Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC B242A 01: Seat Heaters Common Circuit Short to BatteryDTC B242A 02: Seat Heaters Common Circuit Short to Ground
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Driver Heated Seat Element Control Terminal 3 X2 | B242A 02 | B2425 0D | B242A 01 | B2425 0E |
Driver Heated Seat Element Control Terminal 1 X2 | B242A 02 | B2425 0D | B242A 01 | B2425 0E |
Driver Heated Seat Cushion Temperature Sensor Signal | B1925 02 | B1925 05 | B1925 05 | B2345 13 |
Driver Heated Seat Cushion Temperature Sensor Low Reference | -- | B1925 05 | -- | B2345 13 |
Passenger Heated Seat Element Control Terminal 5 X2 | B242A 02 | B2430 0D | B242A 01 | B2430 0E |
Passenger Heated Seat Element Control Terminal 2 X2 | B242A 02 | B2430 0D | B242A 01 | B2430 0E |
Passenger Heated Seat Cushion Temperature Sensor Signal | B2170 02 | B2170 05 | B2170 05 | B2345 13 |
Passenger Heated Seat Cushion Temperature Sensor Low Reference | -- | B2170 05 | -- | B2345 13 |
Circuit/System Description
The driver and passenger seat heating elements are controlled by a common low side relay internal to the heated seat module and by individual high side element control circuits. The module connects the heated seat heater element supply voltage circuits for both seats to a common reference point. This reference point is biased to approximately 2.0 V. Before the heated seat module will allow heated seat operation, it checks to see if this reference voltage is shorted to ground or voltage. Once the heated seat module verifies that it is not closing to a shorted heating element, it allows for heated seat operation. The heated seat module will then continue to monitor the heating elements for a shorted circuit.
Conditions for Running the DTC
| • | DTC B1325 must not be present. |
| • | The heated seat module must be powered. |
Conditions for Setting the DTC
B242A 01
The heated seat module detects a short to voltage on the heater element supply voltage circuit or control circuit.
B242A 02
The heated seat module detects a short to ground for on the heater element supply voltage circuit or control circuit.
Action Taken When the DTC Sets
The heated seat function for both seats will be disabled.
Conditions for Clearing the DTC
| • | The current DTC will clear and set a history code 3 seconds after the reference voltage returns to normal operating range and the ignition is cycled OFF then back to ACC or RUN. |
| • | The history DTC will clear after 40 consecutive fault-free ignition cycles have occurred. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Heated Seats Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the X2 harness connector at the K29 heated seat module.
- Test for infinite resistance between the control circuit terminal 3 and ground.
- Test for infinite resistance between the control circuit terminal 5 and ground.
- Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 3 and ground.
- Verify that a test lamp does not illuminate between the control circuit terminal 5 and ground.
- If all circuits test normal, replace the K29 heated seat module.
| ⇒ | If not the specified value, test the control circuit for a short to ground. |
| ⇒ | If not the specified value, test the control circuit for a short to ground. |
| ⇒ | If the test lamp illuminates, test the control circuit for a short to voltage. |
| ⇒ | If the test lamp illuminates, test the control circuit for a short to voltage. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for heated seat module replacement, setup, and programming
