Pinpoint Test AE: All Climate Controlled Seats Are Inoperative - Switch Indicators May Or May Not Illuminate
Seats
Pinpoint Tests
Pinpoint Test AE: All Climate Controlled Seats Are Inoperative - Switch Indicators May or May Not Illuminate
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
Climate controlled seat button commands are communicated from the Front Controls Interface Module (FCIM) over the Medium Speed Controller Area Network (MS-CAN) to the HVAC module and then to the Dual Climate Controlled Seat Module (DCSM). Upon receiving a command, the DCSM then communicates indicator illumination commands back to the HVAC module which then commands the FCIM to turn the indicators on or off. The climate controlled seat system can only operate if all 3 modules are communicating correctly on the Controller Area Network (CAN).
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- MS-CAN
- FCIM
- HVAC module
- DCSM
PINPOINT TEST AE: ALL CLIMATE CONTROLLED SEATS ARE INOPERATIVE - SWITCH INDICATORS MAY OR MAY NOT ILLUMINATE
NOTICE: When taking measurements at Dual Climate Controlled Seat Module (DCSM) harness connectors, do not insert the electrical probes into the female connector pins. Inserting the probes into connector pins can cause intermittent or open electrical connections after reassembly resulting in Diagnostic Trouble Codes (DTCs) and system failure. Touching the tip of these connector pins is recommended instead.
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AE1 VERIFY CLIMATE CONTROLLED SEAT BLOWER OPERATION
- Ignition OFF.
- Remove the driver and front passenger cushion Thermo-Electric Device (TED) filters to verify blower operation.
- Turn the filters to the left (counterclockwise) and remove.
- Start the engine.
- Operate climate controlled seat buttons while verifying both blowers operate.
- Does either blower operate?
Yes
If only one blower operates, GO to Symptom Chart to diagnose a single climate controlled seat is inoperative. Symptom Related Diagnostic Procedures
If both blowers operate, GO to AE5.
No
GO to AE2.
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AE2 VERIFY CLIMATE CONTROLLED SEAT INDICATOR ILLUMINATION
- Verify system indicator illumination.
- Does any climate controlled seat indicator illuminate or flash and then turn off?
Yes
GO to AE5.
No
GO to AE3.
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AE3 CHECK THE FCIM FOR DTCs
- Enter the following diagnostic mode on the scan tool: Self Test - FCIM.
- Are any DTCs retrieved?
Yes
REFER to the Master DTC Chart in Body Control Systems. Diagnostic Trouble Code (DTC) Chart
No
GO to AE4.
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AE4 CHECK THE HVAC MODULE FOR DTCs
- Enter the following diagnostic mode on the scan tool: Self Test - HVAC Module.
- Are any DTCs retrieved?
Yes
REFER to the Master DTC Chart in Body Control Systems. Diagnostic Trouble Code (DTC) Chart
No
For vehicles with navigation, GO to AE6.
For vehicles without navigation, GO to AE7.
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AE5 CHECK THE DCSM FOR DTCs
- Enter the following diagnostic mode on the scan tool: Self Test - DCSM.
- Are any DTCs present?
Yes
GO to the Dual Climate Controlled Seat Module (DCSM) DTC Chart. Dual Climate Controlled Seat Module (DCSM) DTC Chart
No
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 connector pins.
REPEAT the self-test.
If no intermittent concerns are found, CARRY OUT the Component Test - Thermo-Electric Device (TED) Cooling Performance for both seats. Component Tests and General Diagnostics
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AE6 MONITOR THE FCIM PIDs AND CHECK THE INPUTS
- Enter the following diagnostic mode on the scan tool: DataLogger - FCIM - PIDs.
- Driver Cooled Seat (CC_SW_D_CL_S)
- Driver Heated Seat (CC_SW_D_HSEATS)
- Passenger Cooled Seat (CC_SW_P_CL_S)
- Passenger Heated Seat (CC_SW_P_HSEATS)
- Monitor the FCIM PIDs while individually pushing driver and passenger climate controlled seat switch buttons.
- Do the PID values agree with the switch positions?
Yes
INSTALL a new HVAC module. TEST the system for normal operation.
No
INSTALL a new FCIM. REFER to Accessories and Optional Equipment. TEST the system for normal operation.
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AE7 CHECK THE HVAC FUNCTIONS
NOTE: The purpose of this step is to verify the HVAC module is able to receive and process inbound command messages from the communication bus and demonstrate the HVAC module is operational. This indicates the climate controlled seat buttons on the FCIM may not be sending the commands.
- Operate the A/C, heater and defrost using the buttons on the FCIM and check for correct HVAC function.
- Does the HVAC system function correctly?
Yes
GO to AE8.
No
REFER to Heating and Air Conditioning to diagnose the HVAC concern.
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AE8 MONITOR THE HVAC MODULE PIDs AND CHECK THE INPUTS
- Enter the following diagnostic mode on the scan tool: DataLogger - HVAC module - PIDs.
- Driver Cooled Seat (CC_SW_D_CL_S)
- Driver Heated Seat (CC_SW_D_HSEATS)
- Passenger Cooled Seat (CC_SW_P_CL_S)
- Passenger Heated Seat (CC_SW_P_HSEATS)
- Monitor the HVAC module PIDs while individually pushing driver and passenger climate controlled seat switch buttons.
- Do the PID values agree with the switch positions?
Yes
GO to AE9.
No
INSTALL a new FCIM. REFER to Accessories and Optional Equipment. TEST the system for normal operation.
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AE9 CHECK THE DCSM USING ACTIVE COMMANDS
- Enter the following diagnostic mode on the scan tool: DataLogger - DCSM - PIDs.
- Seat Cushion Thermal Electric Device Temperature (CSHTEMP)
- Seat Back Thermal Electric Device Temperature (BK_TEMP)
- Climate-controlled Seat Heat Command (TED_HEAT_D)
- Passenger Cushion Thermal Electric Device (TED) Temperature (PCSHTMP)
- Passenger Back (TED) Temperature (PBKTMP)
- Passenger (TED) Heat Mode (TED_HEAT_P)
- NOTE: The DCSM 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 climate controlled seats using active commands while monitoring the appropriate PIDs.
- When the command is in process, the TED temperature PIDs on the seat being commanded 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?
Yes
INSTALL a new FCIM. REFER to Accessories and Optional Equipment. TEST the system for normal operation.
No
INSTALL a new DCSM. REFER to Dual Climate Controlled Seat Module (DCSM) Dual Climate Controlled Seat Module (DCSM). CLEAR the DTCs. REPEAT the self-test.
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