Pinpoint Test K: All Climate Controlled Seats Are Inoperative - Rear
Seats
Pinpoint Test K: All Climate Controlled Seats Are Inoperative - Rear
Normal Operation
The Passenger Climate Controlled Seat Module - 2 (PCSM-2) is supplied voltage from Battery Junction Box (BJB) fuse 7 (30A) to C3365A pins E and F, circuit SBB07 (WH/RD). The PCSM-2 (Passenger Climate Controlled Seat Module - 2) is supplied ground from C3365A pin M, circuit GD133 (BK). Both voltage supply circuits are hot at all times but the climate controlled seat system only operates with the engine running. The system can be operated with the ignition ON by using a scan tool to bypass the climate controlled seat switches on the Rear Heating Ventilation Air Conditioning (RHVAC) module and when commanding a heat or cool mode operation in this manner will only operate in 15-second intervals. Both voltage supply circuits are spliced together internal to the PCSM-2 (Passenger Climate Controlled Seat Module - 2), so if one circuit becomes open, both seats can still be operated. However, if a fault occurs setting a DTC specific to either climate controlled seat, only the affected seat will be disabled by the PCSM-2 (Passenger Climate Controlled Seat Module - 2).
The PCSM-2 (Passenger Climate Controlled Seat Module - 2) receives all control commands over the Controller Area Network (CAN) communication circuits from the RHVAC (Rear Heating Ventilation Air Conditioning) module which contains the climate controlled seat switches. The climate controlled seat system can only operate if both the RHVAC (Rear Heating Ventilation Air Conditioning) module and PCSM-2 (Passenger Climate Controlled Seat Module - 2) are communicating correctly on the CAN (Controller Area Network) circuits.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Medium Speed Controller Area Network (MS-CAN) fault
- RHVAC (Rear Heating Ventilation Air Conditioning) module
- PCSM-2 (Passenger Climate Controlled Seat Module - 2)
PINPOINT TEST K : ALL CLIMATE CONTROLLED SEATS ARE INOPERATIVE - REAR
K1 CHECK FOR PCSM-2 (Passenger Climate Controlled Seat Module - 2) AND RHVAC (Rear Heating Ventilation Air Conditioning) MODULE DTCs
- Enter the following diagnostic mode on the scan tool: Self Test- PCSM-2 (Passenger Climate Controlled Seat Module - 2).
- Enter the following diagnostic mode on the scan tool: Self Test- RHVAC (Rear Heating Ventilation Air Conditioning) Module.
Are any DTCs retrieved?
Yes
For PCSM-2 (Passenger Climate Controlled Seat Module - 2) DTCs, GO to the Passenger Climate Controlled Seat Module - 2 (PCSM-2) DTC Chart. Seats
For RHVAC (Rear Heating Ventilation Air Conditioning) module DTCs, REFER to Heating and Air Conditioning to diagnose the RHVAC (Rear Heating Ventilation Air Conditioning) module fault.
No
If either the PCSM-2 (Passenger Climate Controlled Seat Module - 2) or RHVAC (Rear Heating Ventilation Air Conditioning) module does not respond to the scan tool, REFER to Information Bus to diagnose the concern.
If module communication is OK, CHECK the climate control system operation and REFER to Heating and Air Conditioning to diagnose any concerns found.
Otherwise, GO to K2.
K2 CHECK OPERATION OF THE PCSM-2 (Passenger Climate Controlled Seat Module - 2) USING PIDs
NOTE: The purpose of this step is to verify the PCSM-2 (Passenger Climate Controlled Seat Module - 2) is able to receive and process inbound command messages from the communication bus and demonstrate if the PCSM-2 (Passenger Climate Controlled Seat Module - 2) is operational. This indicates the RHVAC (Rear Heating Ventilation Air Conditioning) module may not be sending the commands correctly.
- Enter the following diagnostic mode on the scan tool: DataLogger- PCSM-2 (Passenger Climate Controlled Seat Module - 2). Driver Side Seat
- Seat cushion thermal electric device temperature (CSHTEMP)
- Seat back thermal electric device temperature (BK_TEMP)
- Climate-controlled seat heat command (TED_HEAT_D)
Passenger Side Seat
- Passenger Cushion Thermo-Electric Device (TED) Temperature (PCSHTMP)
- Passenger Back TED Temperature (PBKTMP)
- Passenger TED Heat Mode (TED_HEAT_P)
- NOTE: The PCSM-2 (Passenger Climate Controlled Seat Module - 2) active commands TED_HEAT_D (driver seat) and TED_HEAT_P (passenger seat) are limited to 15 seconds in the ON state, then turn OFF.
Operate the affected climate controlled seat using the active command while monitoring the appropriate PIDs for that seat.
- When the command is in process the TED (Thermo-Electric Device) temperature PIDs on the affected seat should momentarily increase. If no temperature increase is noted, remove the cushion blower filter and repeat the active command while physically monitoring the cushion blower for movement.
Do the PID states or cushion blower movement indicate climate controlled seat operation when using the active command?
Yes
INSTALL a new RHVAC (Rear Heating Ventilation Air Conditioning) module. TEST the system for normal operation.
No
INSTALL a new PCSM-2 (Passenger Climate Controlled Seat Module - 2). REFER to Passenger Climate - Controlled Seat Module (PCSM-2) . CLEAR the DTCs. REPEAT the self-test.