Pinpoint Test AH: DTC B111C
Seats
Pinpoint Tests
Pinpoint Test AH: DTC B111C
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
Both the driver and front passenger climate controlled seats are independently controlled electronically 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 switch ON and the engine OFF. The system receives voltage from Battery Junction Box (BJB) fuse 16 (30A) supplying battery voltage on circuit SBB16 (VT/RD) into DCSM C3036a pins E and F. If voltage is disconnected from either pin E or F of DCSM C3036a with the connection remaining on the other circuit, both seats will remain operational because the 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 DCSM and the other will remain operational.
Each driver and front passenger seat cushion and backrest are equipped with a Thermo-Electric Device (TED) assembly that includes a seat blower (fan motor, serviced as an assembly with the TED). 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 B111C (Passenger Thermo-electric Driver Open Load) - If DCSM outputs to the passenger seat backrest or cushion TED (circuit pins A, B, C or D at the DCSM connector) or any components within these circuit loops are open, disconnected or a TED resistance greater than 90K ohms is sensed, the DCSM continues normal operation and sets this DTC.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- TED assembly
- DCSM
PINPOINT TEST AH: DTC B111C
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.
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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AH1 CHECK THE TED CIRCUITS FOR AN OPEN
- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Air Bag Systems.
- Disconnect: Passenger Seat Side Air Bag C327.
- Disconnect: DCSM C3036a.
- Disconnect: Cushion TED C3328.
- Disconnect: Backrest TED C3326.
- WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment.
- Connect the battery ground cable.
- Measure the resistance of the following circuits.
- Are the resistances less than 5 ohms?
Yes
GO to AH2.
No
REPAIR the affected circuit. REPEAT the self-test. CLEAR the DTCs.
DISCONNECT the battery ground cable.
CONNECT passenger seat side air bag module C327.
REPOWER the SRS. REFER to Air Bag Systems.
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AH2 CHECK THE TED CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between the following DCSM C3036a pins, harness side and ground.
- Is voltage present on any circuits?
Yes
REPAIR the affected circuit. REPEAT the self-test. CLEAR the DTCs.
DISCONNECT the battery ground cable.
CONNECT passenger seat side air bag module C327.
REPOWER the SRS. REFER to Air Bag Systems.
No
GO to AH3.
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AH3 CHECK THE RESISTANCE OF THE TEDs
- Ignition OFF.
- Measure the resistance between backrest TED C3326 pin 1 and pin 3, component side and between cushion TED C3328 pin 1 and pin 3, component side.
- Are the resistances between 0.9 and 10 ohms?
Yes
INSTALL a new DCSM. REFER to Dual Climate Controlled Seat Module (DCSM) Dual Climate Controlled Seat Module (DCSM). REPEAT the self-test.
CLEAR the DTCs.
DISCONNECT the battery ground cable.
CONNECT passenger seat side air bag module C327.
REPOWER the SRS. REFER to Air Bag Systems.
No
If the resistance of the backrest TED was not between 0.9 and 10 ohms, INSTALL a new backrest TED. REFER to Seat Backrest Thermo-Electric Device Seat Backrest Thermo-Electric Device. REPEAT the self-test. CLEAR the DTCs.
If the resistance of the cushion TED was not between 0.9 and 10 ohms, INSTALL a new cushion TED. REFER to Seat Cushion Thermo-Electric Device Seat Cushion Thermo-Electric Device. REPEAT the self-test. CLEAR the DTCs.
DISCONNECT the battery ground cable.
CONNECT passenger seat side air bag module C327.
REPOWER the SRS. REFER to Air Bag Systems.
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