. Start the Engine.
4. Measure the voltage between ground and the (P921) Left Seat Vent Return circuit at the HSM C5 harness connector.
  Is there any voltage present?
  
  Yes
  - Repair the (P921) Left Seat Vent Return circuit for a short to voltage.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Replace the Left Seat Back Vent Motor in accordance with the Service Information. Refer to MOTOR, VENTED SEAT, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all HSM 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 HSM 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 HSM DTCs.
  Is the same DTC active?
  
  Yes
  - Replace the Heated Seat Module (HSM) in accordance with the Service Information. Refer to MODULE, HEATED SEAT (HSM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Repairing the wiring harness or connections corrected the problem.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .