Diagnostic Routine N
Diagnostic Routine N
Diagnostic Overview
A Single Climate Controlled Seat is Inoperative
Refer to Wiring Diagram Set 119 for schematic and connector information Electrical Diagrams.
Normal Operation and Fault Conditions
The DCSM (Dual Climate Controlled Seat Module) is supplied voltage 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 buttons on the touchscreen interface. When commanding a heat or cool mode operation in this manner, it only operates 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 (Diagnostic Trouble Code) specific to either climate controlled seat, only the affected seat is disabled by the DCSM (Dual Climate Controlled Seat Module).
When the climate control seat buttons are activated on the touchscreen interface, this initiates the CAN (Controller Area Network) communication to request climate controlled seat operation. REFER to Network Message Chart .
Pinpoint Test
1. CHECK OPERATION OF BOTH CLIMATE CONTROLLED SEATS AND VERIFY THE SYMPTOM
1. Check the operation of both climate controlled seats and verify the symptom.
Is only a single climate controlled seat inoperative?
2. CHECK FOR DCSM (Dual Climate Controlled Seat Module) DTCs (Diagnostic Trouble Codes)
1. Using a scan tool, perform DCSM (Dual Climate Controlled Seat Module) self-test.
Were any DTCs (Diagnostic Trouble Codes) retrieved during the self-test?
3. CHECK OPERATION OF THE DCSM (Dual Climate Controlled Seat Module) USING PIDs (Parameter Identifications)
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 network and demonstrate if the DCSM (Dual Climate Controlled Seat Module) is operational. This indicates the FCIM (Front Controls Interface Module) may not be sending the commands correctly.
1. Using a scan tool, view DCSM (Dual Climate Controlled Seat Module) driver seat PIDs (Parameter Identifications):
- Seat cushion thermal electric device temperature (CSHTEMP)
- Seat back thermal electric device temperature (BK_TEMP)
- Climate-controlled seat heat command (TED_HEAT_D)
2. Using a scan tool, view DCSM (Dual Climate Controlled Seat Module) front passenger seat PIDs (Parameter Identifications):
- Passenger cushion TED (Thermo-Electric Device) temperature (PCSHTMP)
- Passenger back TED (Thermo-Electric Device) temperature (PBKTMP)
- Passenger TED (Thermo-Electric Device) heat mode (TED_HEAT_P)
3. NOTE: The DCSM (Dual Climate Controlled Seat Module) active commands TED_HEAT_D (driver seat) and TED_HEAT_P (passenger seat) are limited to 15 seconds in the ON state.
Operate the affected climate controlled seat using the active command while monitoring the appropriate PIDs (Parameter Identifications) for that seat.
- When the command is in process the TED (Thermo-Electric Device) temperature PIDs (Parameter Identifications) 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 fan movement.
Do the PID (Parameter Identification) states or cushion blower movement indicate climate controlled seat operation when using the active command?
4. USE THE TOUCHSCREEN BUTTONS AND MONITOR THE DCSM (Dual Climate Controlled Seat Module) PIDs (Parameter Identifications) FOR A RESPONSE
1. Using a scan tool, view DCSM (Dual Climate Controlled Seat Module) PIDs (Parameter Identifications).
- Driver state seat mode (DCCSMOD)
- Passenger state seat mode (PCCSMOD)
2. Start the engine.
3. NOTE: Operation of the climate controlled seats repeatedly on and off or repeatedly switching between heat and cool modes can cause DCSM (Dual Climate Controlled Seat Module) DTCs (Diagnostic Trouble Codes) to set, disabling one or both seat system and can require DTCs (Diagnostic Trouble Codes) to be cleared before seat operation can 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 appropriate buttons on the touchscreen interface while monitoring the DCSM (Dual Climate Controlled Seat Module) PID (Parameter Identification) DCCSMOD (driver seat) or PCCSMOD (passenger seat).
Do all the PIDs (Parameter Identifications) states match the climate controlled seat settings selected on the touchscreen interface?
