Pinpoint Test I: The Power Lumbar Is Inoperative - Passenger

WARNING: This page is about a different car, the 2014 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: If a seat equipped with a seat mounted side air bag is being repaired, 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.

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 : GO to PINPOINT TEST B to diagnose the inoperative seat.
I2 CHECK FOR VOLTAGE TO THE LUMBAR MOTOR
- Ignition OFF.
- Depower the SRS . Refer to SUPPLEMENTAL RESTRAINT SYSTEM .
- Disconnect: Passenger Seat Side Air Bag Module C339 .
- Disconnect: Power Lumbar Motor C3216 .
- 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.
  
  Connect the battery ground cable. Refer to BATTERY, MOUNTING AND CABLES .
- NOTE: During the following step, the voltage being measured changes polarity dependent upon which direction the seat control switch is activated.
  
  Measure the voltage between power lumbar motor C3216-B , circuit CPS18 (BN/GN), harness side and power lumbar motor C3216-A , circuit CPS19 (GY/VT), harness side, while operating the lumbar switch in both directions.
  
  Fig 1: Checking Lumbar Motor For Voltage
  Courtesy of FORD MOTOR CO.
Is the voltage greater than 10 volts when the lumbar switch is operated in both directions and 0 volt in the rest position?
- Yes : INSTALL a new power lumbar assembly. REFER to LUMBAR ASSEMBLY - POWER . TEST the system for normal operation.
  DISCONNECT the battery ground cable.
  
  CONNECT passenger seat side air bag module C339 .
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
- No : GO to I3 .
I3 CHECK THE LUMBAR MOTOR CIRCUITS FOR AN OPEN
- Disconnect: Passenger Seat Control Switch C330 .
- Measure the resistance between:
  - seat control switch C330-10 , circuit CPS20 (VT), harness side and power lumbar motor C3216-B , circuit CPS18 (BN/GN), harness side.
  - seat control switch C330-7 , circuit CPS21 (WH/OG), harness side and power lumbar motor C3216-A , circuit CPS19 (GY/VT), 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 CONTROL SWITCH .
  TEST the system for normal operation.
  
  DISCONNECT the battery ground cable.
  
  CONNECT passenger seat side air bag module C339 .
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
- No : REPAIR the circuit(s). TEST the system for normal operation.
  DISCONNECT the battery ground cable.
  
  CONNECT passenger seat side air bag module C339 .
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .