Pinpoint Test L: The Power Lumbar Is Inoperative - Driver

WARNING: This page is about a different car, the 2014 Lincoln MKX and 2014 Ford Edge. 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 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.

L1 CHECK FOR VOLTAGE TO THE POWER SEAT CONTROL SWITCH
- Ignition OFF.
- Depower the SRS . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Disconnect: Driver Seat Side Air Bag C328.
- Disconnect: Driver Seat Control Switch C3016.
- 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 .
- Measure the voltage between C3016-5 , circuit SBB23 (WH/RD) (without memory seat) or SBP07 (WH/RD) (with memory seat), harness side and ground.
  
  Fig 1: Measuring Voltage Between (C3016-5), Circuit SBB23 (WH/RD), Harness Side And Ground (Without Memory Seat)
  Courtesy of FORD MOTOR CO.
Is the voltage greater than 10 volts?
- Yes : GO to L2 .
- No : VERIFY Body Control Module (BCM) fuse 7 (7.5A) (with memory seat) or Battery Junction Box (BJB) fuse 23 (30A) (without memory seat) is OK. If OK, REPAIR the circuit. If not OK, REFER to the SYSTEM WIRING DIAGRAMS to identify possible causes of the circuit short. TEST the system for normal operation.
  DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C328.
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
L2 CHECK THE POWER SEAT CONTROL SWITCH GROUND FOR AN OPEN
- Measure the resistance between driver seat control switch C3016-3 , circuit GD145 (BK/BU), harness side and ground.
  
  Fig 2: Measuring Resistance Between Driver Seat Control Switch (C3016-3), Circuit GD145 (BK/BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
Is the resistance less than 5 ohms?
- Yes : GO to L3 .
- No : REPAIR the circuit. TEST the system for normal operation.
  DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C328.
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
L3 CHECK FOR VOLTAGE TO THE POWER LUMBAR MOTOR
- Connect: Driver Seat Control Switch C3016.
- Disconnect: Power Lumbar Motor C3215.
- NOTE: During the following step, the voltage being measured changes polarity dependent upon which direction the seat control switch is activated.
  
  While operating the seat control switch in both directions, measure the voltage between power lumbar motor C3215-1 , circuit CPS19 (GY/VT), harness side and power lumbar motor C3215-2 , circuit CPS18 (BN/GN), harness side.
  
  Fig 3: Measuring Voltage Between Power Lumbar Motor (C3215-1), Circuit CPS19 (GY/VT) And Power Lumbar Motor (C3215-2), Circuit CPS18 (BN/GN)
  Courtesy of FORD MOTOR CO.
Is the voltage greater than 10 volts when the seat control switch is operated 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 driver seat side air bag module C328.
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
- No : GO to L4 .
L4 CHECK THE POWER LUMBAR MOTOR CIRCUITS FOR A SHORT TO GROUND
- Disconnect: Driver Seat Control Switch C3016.
- Measure the resistance between:
  - driver seat control switch C3016-10 , circuit CPS19 (GY/VT), harness side and ground.
  - driver seat control switch C3016-7 , circuit CPS18 (BN/GN), harness side and ground.
    
    Fig 4: Measuring Resistance Between Driver Seat Control Switch (C3016-10), Circuit CPS19 (GY/VT), Harness Side And Ground
    Courtesy of FORD MOTOR CO.
Are the resistances greater than 10, 000 ohms?
- Yes : GO to L5 .
- No : REPAIR the circuit. TEST the system for normal operation.
  DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C328.
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
L5 CHECK THE LUMBAR MOTOR CIRCUITS FOR AN OPEN
- Measure the resistance between:
  - seat control switch C3016-10 , circuit CPS19 (GY/VT), harness side and power lumbar motor C3215-1 , circuit CPS19 (GY/VT), harness side.
  - seat control switch C3016-7 , circuit CPS18 (BN/GN), harness side and power lumbar motor C3215-2 , circuit CPS18 (BN/GN), harness side.
    
    Fig 5: Measuring Resistance Between Seat Control Switch (C3016-10), Circuit CPS19 (GY/VT) And Power Lumbar Motor (C3215-1), Circuit CPS19 (GY/VT)
    Courtesy of FORD MOTOR CO.
Are the resistances less than 5 ohms?
- Yes : INSTALL a new seat control switch. REFER to SEAT CONTROL SWITCH - FRONT . TEST the system for normal operation.
  DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C328.
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .
- No : REPAIR the circuit. TEST the system for normal operation.
  DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C328.
  
  REPOWER the SRS . REFER to SUPPLEMENTAL RESTRAINT SYSTEM .