Diagnostic Test

READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN
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 INTERMITTENT CONDITION diagnostic procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK THE COMFORT SEAT MODULE (CSM) STATUS ON THE BUS
NOTE:
NO HVAC mode or temp functions will perform as desired unless auto-addressing was successful.

NOTE:
NO Heated/Vented Seats functions will operate unless auto-addressing was successful.

NOTE:
Auto-addressing needs to be done every time a CSM/CSWSM/CRSM or an Actuator is replaced.

Turn the ignition on.
1. With the scan tool, read the topology on the Vehicle View screen.
  Does the Vehicle View screen indicate that the Module is active on the bus?
  
  Yes
  - Go To 3
  No
  - Perform the Communication Diagnostic Procedure Test. Refer to COMMUNICATION DIAGNOSTIC PROCEDURE .
ISOLATE AND CHECK THE (P841) FRONT LEFT SEAT CUSHION HEATER FEED CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the Comfort Seat Module (CSM) and the component harness connector containing the circuit being tested. Note: Use the appropriate wiring information 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 and measure the resistance of the circuit.
Is the resistance below 2.0 Ohms?

Yes
- Go To 4
No
- Repair the circuit for an open or high resistance.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
ISOLATE AND CHECK THE (P841) FRONT LEFT SEAT CUSHION HEATER FEED CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT AT THE COMFORT SEAT MODULE HARNESS CONNECTOR
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 Module (CSM) and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note: Use the appropriate wiring information 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.
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 wiring information 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
REPLACE THE FRONT LEFT SEAT CUSHION HEATER ELEMENT RETEST FOR DTCS
1. Turn the ignition off.
2. Replace the component in accordance with the Service Information.
3. Connect the component and Comfort Seat Module (CSM) harness connectors.
4. Turn the ignition on.
5. With the scan tool, erase all DTCs.
6. Turn the ignition off for a minimum of 10.0 seconds.
7. Turn the ignition on.
8. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
9. With the scan tool, read DTCs.
Did the DTC return?

Yes
- Go To 6
No
- Replacing the faulty component repaired the fault.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all CSM 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 CSM 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 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 .