B2425
DTC B2425 or B2430
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* 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 04
- Left Seat Cushion Heater Circuit Open
DTC B2425 0A
- Left Seat Cushion Heater Circuit Rate of Change Below Threshold
DTC B2425 0B
- Left Seat Cushion Heater Circuit Current Above Threshold
DTC B2425 0C
- Left Seat Cushion Heater Circuit Current Below Threshold
DTC B2425 0D
- Left Seat Heater Cushion Circuit Resistance Above Threshold
DTC B2425 0E
- Left Seat Heater Cushion Circuit Resistance Below Threshold
DTC B2425 1F
- Left Seat Cushion Heater Circuit Intermittent
DTC B2430 04
- Right Seat Cushion Heater Circuit Open
DTC B2430 0A
- Right Seat Cushion Heater Circuit Rate of Change Below Threshold
DTC B2430 0B
- Right Seat Cushion Heater Circuit Current Above Threshold
DTC B2430 0C
- Right Seat Cushion Heater Circuit Current Below Threshold
DTC B2430 0D
- Right Seat Heater Cushion Circuit Resistance Above Threshold
DTC B2430 0E
- Right Seat Heater Cushion Circuit Resistance Below Threshold
DTC B2430 1F
- Right Seat Cushion Heater Circuit Intermittent
Diagnostic Fault Information
Circuit/System Description
When the heated seat function is active, the Memory Seat Module (MSM) supplies battery voltage through the element supply voltage circuit to the seat heater elements. The module controls the seat temperature by providing a pulse width modulated (PWM) ground through the heated seat element control circuit to the seat heater elements. The module then monitors the current flow through the heating element and the temperature sensor rate of change to verify correct operation.
Conditions for Running the DTC
The MSM must be powered and the heated seat must be enabled.
Conditions for Setting the DTC
B2425 04, B2430 04
The module does not detect a temperature change within 210 seconds.
B2425 0A, B2430 0A
The module detects that the set point temperature has not been reached within 8.5 minutes.
B2425 0B, B2425 0E, B2430 0B, B2430 0E
By measuring output current, the module calculates that the heating element resistance is below the minimum resistance.
B2425 0C, B2445 0D, B2430 0C, B2430 0D
By measuring output current, the module calculates that the heating element resistance is above the maximum resistance.
B2425 1F, B2430 1F
The temperature sensor voltage is erratic or changes suddenly.
Action Taken When the DTC Sets
The heated seat cushion 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.
Circuit/System Testing
B2425
1. Ignition OFF, disconnect the X1 harness connector at the MSM.
2. Test for less than 15 ohms between the heater element supply voltage circuit terminal 14 and the control circuit terminal 11.
^ If the resistance is greater than 15 ohms test the supply and control circuits for an open/high resistance. If the circuits test normal replace the seat cushion heater element.
3. Disconnect the X2, X5 harness connectors at the MSM.
4. Test for 850-300k ohms between the temperature sensor signal circuit terminal 1 X5 and the low reference circuit terminal 3 X2.
^ If greater than the specified range, test the signal circuit and low reference circuit for a short to voltage or an open/high resistance. If the circuits test normal, replace the seat cushion heater element.
^ If less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat cushion heater element.
5. Connect the X1, X2, X5 harness connectors at the MSM.
6. Disconnect the harness connector at the seat cushion heater element.
7. Ignition ON, test for 4.8-5.2 volts between the temperature sensor signal circuit terminal C and ground.
^ If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
^ If less than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
8. If all circuits test normal, replace the MSM.
B2430 Front
1. Ignition OFF, disconnect the X1, X4 harness connector at the MSM.
2. Test for less than 15 ohms between the heater element supply voltage circuit terminal 6 X1 and the control circuit terminal 14 X4.
^ If the resistance is greater than 15 ohms test the supply and control circuits for an open/high resistance. If the circuits test normal replace the seat cushion heater element.
3. Disconnect the X2, X5 harness connectors at the MSM.
4. Test for 850-300k ohms between the temperature sensor signal circuit terminal 2 X5 and the low reference circuit terminal 6 X2.
^ If greater than the specified range, test the signal circuit and low reference circuit for a short to voltage or an open/high resistance. If the circuits test normal, replace the seat cushion heater element.
^ If less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat cushion heater element.
5. Connect the X1, X2, X4, X5 harness connectors at the MSM.
6. Disconnect the harness connector at the seat cushion heater element.
7. Ignition ON, test for 4.8-5.2 volts between the temperature sensor signal circuit terminal C and ground.
^ If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
^ If less than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
8. If all circuits test normal, replace the MSM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Driver Seat and Passenger Seat Cushion Heater Replacement