Pinpoint Test AE: The Power Lumbar Is Inoperative - Driver

NOTE: The air bag warning indicator illuminates when the correct Restraints Control Module (RCM) fuse is removed and the ignition is ON.

NOTE: The Supplemental Restraint System (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.

AE1 CHECK THE POWER LUMBAR MOTOR FOR VOLTAGE
- Depower the SRS . Refer to Supplemental Restraint System (SRS) Depowering and Repowering .
- Disconnect: Driver Seat Side Air Bag C367.
- Disconnect: Driver Safety Belt Buckle C3065.
- Disconnect: Power Lumbar Motor C3215.
- 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 Removal and Installation .
- 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 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 11 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 LUMBAR ASSEMBLY - POWER in this article. TEST the system for normal operation.
  DISCONNECT the battery ground cable. CONNECT driver seat side air bag C367 and driver seat safety belt buckle C3065. REPOWER the SRS . REFER to Supplemental Restraint System (SRS) Depowering and Repowering .
- No : GO to AE2 .
AE2 CHECK THE LUMBAR MOTOR CIRCUITS FOR AN OPEN
- Disconnect: 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: Measuring Resistance Between Seat Control Switch C369-10, Circuit CPS18 (BN/GN) And Power Lumbar Motor C3215-B, Circuit CPS18 (BN/GN)
    Courtesy of FORD MOTOR CO.
Are the resistances less than 3 ohms?
- Yes : INSTALL a new seat control switch. REFER to SEAT CONTROL SWITCH - FRONT in this article. TEST the system for normal operation.
  DISCONNECT the battery ground cable. CONNECT driver seat side air bag C367 and driver seat safety belt buckle C3065. REPOWER the SRS . REFER to Supplemental Restraint System (SRS) Depowering and Repowering .
- No : REPAIR the circuit. TEST the system for normal operation.
  DISCONNECT the battery ground cable. CONNECT driver seat side air bag C367 and driver seat safety belt buckle C3065. REPOWER the SRS . REFER to Supplemental Restraint System (SRS) Depowering and Repowering .