Heated Seats Description and Operation

[Rusty2009]

DTC B2425 or B2430

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: Driver Seat Cushion Heater Circuit High Current

DTC B2425 0D: Driver Seat Cushion Heater Circuit High Resistance

DTC B2425 0E: Driver Seat Cushion Heater Circuit Low Resistance

DTC B2430 0B: Passenger Seat Cushion Heater Circuit High Current

DTC B2430 0D: Passenger Seat Cushion Heater Circuit High Resistance

DTC B2430 0E: Passenger Seat Cushion Heater Circuit Low Resistance

Diagnostic Fault Information

[TR] [TD]Circuit[/TD] [TD]Short to Ground[/TD] [TD]Open/High Resistance[/TD] [TD]Short to Voltage[/TD] [TD]Signal Performance[/TD] [/TR] [TR] [TD]Driver Heated Seat Element Control Terminal 3 X2[/TD] [TD]B242A 02[/TD] [TD]B2425 0D[/TD] [TD]B242A 01[/TD] [TD]B2425 0B, B2425 0E[/TD] [/TR] [TR] [TD]Driver Heated Seat Element Control Terminal 1 X2[/TD] [TD]B242A 02[/TD] [TD]B2425 0D[/TD] [TD]B242A 01[/TD] [TD]B2425 0B, B2425 0E[/TD] [/TR] [TR] [TD]Driver Heated Seat Cushion Temperature Sensor Signal[/TD] [TD]B1925 02[/TD] [TD]B1925 05[/TD] [TD]B1925 05[/TD] [TD]B2345 13[/TD] [/TR] [TR] [TD]Driver Heated Seat Cushion Temperature Sensor Low Reference[/TD] [TD]--[/TD] [TD]B1925 05[/TD] [TD]--[/TD] [TD]B2345 13[/TD] [/TR] [TR] [TD]Passenger Heated Seat Element Control Terminal 5 X2[/TD] [TD]B242A 02[/TD] [TD]B2430 0D[/TD] [TD]B242A 01[/TD] [TD]B2430 0B, B2430 0E[/TD] [/TR] [TR] [TD]Passenger Heated Seat Element Control Terminal 2 X2[/TD] [TD]B242A 02[/TD] [TD]B2430 0D[/TD] [TD]B242A 01[/TD] [TD]B2430 0B, B2430 0E[/TD] [/TR] [TR] [TD]Passenger Heated Seat Cushion Temperature Sensor Signal[/TD] [TD]B2170 02[/TD] [TD]B2170 05[/TD] [TD]B2170 05[/TD] [TD]B2345 13[/TD] [/TR] [TR] [TD]Passenger Heated Seat Cushion Temperature Sensor Low Reference[/TD] [TD]--[/TD] [TD]B2170 05[/TD] [TD]--[/TD] [TD]B2345 13[/TD] [/TR]

Circuit/System Description

The driver and front passenger heated seats are controlled by the seat heating control 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.

• Engine must be running.

• The seat heating control 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 seat heating control 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 seat heating control 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.Note: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat unoccupied, then with the seat occupied.

2. Test for 0.5 - 5 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 backrest heating element and disconnect the X2 harness connector at the K29 seat heating control module.Note: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat unoccupied, then with the seat occupied.

4. Test for 1 - 7 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 seat heating control module.

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

1. Ignition OFF, disconnect the harness connector at the E14C seat back heating element.Note: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat unoccupied, then with the seat occupied.

2. Test for 0.5 - 5 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 backrest heating element and disconnect the X2 harness connector at the K29 seat heating control module.Note: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat unoccupied, then with the seat occupied.

4. Test for 1 - 7 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 seat heating control module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Driver or Passenger Seat Cushion Heater Replacement

• Control Module References for seat heating control module replacement, setup, and programming