B2425
DTC B2425 or B2430
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B2425 0D
- Left Seat Heater Cushion Circuit Resistance Above Threshold
DTC B2425 0E
- Left Seat Heater Cushion Circuit Resistance Below Threshold
DTC B2430 0D
- Right Seat Heater Cushion Circuit Resistance Above Threshold
DTC B2430 0E
- Right Seat Heater Cushion Circuit Resistance Below Threshold
Diagnostic Fault Information
Circuit/System Description
The left and right rear passenger heated seats are controlled by the rear heated seat module (RHSM). When active, power is applied to the seat cushion and back heater elements through a common voltage supply circuit. Each individual heater element is grounded by the heated seat module through separate low side drive control circuits. The heater element control circuits are pulse width modulated to ground by the module in order to control the seat temperatures by regulating the current flow through the heater elements. The module then monitors the current flow through the heating elements and the of rate change of the temperature sensors to verify correct heated seat operation.
Conditions for Running the DTC
The heated seat system must be active.
Conditions for Setting the DTC
B2425 0D, B2430 0D
By measuring the current and voltage output to the seat cushion heating element every 10 seconds, the RHSM calculates that the heating element resistance is above the maximum resistance value of 13.2 ohms.
B2425 0E, B2430 0E
By measuring the current and voltage output to the seat cushion heating element every 10 seconds, the RHSM calculates that the heating element resistance is below the minimum resistance value of 5.4 ohms.
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 50 consecutive fault-free ignition cycles have occurred.
Reference Information
Schematic Reference
Heated/Cooled Seat Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Rear Heated Seats Description and Operation (Rear Heated Seats Description and Operation)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Testing
B2425 0D or B2425 0E
1. Ignition OFF, disconnect the X1 harness connector at the RHSM.
Important: When measuring the resistance, all of the resistance values below are based on the seat being at room temperature of 20°C (68°F).
2. Test for 5.4-13.2 ohms between the control terminal 3 and control circuit terminal 5.
• If greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal, replace the seat cushion heating element.
• If less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat cushion heating element.
3. If all circuits test normal, replace the RHSM.
B2430 0D or B2430 0E
1. Ignition OFF, disconnect the X1 harness connector at the RHSM.
Important: When measuring the resistance, all of the resistance values below are based on the seat being at room temperature of 20°C (68°F).
2. Test for 5.4-13.2 ohm between the control circuit terminal 6 and control circuit terminal 2.
• If greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal, replace the seat cushion heating element.
• If less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat cushion heating element.
3. If all circuits test normal, replace the RHSM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Rear Seat Cushion Heater Replacement (Rear Seat Cushion Heater Replacement)
* Control Module References (Programming and Relearning) for RHSM replacement, setup, and programming