Seat Heaters Self-Diagnostic Function
NOTE: The seat heater control unit has a thermistor self-diagnostic function. It indicates the result by lighting the LEDs of the seat heater switch.
Both the front seat heater control unit and the rear seat heater control unit have a self-diagnostic function.
The self-diagnosis is performed for each control unit.
Use the front seat heater switch to perform the self-diagnosis and read the trouble history on the front side.
Use the rear seat heater switch to perform the self-diagnosis and read the trouble history on the rear side.
How to Use the Self-Diagnostic Function
NOTE: Do steps 2?3 within 10 seconds after doing step 1.

1.
Turn the vehicle to the ON mode.

2.
While pressing the left seat heater switch, press the right seat heater switch three times.

3.
Release the left seat heater switch, and press the right seat heater switch three times.

4.
When the system enters the self-diagnostic mode, all of the seat heater switch indicators turn on for 2 seconds.

5.
All of the seat heater switch indicators alternatively turn on and off every 2 seconds during self-diagnosis.

6.
If any DTC is stored, the system shifts to the LED pattern, which will continue to blink every 2 seconds until the vehicle is turned to the OFF (LOCK) mode.
If no DTCs are stored, the system shifts to the normal control.
During self-diagnostic mode, the control unit blinks the seat heater switch indicators in a specific pattern corresponding to the failure.
One DTC is displayed four times. If more than one failure exists, the next DTC is displayed after 2 seconds.
After all patterns are displayed, the cycle will be repeated until the self-diagnostic mode is off.
The DTC is displayed on either seat heater switch according to where the failure has occurred.
The DTC is displayed using the seat heater switch indicator for the seat in which the failure has been detected.
How to Check for History DTCs
The seat heater control unit can record history DTCs. To read the history DTCs.

NOTE: Do steps 2?3 within 10 seconds after doing step 1.

1.
Turn the vehicle to the ON mode.

2.
Press the left seat heater switch three times.

3.
Press the right seat heater switch six times.

4.
Press the left seat heater switch three times.

5.
When the system enters the trouble history read mode, all of the heater seat indicators turn on for 3 seconds.

6.
If any DTC is stored, the system shifts to the LED pattern, which will continue to blink every 2 seconds until the vehicle is turned to the OFF (LOCK) mode.
If no DTCs are stored, the system shifts to the normal control.
During self-diagnostic mode, the control unit blinks the seat heater switch indicators in a specific pattern corresponding to the failure.
One DTC is displayed four times. If more than one failure exists, the next DTC is displayed after 2 seconds.
After all patterns are displayed, the cycle will be repeated until the self-diagnostic mode is off.
The DTC is displayed on either seat heater switch according to where the failure has occurred.
The DTC is displayed using the seat heater switch indicator for the seat in which the failure has been detected.
Indicator Blink Patterns
How to Clear the DTCs
Whenever the control unit detects failures (failure main heater switch, abnormal heater current, and/or seat not heating), each failure is stored in the control unit.

To clear the DTCs, press and hold the switch for the seat to be cleared for 6 seconds.

NOTE:
When the driver's side (or passenger's side) is cleared, only the DTCs for the applicable side will be cleared.
After clearing the DTCs, all seat heater indicators will turn on for 2 seconds, and then go off.
A thermistor open or a thermistor short failure is stored only when the vehicle ignition in the ON mode. After the vehicle turns to the OFF (LOCK) mode, it is cleared.
If an open or short circuit failure occurs in the thermistor, the self-diagnostic mode display will be displayed after turning the vehicle to the ON mode.
Ending the Self-Diagnostic Function
Turn the vehicle to the OFF (LOCK) mode.