Pinpoint Test AC: DTC B19A1
Seats
Pinpoint Test AC: DTC B19A1
Refer to Wiring Diagram Set 119 (Fusion/Milan/MKZ, Fusion Hybrid, Milan Hybrid, MKZ Hybrid), Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
The Dual Climate Controlled Seat Module (DCSM) supplies voltage and ground to the passenger seat cushion Thermo-Electric Device (TED). The DCSM also sends a speed control voltage signal to the TED to control blower speed.
- DTC B19A1 (Passenger Seat Cushion Blower Speed Short to Battery) - If the passenger seat cushion blower speed circuit is shorted to voltage, the DCSM will shut down the passenger seat system and set this DTC.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- TED and blower assembly
- DCSM
PINPOINT TEST AC: DTC B19A1
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 Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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 fault.
NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
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AC1 CHECK THE CUSHION TED BLOWER MOTOR SPEED CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Passenger Seat Side Air Bag C313.
- Disconnect: DCSM C3305C.
- 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. Refer to Battery, Mounting and Cables Battery Disconnect.
- Ignition ON.
- Measure the voltage between C3305C-3, circuit VHS23 (BN/BU), harness side and ground.
- Is any voltage present?
Yes
GO to AC2.
No
GO to AC3.
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AC2 CHECK THE CUSHION TED BLOWER MOTOR SPEED CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: Cushion TED C3303.
- Measure the voltage between DCSM C3305C-3, circuit VHS23 (BN/BU), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit. REPEAT the self-test. CLEAR the DTCs.
DISCONNECT the battery ground cable.
CONNECT passenger seat side air bag module C313.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
GO to AC3.
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AC3 CHECK THE CUSHION TED BLOWER MOTOR SPEED CONTROL AND BLOWER MOTOR FEED CIRCUITS FOR A SHORT TOGETHER
- Ignition OFF.
- Disconnect: Cushion TED C3303.
- Measure the resistance between DCSM C3305C-3, circuit VHS23 (BN/BU), harness side and C3305C-8, circuit CHS08 (BN/YE), harness side.
- Is the resistance greater than 10,000 ohms?
Yes
GO to AC4.
No
REPAIR the circuits. REPEAT the self-test. CLEAR the DTCs.
DISCONNECT the battery ground cable.
CONNECT passenger seat side air bag module C313.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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AC4 CHECK THE CUSHION TED RESISTANCE FOR AN INTERNAL SHORT
- Measure the resistance between cushion TED C3303 pin 2 and pin 7, component side.
- Is the resistance greater than 2,000,000 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 C313.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
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 C313.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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