Pinpoint Test Q: A Single Climate Controlled Seat is Inoperative - Switch Indicators May Or May Not Illuminate
Seats
Pinpoint Test Q: A Single Climate Controlled Seat is Inoperative - Switch Indicators May Or May Not Illuminate
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information Electrical Diagrams.
Normal Operation
The Dual Climate Controlled Seat Module (DCSM) is supplied voltage from Battery Junction Box (BJB) fuse 67 (40A) to C3265A pin E, circuits SBB08 (VT/RD) and C3265A pin F, circuit SBB08 (VT/RD). The DCSM (Dual Climate Controlled Seat Module) is supplied ground from C3265A pin M, circuit GD138 (BK/WH). 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 engine OFF by using a scan tool to bypass the climate controlled seat switches on the HVAC 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 DCSM (Dual Climate Controlled Seat Module), 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 DCSM (Dual Climate Controlled Seat Module).
The DCSM (Dual Climate Controlled Seat Module) receives all control commands over the Controller Area Network (CAN) communication circuits from the HVAC module which contains the climate controlled seat switches. The climate controlled seat system can only operate if both the HVAC and DCSM (Dual Climate Controlled Seat Module) are communicating correctly on the CAN (Controller Area Network) circuits.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Medium Speed Controller Area Network (MS-CAN) fault
- HVAC module
- DCSM (Dual Climate Controlled Seat Module)
PINPOINT TEST Q : A SINGLE CLIMATE CONTROLLED SEAT IS INOPERATIVE - SWITCH INDICATORS MAY OR MAY NOT ILLUMINATE
NOTE: The air bag warning indicator illuminates when the correct Restraints Control Module (RCM) fuse is removed and the ignition is ON.
NOTE: The Supplemental Restraint System (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.
Q1 CHECK OPERATION OF BOTH CLIMATE CONTROLLED SEATS AND VERIFY THE SYMPTOM
- Check the operation of both climate controlled seats and verify the symptom.
Is only a single climate controlled seat inoperative?
Yes
GO to Q2.
No
If both seats are inoperative, GO to Symptom Chart. Symptom Related Diagnostic Procedures
Q2 CHECK FOR DCSM (Dual Climate Controlled Seat Module) AND HVAC MODULE DTCs
- Enter the following diagnostic mode on the scan tool: Self Test- DCSM (Dual Climate Controlled Seat Module).
- Enter the following diagnostic mode on the scan tool: Self Test- HVAC module.
Were any DTCs retrieved?
Yes
For DCSM (Dual Climate Controlled Seat Module) DTCs, GO to the Dual Climate Controlled Seat Module (DCSM) DTC Chart. Seats
For HVAC module DTCs, REFER to Heating and Air Conditioning to diagnose the HVAC module fault.
No
GO to Q3.
Q3 CHECK OPERATION OF THE DCSM (Dual Climate Controlled Seat Module) USING PIDs
NOTE: The purpose of this step is to verify the DCSM (Dual Climate Controlled Seat Module) is able to receive and process inbound command messages from the communication bus and demonstrate if the DCSM (Dual Climate Controlled Seat Module) is operational. This indicates the HVAC module may not be sending the commands correctly.
- Enter the following diagnostic mode on the scan tool: DataLogger- DCSM (Dual Climate Controlled Seat Module). Driver Seat
- Seat cushion thermal electric device temperature (CSHTEMP)
- Seat back thermal electric device temperature (BK_TEMP)
- Climate-controlled seat heat command (TED (Thermo-Electric Device) _HEAT_D)
Front Passenger Seat
- Passenger Cushion Thermo-Electric Device (TED) Temperature (PCSHTMP)
- Passenger Back TED (Thermo-Electric Device) Temperature (PBKTMP)
- Passenger TED (Thermo-Electric Device) Heat Mode (TED (Thermo-Electric Device) _HEAT_P)
- NOTE: The DCSM (Dual Climate Controlled Seat Module) active commands TED (Thermo-Electric Device) _HEAT_D (driver seat) and TED (Thermo-Electric Device) _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.
- When the command is in process the TED (Thermo-Electric Device) temperature PIDs 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 fan movement.
Do the PID states or cushion blower movement indicate climate controlled seat operation when using the active command?
Yes
GO to Q4.
No
INSTALL a new DCSM (Dual Climate Controlled Seat Module). REFER to Dual Climate Controlled Seat Module (DCSM) . CLEAR the DTCs. REPEAT the self-test.
Q4 USE THE CLIMATE CONTROLLED SEAT SWITCH AND MONITOR THE DCSM (Dual Climate Controlled Seat Module) PID FOR A RESPONSE
- Enter the following diagnostic mode on the scan tool: DataLogger- DCSM (Dual Climate Controlled Seat Module).
- Driver State Seat Mode (DCCSMOD) (driver seat)
- Passenger State Seat Mode (PCCSMOD) (passenger seat)
- Start the engine.
- NOTE: Operation of the climate controlled seats repeatedly ON and OFF or repeatedly switching between heat and cool modes may cause DCSM (Dual Climate Controlled Seat Module) DTCs to set, disabling one or both seat system and may require DTCs to be cleared before seat operation may continue. It is recommended to allow time between modes for seat temperatures to return toward ambient temperatures before continuing.
Attempt to operate the affected climate controlled seat in all modes using the switch buttons while monitoring the DCSM (Dual Climate Controlled Seat Module) PID DCCSMOD (driver seat) or PCCSMOD (passenger seat).
Do all the PID states match the climate controlled seat settings selected?
Yes
If the fault is intermittent, CHECK for causes of the intermittent fault. INSPECT the connectors, terminals and wiring. ATTEMPT to recreate the fault by flexing the wire harness and operating the system. CHECK the electrical connectors for corrosion, poor pin contact or pushed-out pins. REPAIR any intermittent concerns found and TIGHTEN any loose DCSM (Dual Climate Controlled Seat Module) connector pins. CLEAR the DTCs. REPEAT the self-test.
No
INSTALL a new HVAC module. CLEAR the DTCs. REPEAT the self-test.