B19A4

Seats

Pinpoint Test AJ: DTC B19A4

Normal Operation

The Dual Climate Controlled Seat Module (DCSM) supplies voltage and ground to the driver seat backrest Thermo-Electric Device (TED). The DCSM (Dual Climate Controlled Seat Module) also sends a speed control voltage signal to the TED (Thermo-Electric Device) to control blower speed.

- DTC B19A4 (Driver Seat Back Blower Speed Short to Battery)- If the driver seat backrest blower speed circuit is shorted to voltage, the DCSM (Dual Climate Controlled Seat Module) shuts down the driver seat system and sets this DTC.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- TED (Thermo-Electric Device) and blower assembly

- DCSM (Dual Climate Controlled Seat Module)

PINPOINT TEST AJ : DTC B19A4

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: If a seat equipped with a seat mounted side air bag is being serviced, the Supplemental Restraint System (SRS) must be depowered. Refer to Restraints and Safety Systems &/or Air Bag Systems.

NOTE: The air bag warning lamp illuminates when the Restraints Control Module (RCM) fuse is removed and the ignition switch is ON. This is normal operation and does not indicate an SRS (Supplemental Restraint System) fault.

NOTE: The SRS (Supplemental Restraint System) must be fully operational and free of faults before releasing the vehicle to the customer.

AJ1 CHECK THE DRIVER BACKREST TED (Thermo-Electric Device) BLOWER SPEED CONTROL CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Depower the SRS (Supplemental Restraint System). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Restraints and Safety Systems &/or Air Bag Systems.

- Disconnect: Driver Seat Side Air Bag C328.

- Disconnect: Passenger Seat Side Air Bag C327.

- Disconnect: DCSM (Dual Climate Controlled Seat Module) C3036C.

- 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.

- Ignition ON.

- Measure the voltage between DCSM (Dual Climate Controlled Seat Module) C3036C-12, circuit VHS16 (BU/GN), harness side and ground.






Is any voltage present?

Yes
GO to AJ2.

No
GO to AJ3.

AJ2 CHECK THE DRIVER BACKREST TED (Thermo-Electric Device) BLOWER SPEED CONTROL CIRCUIT FOR A SHORT TO VOLTAGE

- Disconnect: Driver Backrest TED (Thermo-Electric Device) C3322.

- Measure the voltage between DCSM (Dual Climate Controlled Seat Module) C3036C-12, circuit VHS16 (BU/GN), harness side and ground.






Is any voltage present?

Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

DISCONNECT the battery ground cable.

CONNECT driver seat side air bag module C328 and passenger seat side air bag module C327.

REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.

No
GO to AJ3.

AJ3 CHECK THE DRIVER BACKREST TED (Thermo-Electric Device) BLOWER SPEED CONTROL AND BLOWER OUTPUT CIRCUITS FOR A SHORT TOGETHER

- Ignition OFF.

- Disconnect: Driver Backrest TED (Thermo-Electric Device) C3322.

- Measure the resistance between DCSM (Dual Climate Controlled Seat Module) C3036C-12, circuit VHS16 (BU/GN), harness side and C3036C-16, circuit CHS03 (GN/BN), harness side.






Is the resistance greater than 10,000 ohms?

Yes
GO to AJ4.

No
REPAIR the circuits. CLEAR the DTCs. REPEAT the self-test.

DISCONNECT the battery ground cable.

CONNECT driver seat side air bag module C328 and passenger seat side air bag module C327.

REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.

AJ4 CHECK THE BACKREST TED (Thermo-Electric Device) RESISTANCE FOR AN INTERNAL SHORT

- Measure the resistance between driver backrest TED (Thermo-Electric Device) C3322 pin 2 and pin 7, component side.






Is the resistance greater than 2,000,000 ohms?

Yes
INSTALL a new DCSM (Dual Climate Controlled Seat Module). 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 driver seat side air bag module C328 and passenger seat side air bag module C327.

REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.

No
INSTALL a new backrest TED (Thermo-Electric Device). REFER to Seat Backrest Thermo-Electric Device Seat Backrest Thermo-Electric Device. CLEAR the DTCs. REPEAT the self-test.

CONNECT driver seat side air bag module C328 and passenger seat side air bag module C327.

REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.