Pinpoint Test I: The Power Lumbar Is Inoperative - Driver

WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Use the correct probe adapter(s) from the Flex Probe Kit when taking measurements. Failure to use the correct probe adapter(s) may damage the connector.

I1 CHECK OTHER SEAT CONTROL SWITCH FEATURES FOR CORRECT OPERATION
- Operate the seat horizontally and vertically.
- Does the seat operate horizontally and vertically?
- Yes : GO to I2.
- No : If equipped with memory, GO to PINPOINT TEST E to diagnose the inoperative seat.
  If not equipped with memory, GO to PINPOINT TEST F to diagnose the inoperative seat.
I2 CHECK FOR VOLTAGE TO THE LUMBAR MOTOR
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 .

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.
- Ignition OFF.
- WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any airbag when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment.
  
  For vehicles equipped with seat side air bags, carry out the following:
  - Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of SUPPLEMENTAL RESTRAINT SYSTEM .
  - Disconnect the driver seat side air bag module C3051.
  - Connect the battery ground cable. Refer to BATTERY, MOUNTING AND CABLES .
- Disconnect: Power Lumbar Motor C3215.
- Measure the voltage between power lumbar motor C3215-B, circuit CPS18 (BN/GN), harness side and power lumbar motor C3215-A, circuit CPS19 (GY/VT), harness side, while operating the lumbar switch in both directions.
  
  Fig 1: Measuring Voltage Between Power Lumbar Motor C3215-B, Circuit CPS18 (BN/GN) And Power Lumbar Motor C3215-A, Circuit CPS19 (GY/VT)
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts when the switch is operated in both directions and 0 volt in the rest position?
- Yes : INSTALL a new power lumbar assembly. REFER to SEAT BACKREST - FRONT, BUCKET SEAT . TEST the system for normal operation.
  For vehicles equipped with seat side air bags, DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C3051. REPOWER the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
- No : GO to I3.
I3 CHECK THE LUMBAR MOTOR CIRCUITS FOR AN OPEN
- Disconnect: Driver Seat Control Switch C369.
- Measure the resistance between:
  - seat control switch C369-7, circuit CPS19 (GY/VT), harness side and power lumbar motor C3215-A, circuit CPS19 (GY/VT), harness side.
  - seat control switch C369-10, circuit CPS18 (BN/GN), harness side and power lumbar motor C3215-B, circuit CPS18 (BN/GN), harness side.
    
    Fig 2: Checking Lumbar Motor Circuits For Open
    Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
- Yes : INSTALL a new seat control switch. REFER to SEAT BACKREST - FRONT, BUCKET SEAT . TEST the system for normal operation.
  For vehicles equipped with seat side air bags, DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C3051. REPOWER the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
- No : REPAIR the circuit. TEST the system for normal operation.
  For vehicles equipped with seat side air bags, DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C3051. REPOWER the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM .