B3642

DTC B3642

CIRCUIT DESCRIPTION
The seat cool temperature switch is normally open. When the switch is pressed, its contacts are closed to ground pulling the cooled seat signal circuit low signaling the door control module of the cooled seat command. The door control module then sends a GMLAN message to the memory seat module (MSM) indicating the cooled seat request. The MSM then sends a pulse width modulation (PWM) signal to the climate control seat module (CCSM) indicating the cooled seat request. In response to this signal, the CCSM activates the requested cooled seat mode.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B3642 Seat Cooler Switch Circuit

CONDITIONS FOR RUNNING THE DTC
The door module must be powered and cannot have B1327 - Battery Voltage Low or B1328 - Battery Voltage High set as an active DTC for this DTC to set.

CONDITIONS FOR SETTING THE DTC
If the door control module detects that the seat cool temperature switch circuit is active for 30 continuous seconds, the switch will be considered shorted and the DTC will set.

ACTION TAKEN WHEN THE DTC SETS
No other heated/cooled seat switch activations shall be recognized as a result of this switch circuit being active.

CONDITIONS FOR CLEARING THE DTC
The DTC automatically clears when the switch circuit setting the DTC is no longer active.

TEST DESCRIPTION

Step 1 - Step 10:

The number below refers to the step number on the diagnostic table.
2. This step checks the existing state of the seat cool temperature switch by using the current state of the input parameter.