Diagnostic Test

WARNING: This page is about a different car, the 2015 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.

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. Turn the left rear heated seat on and operate in all modes.
6. With the scan tool, read HSM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Go To 5
CHECK THE LEFT REAR SEAT CUSHION HEATER ELEMENT RESISTANCE
1. Turn the ignition off.
2. Disconnect the Left Rear Seat Cushion Heater harness connector.
3. Measure the resistance between the (P177) Left Rear Seat Heater Control circuit and the (Z922) Ground circuit at the Left Rear Seat Cushion Heater harness connector (seat side).
  Is the resistance above 4.8 Ohms?
  
  Yes
  - Replace the Rear Seat Cushion Heater Element in accordance with the Service Information. Refer to PAD, HEATER, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Go To 3
CHECK (P177) LEFT REAR SEAT HEATER CONTROL CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Disconnect the HSM C3 harness connector.
2. Measure the resistance of the (P177) Left Rear Seat Heater Control circuit between the HSM C3 harness connector and the Left Rear Seat Cushion Heater harness connector (harness side).
  Is the resistance below 1.0 Ohm?
  
  Yes
  - Go To 4
  No
  - Repair the (P177) Left Rear Seat Heater Control circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK (Z922) GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. With a 12-volt test light connected to 12 volts, check the (Z922) Ground circuit at the Left Rear Seat Cushion Heater harness connector (harness side).
  NOTE:
  The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
  
  Does the test light illuminate brightly?
  
  Yes
  - Replace the Heated Seat Module (HSM) in accordance with the Service Information. Refer to MODULE, HEATED SEAT, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Repair the (Z922) Ground circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE WIRING AND CONNECTORS
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. Wiggle the wiring and connectors while checking for shorted and open circuits.
3. Check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
4. Check for any Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Test complete.