Pinpoint Test AA: DTC B111C

WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, and 2011 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

Refer to SYSTEM WIRING DIAGRAMS article, Climate Controlled Seats for schematic and connector information.

NOTE: 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 -- FUSION, MILAN & MKZ article.

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.

AA1 CHECK THE TED CIRCUITS FOR AN OPEN

Ignition OFF.
Depower the SRS. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING article .
Disconnect: Passenger Seat Side Air Bag Module C313.
Disconnect: DCSM C3305A.
Disconnect: Cushion TED C3303.
Disconnect: Backrest TED C3311.

Measure the resistance between DCSM C3305A, harness side and cushion TED C3303, harness side; and between DCSM C3305A, harness side and backrest TED C3311, harness side using the following table:

CONNECTOR REFERENCE TABLE

DCSM Connector	Circuit	TED Connector
C3305A-A	CHS07 (GY/BU)	C3303-1
C3305A-B	RHS07 (BU)	C3303-3
C3305A-C	CHS06 (BU/BN)	C3311-1
C3305A-D	RHS06 (WH)	C3311-3

Fig 1: Measuring Resistance Between DCSM C3305A And Cushion TED C3303

Courtesy of FORD MOTOR CO.

Are the resistances less than 5 ohms?

Yes : GO to AA2 .
No : REPAIR the circuit(s). 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 -- FUSION, MILAN & MKZ article.

AA2 CHECK THE TED CIRCUITS FOR A SHORT TO VOLTAGE

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 & CABLES -- FUSION, MILAN & MKZ article.
Ignition ON.

Measure the voltage between DCSM C3305A, harness side and ground using the following table:

CONNECTOR REFERENCE TABLE

Connector	Circuit
C3305A-A	CHS07 (GY/BU)
C3305A-B	RHS07 (BU)
C3305A-C	CHS06 (BU/BN)
C3305A-D	RHS06 (WH)

Fig 2: Measuring Voltage Between DCSM C3305A, Harness Side And Ground

Courtesy of FORD MOTOR CO.

Is voltage present on any circuits?

Yes : REPAIR the circuit(s). 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 -- FUSION, MILAN & MKZ article.
No : GO to AA3 .

AA3 CHECK THE BACKREST AND CUSHION TED RESISTANCE
- Ignition OFF.
- Measure the resistance between:
  - backrest TED C3311 pin 1 and pin 3, component side.
  - cushion TED C3311 pin 1 and pin 3, component side.
  Fig 3: Measuring Resistance Between Backrest TED C3311 Pin 1 And Pin 3, Component Side
  Courtesy of FORD MOTOR CO.
- Are the resistances between 0.9 and 10 ohms?
1. Yes : INSTALL a new DCSM. REFER to DUAL CLIMATE CONTROLLED SEAT MODULE (DCSM) in this service information. 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 -- FUSION, MILAN & MKZ article.
2. No : If backrest TED resistance is not between 0.9 and 10 ohms, INSTALL a new backrest TED. REFER to SEAT BACKREST THERMO-ELECTRIC DEVICE in this service information. REPEAT the self-test. CLEAR the DTCs.
  If cushion TED resistance is not between 0.9 and 10 ohms, INSTALL a new cushion TED. REFER to SEAT CUSHION THERMO-ELECTRIC DEVICE in this service information.
  
  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 -- FUSION, MILAN & MKZ article.