DTC B2425 or B2430 (With Memory)

 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

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performance
Seat Memory Control Module B+ Terminal 5 X4

 B242A 02, B2425 0D, B2430 0D, 1, 2

 B242A 02, B2425 0D, B2430 0D, 1, 2

 -

 -
Driver Heated Seat Temperature Sensor Signal

 B1925 02

 B1925 05

 B1925 05

 -
Passenger Heated Seat Temperature Sensor Signal

 B2170 02

 B2170 05

 B2170 05

 -
Driver Heated Seat Element Control Terminal 11 X3

 B242A 02

 B2425 0D

 B242A 01

 B2425 0B, B2425 0E
Driver Heated Seat Element Control Terminal 6 X3

 B242A 02

 B2425 0D

 B242A 01

 B2425 0B, B2425 0E
Passenger Heated Seat Element Control Terminal 10 X3

 B242A 02

 B2430 0D

 B242A 01

 B2430 0B, B2430 0E
Passenger Heated Seat Element Control Terminal 4 X3

 B242A 02

 B2430 0D

 B242A 01

 B2430 0B, B2430 0E
Driver Heated Seat Temperature Sensor Low Reference

 -

 B1925 05

 -

 -
Passenger Heated Seat Temperature Sensor Low Reference

 -

 B2170 05

 -

 -
1. Power seats inoperative

2. Heated seats inoperative


 Circuit/System Description

The driver and front passenger heated seats are controlled by the seat memory 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 memory 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 memory 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 memory 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 ACCESSORY 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/Vented Seat 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 X4 harness connector at the K40 Seat Memory Control Module.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 5 and ground.
3. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
4. Ignition OFF, disconnect the X3 harness connector at the K40 Seat Memory Control Module.
5.
Note

Element resistance must be measured twice to ensure that all malfunction conditions are simulated. First with the seat unoccupied, then with the seat occupied.


 Test for 1.4-2.5 Ω between terminal 11 and terminal 6.
6. If less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the E14A Seat Heating Element - Driver Back or E14B Seat Heating Element - Driver Cushion.
7. If the value greater than the specified range, test the control circuits for an open circuit/high resistance. If the circuits test normal, replace the E14A Seat Heating Element - Driver Back or E14B Seat Heating Element - Driver Cushion.

8. If all circuits test normal, replace the K40 Seat Memory Control Module.

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

1. Ignition OFF, disconnect the X4 harness connector at the K40 Seat Memory Control Module.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 5 and ground.
3. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
4. Ignition OFF, disconnect the X3 harness connector at the K40 Seat Memory Control Module.
5.
Note

Element resistance must be measured twice to ensure that all malfunction conditions are simulated. First with the seat unoccupied, then with the seat occupied.


 Test for 1.4-2.5 Ω between terminal 10 and terminal 4.
6. If less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the E14C Seat Heating Element - Passenger Back or E14D Seat Heating Element - Passenger Cushion.
7. If the value greater than the specified range, test the control circuits for an open circuit/high resistance. If the circuits test normal, replace the E14C Seat Heating Element - Passenger Back or E14D Seat Heating Element - Passenger Cushion.

8. If all circuits test normal, replace the K40 Seat Memory Control Module.
 Component Testing

Seat Heating Element - Back

Note

Element resistance must be measured twice to ensure that all malfunction conditions are simulated. First with the seat unoccupied, then with the seat occupied.


Test for 0.8-2.4 Ω between terminal 2 and terminal 1.

Seat Heating Element - Cushion

Note

Element resistance must be measured twice to ensure that all malfunction conditions are simulated. First with the seat unoccupied, then with the seat occupied.


Test for 0.8-2.3 Ω between terminal 3 and terminal 4.

 Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.


• Driver Seat Back Cushion Heater Replacement (2/4/6-Way Hybrid, 6-Way Hybrid Sport) Driver Seat Back Cushion Heater Replacement (Driver or Passenger Seat 8-Way Power)

• Driver Seat Cushion Heater Replacement (8-Way Power)

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