Climate Controlled Seat Control Unit: Fail-safe

WARNING: This page is about a different car, the 2009 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.

Climate controlled seat control unit equips fail-safe function.
When a malfunction occurs in the systems shown as per the following, climate controlled seat control unit stops output.

MALFUNCTION CONDITION CHART

Malfunction

Malfunctioning condition

The temperature difference between the seatback thermal electric device and seat cushion thermal electric device is 30°C or more

When it detects for 4 seconds that the temperature difference between the seatback thermal electric device and seat cushion thermal electric device is 30°C or more, stops the output to the thermal electric device, activates the climate controlled seat blower motor in the maximum position, and sends the external airflow for 30 seconds
If the temperature difference is still 30°C or more after 30 seconds pass, it stops all output and enters the system OFF condition
When the temperature difference between seatback thermal electric device and seat cushion thermal electric device becomes 20°C or less, the system recovers automatically
If it detects that the temperature difference is 30°C or more after the automatic system recovery, it immediately stops all output and enters the system OFF condition
NOTE: When the switch operation is performed before entering the system OFF condition, the fail-safe mode is reset.

The temperature of thermal electric device is 110°C or more in the HEAT mode (any thermal electric device in the seatback or seat cushion)

When it detects for 4 seconds that the temperature of the thermal electric device is 110°C or more, stops the output to the thermal electric device, activates the climate controlled seat blower motor in the maximum position, and sends the external airflow for 30 seconds
If the temperature does not become 105°C or less after 30 seconds pass, it stops all output and enters the system OFF condition
When the temperature of the thermal electric device becomes 105°C or less, the system recovers automatically
If it detects that the temperature of the thermal electric device is 110°C or more after the automatic system recovery, it immediately stops all output and enters the system OFF condition

The temperature of the thermal electric device is 45°C or more in the COOL mode (any thermal electric device in the seatback or seat cushion)

When it detects for 4 seconds that the temperature of the thermal electric device is between 45°C and 70°C, it starts the temperature monitoring of the thermal electric device at 3 second intervals
While monitoring, if it detects that the temperature raises 2°C or more 4 times continuously or reaches 70°C or more, it stops all output and enters the system OFF condition
If it detects other results of monitoring, it continues activating in the COOL mode

Thermal electric device sensor system open circuit

When it detects for 4 seconds that the thermal electric device sensor system is an open circuit

Climate controlled seat blower motor system open circuit

When it detects for 2 seconds that climate controlled seat blower motor system is an open circuit while the climate controlled seat is being activated, it stops output to the thermal electric device
When it detects for 10 seconds that the climate controlled seat blower motor system is an open circuit while the climate controlled seat is being activated, it stops all output and enters the system OFF condition
NOTE: After detecting the climate seat blower motor system open circuit for 2 seconds, the system recovers automatically if the activation of the climate controlled seat blower motor is detected for 1 second or more.

Switch input out of the specified range

When it detects for 4 seconds that the rotary switch input is 30% or less of the vehicle battery voltage, it stops all output and enters the system OFF condition
When the switch input returns to a value within the specified range, the system recovers automatically

HEAT or COOL switch input out of the specified range

When it detects for 4 seconds that rotary switch input is 6% or less of the vehicle battery voltage, it stops all output and enters the system OFF condition
When the switch input returns to a value within the specified range, the system recovers automatically

System voltage out of range

System voltage⁽¹⁾ of the climate controlled seat control unit is out of the operation range (8.5 V - 16.5 V)

⁽¹⁾	System voltage is the voltage between climate controlled seat control unit power source and the ground.

NOTE: When the system enters in the fail-safe mode again after performing resetting procedure, perform diagnosis.