Pinpoint Test Q: DTCS B103B and B1111

Seats

Special Tools:

Pinpoint Tests

Pinpoint Test Q: DTCs B103B and B1111

Refer to Wiring Diagrams Set 119, Climate Controlled Seats for schematic and connector information.

Normal Operation

Climate controlled seats are independently controlled by the Dual Climate Controlled Seat Module (DCSM) mounted to the bottom of the passenger seat cushion. The climate controlled seat system only operates with the engine running, however, if using a scan tool to command the DCSM, diagnostic testing can be carried out with the ignition ON. The system receives voltage from Battery Junction Box (BJB) fuse 69 (30A) supplying battery voltage on circuit CBX01 (GN/RD) into DCSM C3265a pin F. The system also receives voltage from BJB fuse 69 (30A) supplying battery voltage on circuit CBX01 (GN/RD) into DCSM C3265a pin E. If voltage is disconnected from either pin E or F of DCSM C3265a with the voltage connection remaining on the other circuit, both seats will remain operational because the voltage supply circuits are connected internally in the DCSM. However, if a fault occurs setting a DTC specific to either climate controlled seat, only the affected seat will be disabled by the module and the other will remain operational.

The seat cushion is equipped with a Thermo-Electric Device (TED) assembly that includes a seat blower (fan motor, serviced as an assembly with the TED). Similarly, the seat backrest is also equipped with its own TED assembly with blower. Cabin air is drawn through the blower and distributed to each of the TED modules located in the seat cushion and backrest. The TEDs then heat or cool the air. The air is then directed into the foam pad and manifold where it is distributed along the surface of the cushion and backrest of the seat. Once the system is activated, the DCSM uses a set of flexible algorithms to control the heating/cooling modes and the blower speed dependant on the HVAC module seat switch settings.

- DTC B103B (Thermo-Electric Driver Overcurrent Low) - If DCSM outputs to the driver seat backrest or cushion TED (circuit pins G, H, J or K at the DCSM connector) or any components within these circuit loops are shorted to ground or a TED resistance of less than 0.9 ohm is sensed, the DCSM will shut down the driver seat system and set this DTC.
- DTC B1111 (Driver Thermo-Electric Device Control Overtemperature Fault) - If the DCSM TED driver integrated circuit temperature exceeds 175°C (347°F), the DCSM will shut down the driver seat system and set this DTC.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- TED assembly
- DCSM



PINPOINT TEST Q: DTCs B103B AND B1111

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.

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