• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Driver Heated Seat Back Element Supply Voltage | B2508 02 | B1935 0D | B2508 01 | B1935 0E |
Driver Heated Seat Back Element Control | B2508 02 | B1935 0D | B2508 01 | B1935 0E |
Driver Heated Seat Back Temperature Sensor Signal | B2435 02 | B2435 05 | B2435 05 | B2345 13, B2345 42, B2345 4B |
Driver Heated Seat Back Temperature Sensor Low Reference | -- | B2435 05 | -- | B2345 13, B2345 42, B2345 4B |
Driver Heated Seat Cushion Element Supply Voltage | B2508 02 | B2425 0D | B2508 01 | B2425 0E |
Driver Heated Seat Cushion Element Control | B2508 02 | B2425 0D | B2508 01 | B2425 0E |
Driver Heated Seat Cushion Temperature Sensor Signal | B1925 02 | B1925 05 | B1925 05 | B2345 13, B2345 42, B2345 4B |
Driver Heated Seat Cushion Temperature Sensor Low Reference | -- | B1925 05 | -- | B2345 13, B2345 42, B2345 4B |
Passenger Heated Seat Back Element Supply Voltage | B2508 02 | B2180 0D | B2508 01 | B2180 0E |
Passenger Heated Seat Back Element Control | B2508 02 | B2180 0D | B2508 01 | B2180 0E |
Passenger Heated Seat Back Temperature Sensor Signal | B2440 02 | B2440 05 | B2440 05 | B2345 13, B2345 42, B2345 4B |
Passenger Heated Seat Back Temperature Sensor Low Reference | -- | B2440 05 | -- | B2345 13, B2345 42, B2345 4B |
Passenger Heated Seat Cushion Element Supply Voltage | B2508 02 | B2430 0D | B2508 01 | B2430 0E |
Passenger Heated Seat Cushion Element Control | B2508 02 | B2430 0D | B2508 01 | B2430 0E |
Passenger Heated Seat Cushion Temperature Sensor Signal | B2170 02 | B2170 05 | B2170 05 | B2345 13, B2345 42, B2345 4B |
Passenger Heated Seat Cushion Temperature Sensor Low Reference | -- | B2170 05 | -- | B2345 13, B2345 42, B2345 4B |
The driver and passenger heated seat heating elements are controlled by a common high current relay internal to the memory seat module (MSM) and the low side by individual element control circuits. The MSM connects the heated seat heater element supply voltage circuits for both seats to a common reference point. This reference point is biased to approximately 2.0 volts. Before the MSM will allow heated seat operation, it checks to see if this reference voltage is shorted to ground or battery voltage. Once the module verifies that it is not closing to a shorted heating element, it allows heated seat operation. After which it continues to monitor for a shorted circuit.
The MSM must be powered.
Any temperature sensor input that remains below 1.5 volts for more than 1 second.
This DTC will set if the module calibration data set is not present.
This DTC will set if the module calibration is out of range.
The heated seat function for both seats will be disabled.
• | The current DTC will clear and set the code to history 3 seconds after the reference voltage returns to the normal operating range and the ignition is cycled OFF then back to ACC or RUN. |
• | The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred. |
Heated Seats Description and Operation
Control Module References for scan tool information
• | Driver seat cushion terminal 1 X5 and terminal 3 X2 |
• | Passenger seat cushion terminal 2 X5 and terminal 6 X2 |
⇒ | If less than the specified value, test for a short between the signal and low reference circuits. If the circuits test normal, replace the appropriate seat cushion temperature sensor. |
• | Driver seat back terminal 4 X5 and terminal 2 X2 |
• | Passenger seat back terminal 3 X5 and terminal 5 X2 |
⇒ | If less than the specified value, test for a short between the signal and low reference circuits. If the circuits test normal, replace the appropriate seat back temperature sensor. |
If either DTC is set, replace the MSM.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for MSM replacement, setup and programming |