Diagnostic Test

WARNING: This page is about a different car, the 2013 RAM 3500 HD and 2013 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

CHECK IF THE DTC IS ACTIVE
NOTE:
Make sure the battery is fully charged and the charging system is operating properly before proceeding.
1. Turn the ignition on.
2. Using a scan tool, record and erase Diagnostic Trouble Codes (DTCs).
  NOTE:
  It is recommended to record any Environmental Data to help identify the conditions in which the DTC was set.
3. Turn the ignition off.
4. Ignition on, engine running.
5. Turn the Heated Seat on and operate in all modes.
6. With the scan tool, read Heated Seat Module (HSM) DTCs.
  Does the scan tool show this DTC as active?
  
  Yes
  - Go To 2
  No
  - Go To 6
CHECK THE (P187) LEFT FRONT SEAT HEATER CONTROL CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the Left Seat Cushion Heater harness connector.
3. Disconnect the Left Seat Back Heater harness connector.
  NOTE:
  Check connectors - Clean/repair as necessary.
4. Ignition on, engine running.
5. With the scan tool, actuate the seat heaters on high.
6. Using a 12-volt test light connected to ground, check the (P187) Left Front Seat Heater Control circuit at the Left Seat Cushion and Left Seat Back Heater harness connectors (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 at both connectors?
  
  Yes
  - Go To 3
  No
  - Repair the (P187) Left Front Seat Heater Control circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE (Z909) GROUND CIRCUIT FOR AN OPEN
1. With the scan tool, turn off the seat heater actuator.
2. Turn the ignition off.
3. Using a 12-volt test light connected to 12-volts, check the (Z909) Ground circuit at the Left Seat Cushion and Left Seat Back Heater harness connectors (harness side).
  Does the test light illuminate brightly at both connectors?
  
  Yes
  - Go To 4
  No
  - Repair the (Z909) Ground circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE LEFT SEAT CUSHION HEATER ELEMENT FOR AN OPEN
1. Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z909) Ground circuit at the Left Seat Cushion Heater connector (component side).
  Is the resistance between 7.1 and 10.6 Ohms?
  
  Yes
  - Go To 5
  No
  - Replace the Seat Cushion Heater Element in accordance with the Service Information. Refer to PAD, HEATER, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE LEFT SEAT BACK HEATER ELEMENT FOR AN OPEN
1. Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z909) Ground circuit at the Driver Seat Assembly harness connector (seat back side).
  Is the resistance between 8.4 and 12.6 Ohms?
  
  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
  - Replace the Seat Back Heater Element in accordance with the Service Information. Refer to COVER, SEAT BACK, MEGA CAB REAR, REMOVAL .
  - 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. Attempt to reproduce the condition by adjusting the seat.
3. Check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
4. With the scan tool, check for any Environmental Data to help identify the conditions in which the DTC was set.
5. Check Service Bulletins for any possible causes that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Test complete.