Diagnostic Test
- CHECK FOR AN ACTIVE DTC
- With the scan tool, read DTCs and record on the repair order.
- Record the Environmental Data.
- With the scan tool, erase DTCs.
- Start the Engine.
- Turn the Left Front Heated Seat on.
- With the scan tool, read CSWM DTCs.
Is the same DTC active?
Yes
- Go To 2
No
- Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
- CHECK THE (P187) LEFT FRONT SEAT HEATER CONTROL CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
- Turn the ignition off.
- Disconnect the Left Front Seat Cushion Heater harness connector.
- Disconnect the Left Front Seat Back Heater harness connector.
- Disconnect the CSWM C2 harness connector.
- Connect a jumper wire between B(+) and the (P187) Left Front Seat Heater Control circuit at the CSWM C2 harness connector.
- With 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(s) for an open or high resistance.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
- CHECK THE (Z941) GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
- Disconnect the jumper wire.
- With a 12-volt test light connected to 12 volts, check the (Z941) Ground circuit at the Left Front Seat Cushion and Left Front Seat Back Heater harness connectors (harness side).
Does the test light illuminate brightly at both connectors?
Yes
- Go To 4
No
- Repair the (Z941) Ground circuit(s) for an open or high resistance.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
- CHECK THE LEFT FRONT SEAT CUSHION HEATER ELEMENT RESISTANCE
- Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z941) Ground circuit at the Left Front Seat Cushion Heater component connector.NOTE:
For non-vented seats the resistance value should measure between 4.1 and 6.2 Ohms. For vented seats the resistance value should measure between 3.9 and 5.9 Ohms.
Is the measured resistance within specified values?
Yes
- Go To 5
No
- Replace the Left Front Seat Cushion Heater Element in accordance with the Service Information. Refer to PAD, HEATER, REMOVAL AND INSTALLATION .
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
- Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z941) Ground circuit at the Left Front Seat Cushion Heater component connector.
- CHECK THE LEFT FRONT SEAT BACK HEATER ELEMENT RESISTANCE
- Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z941) Ground circuit at the Left Front Seat Back Heater component connector.NOTE:
For non-vented seats the resistance value should measure between 5.5 and 8.2 Ohms. For vented seats the resistance value should measure between 7.8 and 11.8 Ohms.
Is the measured resistance within specified values?
Yes
- Go To 6
No
- Replace the Left Front Seat Back Heater Element in accordance with the Service Information. Refer to PAD, HEATER, REMOVAL AND INSTALLATION .
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
- Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z941) Ground circuit at the Left Front Seat Back Heater component connector.
- CHECK RELATED HARNESS CONNECTIONS
- Disconnect all CSWM harness connectors.
- Disconnect all related in-line harness connections (if equipped).
- Disconnect the related component harness connectors.
- 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.
- Connect all CSWM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
- Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
- Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
- With the scan tool, erase DTCs.
- Test drive or operate the vehicle in accordance with the when monitored and set conditions.
- With the scan tool, read CSWM DTCs.
Is the same DTC active?
Yes
- Replace the Comfort Seat Wheel Module (CSWM) in accordance with the Service Information. Refer to MODULE, COMFORT SEAT AND WHEEL (CSWM), REMOVAL AND INSTALLATION .
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
No
- Repairing the wiring harness or connections corrected the problem.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .