CLIMATE CONTROLLED SEAT SYSTEM: Fail-safe

WARNING: This page is about a different car, the 2013 Infiniti M56 and 2013 Infiniti M37. 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 below, climate controlled seat control unit stops output.

Malfunction

Malfunctioning condition

The temperature difference between the seatback thermal electric unit and seat cushion thermal electric unit is more than 40°C

When it detects for 4 seconds that the temperature difference between the seatback thermal electric unit and seat cushion thermal electric unit is more than 40°, it stops the output to the thermal electric unit, activates the climate controlled seat blower motor at the maximum position, and sends the external airflow for 30 seconds.
If the temperature difference is still more than 40°C after 30 seconds pass, it stops all output and enters the system OFF condition.
When the temperature difference between seatback thermal electric unit and seat cushion thermal electric unit becomes less than 20°C, the system recovers automatically.
If it detects that the temperature difference is more than 40°C 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 unit is more than 110°C in the HEAT mode (any thermal electric unit in the seatback or seat cushion)

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

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

When it detects for 4 seconds that the temperature of the thermal electric unit is more than 45°C and less than 70°C, it starts the temperature monitoring of the thermal electric unit at 3 second intervals.
While monitoring, if it detects that the temperature continuously rises 2°C or more 4 times 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 unit sensor open circuit (in either the back and the cushion)

When it detects for 4 seconds that the thermal electric unit sensor is an open circuit, it stops all output and enters the system OFF condition.

Climate controlled seat blower motor system open circuit (in the cushion blower)

When it detects for 2 seconds that climate controlled seat blower motor is an open circuit while the climate controlled seat is being activated, and the battery status has been stable for the same 2 second period, it stops output to the thermal electric unit.
When it detects for 10 seconds that the climate controlled seat blower motor is an open circuit while the climate controlled seat is being activated, and the battery status has been stable for the same 10 second period, 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 (either heat input or cool input)

When it detects for 4 seconds that the rotary switch input is less than 30% 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

During the standby mode, heating or cooling states, if the 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

If the system voltage at the climate controlled seat control unit falls outside of the 8.5 to 16.5 V operating range, it stops all output after a 500ms time period.
When the system voltage returns to the normal operating range (10.5-15.5V with a 500ms hysteresis), the system recovers automatically.

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

NOTE: When the ignition status changes to OFF during the fail-safe mode, the control unit shall enter the OFF condition. If the ignition is turned ON, the system shall return to the standby mode. If the system enters in the fail-safe mode again after performing ignition cycle, start the diagnosis.