Diagnostic Test

WARNING: This page is about a different car, the 2012 RAM Pickup and 2012 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

TEST FOR INTERMITTENT CONDITION
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).
3. Turn the ignition off.
4. Start the engine and let it run.
5. Turn the Heated Seat on and operate in all modes.
6. Using a scan tool, read DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2.
  No
  - The conditions that caused this code to set are not present at this time. Verify seat harness is routed correctly to the HSM. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. Look for chafed, pierced, pinched, or partially broken wires and broken, bent, pushed out, spread, corroded, or contaminated terminals. Attempt to reproduce condition by adjusting the seat.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK (P187) LEFT FRONT SEAT HEATER CONTROL CIRCUIT FOR AN OPEN

Fig 1: Check Left Front Seat Heater Control Circuit For An Open
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the HSM C2 harness connector.
3. Disconnect the Left Seat Cushion Heater harness connector.
4. Disconnect the Left Seat Back Heater harness connector.
  NOTE:
  Check connectors. Clean and repair as necessary.
5. Measure the resistance of the (P187) Left Front Seat Heater Control circuit between the HSM C2 harness connector and the Left Seat Cushion Heater harness connector.
6. Measure the resistance of the (P187) Left Front Seat Heater Control circuit between the HSM C2 harness connector and the Left Seat Back Heater harness connector.
  Is the resistance below 5.0 Ohms for both measurements?
  
  Yes
  - Go To 3.
  No
  - Repair the (P187) Left Front Seat Heater Control circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK (Z909) GROUND CIRCUIT FOR AN OPEN

Fig 2: Check Ground Circuit For An Open
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance of the (Z909) Ground circuit between ground and the Left Seat Cushion Heater harness connector.
2. Measure the resistance of the (Z909) Ground circuit between ground and the Left Seat Back Heater harness connector.
  Is the resistance below 5.0 Ohms for both measurements?
  
  Yes
  - Go To 4.
  No
  - Repair the (Z909) Ground circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK FOR AN OPEN LEFT SEAT CUSHION HEATER ELEMENT

Fig 3: Check For An Open Left Seat Cushion Heater Element
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z909) Ground circuit at the Left Seat Cushion Heater harness connector.
  Is the resistance above 4.8 Ohms (without vented seats) or 9.8 Ohms (with vented seats)?
  
  Yes
  - Replace the Seat Cushion Heater Element in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5.
CHECK FOR AN OPEN LEFT SEAT BACK HEATER ELEMENT

Fig 4: Check For An Open Left Seat Back Heater Element
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z909) Ground circuit at the Left Seat Back Heater harness connector.
  Is the resistance above 4.8 Ohms (without vented seats) or 11.6 Ohms (with vented seats)?
  
  Yes
  - Repair or replace the pigtail harness for an open or replace the open Seat Back Heater Element in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Repair or replace the pigtail harness for an open or replace the open 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 BODY VERIFICATION TEST .