Important: 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 2.0 - 8.0 Ohms between control circuit terminal 6 and control circuit terminal 2.
锟斤拷 If less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat cushion heater
element.
锟斤拷 If greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal, replace the seat cushion
heater element.
3. Disconnect the X2, X4 harness connectors at the HSM.
4. Test for 850 Ohms - 300 kOhms between the signal circuit terminal 20 X4 and the low reference circuit terminal 8 X2.
锟斤拷 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/temperature sensor.
锟斤拷 If greater than the specified range, test the signal and low reference circuits for a short to voltage or an open/high resistance. If the circuits
test normal, replace the seat cushion heater element/temperature sensor.
5. Connect the X1, X2, X4 harness connectors at the HSM.
6. Disconnect the harness connector at the seat cushion heater element/temperature sensor.
7. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal C and ground.
锟斤拷 If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the
HSM.
锟斤拷 If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the HSM.
8. If all circuits test normal, replace the HSM.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Driver or Passenger Seat Cushion Heater Replacement (without HP2) ()Driver or Passenger Seat Cushion Heater Replacement (with HP2)
()
* Control Module References (See: Testing and Inspection/Programming and Relearning) for the HSM replacement, setup, and programming
Rear Seat
DTC B2425 or B2430 (Rear Seat)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B2425 04
- Left Seat Heater Cushion Circuit Open
DTC B2425 0A
- Left Seat Heater Cushion Circuit Rate of Change Below Threshold
DTC B2425 0B
- Left Seat Heater Cushion Circuit Current Above Threshold
DTC B2425 0C
- Left Seat Heater Cushion 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
