Heated Seat Switch Indicator Malfunction - Rear

HEATED SEAT SWITCH INDICATOR MALFUNCTION - REAR




DIAGNOSTIC FAULT INFORMATION

IMPORTANT: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure Testing and Inspection

CIRCUIT/SYSTEM DESCRIPTION
The driver and front passenger heated seats are controlled by separate heated seat switches. The switches are located on the rear door panels. When a heated seat switch is pressed, ground from the low reference circuit is momentarily applied through the switch contacts and the switch signal circuit to the heated seat module. In response to this signal, the module then applies battery voltage through the element supply voltage circuits to the seat cushion and seat back heating elements. The heated seat module then supplies a ground through the appropriate indicator control circuits to the heated seat switch illuminating the indicators.

CIRCUIT/SYSTEM VERIFICATION
1. Ignition ON with the heated seat OFF, the heated seat switch mode indicators should be not be illuminated.
2. Ignition ON, use a scan tool to observe the appropriate Seat Indicator Cmd. parameter while pressing the heated seat switch. The reading should change between Off and On.

CIRCUIT/SYSTEM TESTING

HEATED SEAT SWITCH INDICATORS INOPERATIVE
1. Ignition OFF, disconnect the harness connector at the heated seat switch.
2. Ignition ON with the dimmer switch at full illumination, verify that a test lamp illuminates between the supply voltage circuit of the heated seat switch and ground.
- If the test lamp does not illuminate, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the body control module (BCM).
3. Ignition OFF, connect the harness connector to the heated seat switch.
4. Disconnect the harness connector at the rear heated seat module.
5. Ignition ON, connect a test lamp between the inoperative heated seat switch mode indicator control circuit and ground. Verify that the indicator is illuminated.
- If the indicator does not illuminate, test the appropriate indicator control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the heated seat switch.
6. If all circuits test normal, replace the rear heated seat module.

HEATED SEAT SWITCH INDICATORS ALWAYS ON
1. Ignition OFF, disconnect the harness connector at the rear heated seat module.
2. Ignition ON with the heated seat OFF, the heated seat switch mode indicators should not be illuminated.
- If illuminated, test the control circuit of the appropriate indicator for a short to ground. If the circuit tests normal, replace the heated seat switch.
3. If all circuits test normal, replace the rear heated seat module.

COMPONENT TESTING

HEATED SEAT SWITCH
1. Ignition OFF, disconnect the harness connector at the heated seat switch switch.
2. Test for infinite resistance between the signal terminals and the low reference terminal with the switch in the open position.
- If less than infinite, replace the heated seat switch switch.
3. Test for less than 3 ohms between the signal terminals and the low reference terminal with the switch in the closed position.
- If greater than 3 ohms, replace the heated seat switch.

REPAIR INSTRUCTIONS

IMPORTANT: Always perform the after completing the diagnostic procedure.
- Heated Seat Switch Replacement - Rear
- Control Module References for rear heated seat module replacement, setup, and programming
- Control Module References for BCM replacement, setup, and programming