Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, record and erase Diagnostic Trouble Codes (DTCs).
3. Operate the Heated Seat Switch in both positions several times.
4. With the scan tool, read DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - The condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension and repair as necessary. Attempt to reproduce condition by adjusting the seat. If no problems are found, test complete.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
CHECK THE (Z960) GROUND CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the HSM harness connector.
3. Disconnect the Left Front Seat Cushion Heater harness connector.
4. Disconnect the Left Front Seat Back Heater harness connector.
5. With a 12-volt test light connected to 12 volts, check the (Z960) Ground circuit at the both the Left Front Seat Cushion and Left Front Seat Back Heater harness connectors (harness side).
  NOTE:
  The test light should 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 (Z960) Ground circuit(s) for an open.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
CHECK THE (P187) LEFT FRONT SEAT HEATER CONTROL CIRCUIT FOR AN OPEN
1. Measure the resistance of the (P187) Left Front Seat Heater Control circuit between the HSM harness connector and the Left Front Seat Cushion and Left Front Seat Back Heater harness connectors (harness side).
  Is the resistance at both connectors below 3.0 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (P187) Left Front Seat Heater Control circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
CHECK THE LEFT SEAT CUSHION HEATER ELEMENT
1. Measure the resistance of the Left Front Seat Cushion Heater between the (P187) Left Front Seat Heater Control circuit and the (Z960) Ground circuit at the Left Front Seat Cushion Heater connector (component side).
  Is the resistance between 4.7 and 7.0 Ohms?
  
  Yes
  - Go To 5
  No
  - Replace the Left Front Seat Cushion Heater Element in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
CHECK THE LEFT SEAT BACK HEATER ELEMENT
1. Measure the resistance of the Left Front Seat Back Heater between the (P187) Left Front Seat Heater Control circuit and the (Z960) Ground circuit at the Left Front Seat Back Heater connector (component side).
  Is the resistance between 5.6 and 8.5 Ohms?
  
  Yes
  - Replace the Heated Seat Module in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
  No
  - Replace the Left Front Seat Back Heater Element in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .