Circuit Description
The driver seat module (DSM) controls the voltage supply and the ground circuits to the driver and passenger seat heater elements. When a heated seat function is commanded active, the seat module will switch battery voltage to the heater element supply circuits, and ground is provided through low side drive control circuits. During heated seat operation both the seat back and cushion heater elements are supplied battery voltage. The seat module grounds the appropriate control circuits for driver or passenger heated seat operation, and opens or closes the active control circuits, as necessary, in order to maintain the desired seat temperature.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC B2425 Driver Seat Heater Circuit |
| • | DTC B2430 Passenger Seat Heater Circuit |
Conditions for Running the DTC
| • | Battery voltage to the seat module must be within 8-17 volts. |
| • | Heated seat operation is attempted. |
Conditions for Setting the DTC
| • | One of the low side drive control circuits is shorted to voltage or ground. |
| • | One of the heater element voltage supply circuits is shorted to voltage or ground. |
Action Taken When the DTC Sets
The seat module will disable heated seat operation.
Conditions for Clearing the DTC
| • | The DTC will be stored as a history code when the fault is no longer present. |
| • | A history DTC will be cleared after completing 100 consecutive ignition cycles. |
Diagnostic Aids
If the DTC is only found in history, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Driver Seat Schematics , Passenger Seat Schematics Connector End View Reference: Power Seat Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the heated seat system operate normally? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
3 |
Does the test lamp illuminate? | Go to Step 5 | Go to Step 4 |
4 | Connect a test lamp from battery voltage to the seat heater element control circuit terminal in the seat module harness connector. Does the test lamp illuminate? | Go to Step 6 | Go to Step 7 |
5 | Repair the seat heater element voltage supply or control circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 9 | -- |
6 | Repair the seat heater element voltage supply or control circuit for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to Step 9 | -- |
7 | Inspect for poor connections at the driver seat module (DSM). Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 8 |
8 | Replace the DSM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Is the repair complete? | Go to Step 9 | -- |
9 |
Does the DTC reset? | Go to Step 2 | System OK |
