For 1990-2009 cars

### 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 B2425 0B: Left Seat Cushion Heater Circuit High Current
DTC B2425 0D: Left Seat Cushion Heater Circuit High Resistance
DTC B2425 0E: Left Seat Cushion Heater Circuit Low Resistance
DTC B2430 0B: Right Seat Cushion Heater Circuit High Current
DTC B2430 0D: Right Seat Cushion Heater Circuit High Resistance
DTC B2430 0E: Right Seat Cushion Heater Circuit Low Resistance

### 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 front passenger heated seats are controlled by the heated seat module that is located under the driver seat cushion. When the heated seat is active, the module applies power through a common voltage supply circuit to the seat heater elements. The module controls the seat temperature by providing a pulse width modulation (PWM) ground through the seat heater element control circuit to the heater elements. The module then monitors the current flow through the heating elements and the rate of change of the temperature sensor to verify correct heated seat operation.

### Conditions for Running the DTC

• | DTC B1325 must not be present.

• | The heated seat module must be powered and the heated seat must be enabled.

### Conditions for Setting the DTC

#### B2425 0D or B2430 0D

By measuring current and voltage output to the seat heating elements every 10 seconds, the heated seat module calculates that the heating element resistance is above the maximum resistance.

#### B2425 0B, B2425 0E, B2430 0B, or B2430 0E

By measuring current and voltage output to the seat heating elements every 10 seconds, the heated seat module calculates that the heating element resistance is below the minimum resistance.

### Action Taken When the DTC Sets

The heated seat function for the affected seat will be disabled.

### Conditions for Clearing the DTC

• | The current DTC clears when the malfunction is no longer present, and the power mode changes to 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

Heated/Cooled Seat Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Heated Seats Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Testing

#### B2425 0B, B2425 0D, or B2425 0E

1. Ignition OFF, disconnect the harness connector at the E14A seat back heating element.
2. Test for 1.7 - 7.0 Ω between terminal 1 and terminal 2.

⇒ | If not within the specified range, replace the E14A seat back heating element.

3. Connect the harness connector at the E14A seat back heating element and disconnect the X2 harness connector at the K29 heated seat module.
4. Test for 1.7 - 7.0 Ω between control circuit terminal 3 and control circuit terminal 1.

⇒ | If less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the E14B seat cushion heating element.

⇒ | If greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal, replace the E14B seat cushion heating element.

5. If all circuits test normal, replace the K29 heated seat module.

#### B2430 0B, B2430 0D, or B2430 0E

1. Ignition OFF, disconnect the harness connector at the E14C seat back heating element.
2. Test for 1.7 - 7.0 Ω between terminal 1 and terminal 2.

⇒ | If not within the specified range, replace the E14C seat back heating element.

3. Connect the harness connector at the E14C seat back heating element and disconnect the X2 harness connector at the K29 heated seat module.
4. Test for 1.7 - 7.0 Ω between control circuit terminal 5 and control circuit terminal 2.

⇒ | If less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the E14D seat cushion heating element.

⇒ | If greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal, replace the E14D seat cushion heating element.

5. If all circuits test normal, replace the K29 heated seat module.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Driver Seat Cushion Heater Replacement

• | Passenger Seat Cushion Heater Replacement

• | Control Module References for heated seat module replacement, setup, and programming