Pinpoint Test D: The Driver Power Seat Does Not Move Horizontally/Vertically - Vehicles With Sir

WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

Test Step

D1 DETERMINE WHICH DIRECTION HAS FAILED
- Key in OFF position.
- Key in OFF position.
- Operate the power seat forward and rearward.
- Will the track move horizontally?
Result / Action to Take
- Yes : GO to D5.
- No : GO to D2.
D2 CHECK THE VOLTAGE TO FORWARD REVERSE SEAT MOTOR
- Disconnect: Power Seat Motor Assembly C357.
- Measure the voltage between power seat motor assembly C357, circuit 980 (YE/WH), harness side and C357, circuit 981 (RD/WH), harness side while pushing the forward/reverse switch forward and backward.
  
  Fig 1: Checking Voltage Between Connector Terminals
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than -10 volts when the forward/reverse switch is pressed forward, greater than +10 volts when the forward/reverse switch is pressed backward and 0 volts when the switch is in the rest position?
- Yes : INSTALL a new power seat track assembly. REFER to SEAT TRACK - WITH SEAT INTEGRATED RESTRAINTS (SIR) in this article. TEST the system for normal operation.
- No : GO to D3.
D3 CHECK CIRCUIT 980 (YE/WH) FOR AN OPEN AND SHORT TO GROUND
- Disconnect: Seat Regulator Control Switch C360.
- Measure the resistance between seat control switch C360, circuit 980 (YE/WH), harness side and power seat motor assembly C357, circuit 980 (YE/WH), harness side and between seat control switch C360, circuit 980 (YE/WH), harness side and ground.
  
  Fig 2: Checking Circuit 980 (YE/WH) For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between the power seat motor assembly and the seat control switch, and greater than 10,000 ohms between the seat control switch and ground?
- Yes : GO to D4.
- No : REPAIR circuit 980 (YE/WH). TEST the system for normal operation.
D4 CHECK CIRCUIT 981 (RD/WH) FOR AN OPEN AND SHORT TO GROUND
- Measure the resistance between seat control switch C360, circuit 981 (RD/WH), harness side and power seat motor assembly C357, circuit 981 (RD/WH), harness side and between seat control switch C360, circuit 981 (RD/WH), harness side and ground.
  
  Fig 3: Checking Circuit 981 (RD/WH) For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between the power seat motor assembly and the seat control switch, and greater than 10,000 ohms between the seat control switch and ground?
- Yes : INSTALL a new seat control switch. REFER to SEAT CONTROL SWITCH - WITH SEAT INTEGRATED RESTRAINTS (SIR) in this article. TEST the system for normal operation.
- No : REPAIR circuit 981 (RD/WH). TEST the system for normal operation.
D5 DETERMINE SEAT TILTING FAILURE
- Determine seat tilting failure.
- Can the seat be tilted forward or backward?
- Yes : If only the forward tilting operates, GO to D6.
  If only the rear tilting operates, GO to D9.
- No : INSTALL a new seat control switch. REFER to SEAT CONTROL SWITCH - WITH SEAT INTEGRATED RESTRAINTS (SIR) in this article. TEST the system for normal operation.
D6 CHECK THE VOLTAGE TO THE REAR HEIGHT MOTOR
- Disconnect: Power Seat Motor Assembly C357.
- Measure the voltage between power seat motor assembly C357, circuit 983 (RD/LG), harness side and C357, circuit 982 (YE/LG), harness side while depressing the rear tilt switch up and down.
  
  Fig 4: Checking Voltage To Rear Height Motor
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than +10 volts when the rear tilt switch is pressed up, greater than -10 volts when the rear tilt switch is pressed down and 0 volts when the switch is in the rest position?
- Yes : INSTALL a new power seat track assembly. REFER to SEAT TRACK - WITH SEAT INTEGRATED RESTRAINTS (SIR) in this article. TEST the system for normal operation.
- No : GO to D7.
D7 CHECK CIRCUIT 983 (RD/LG) FOR OPEN AND SHORT TO GROUND
- Disconnect: Seat Regulator Control Switch C360.
- Measure the resistance between seat control switch C360, circuit 983 (RD/LG), harness side and power seat motor assembly C357, circuit 983 (RD/LG), harness side and between seat control switch C360, circuit 983 (RD/LG), harness side and ground.
  
  Fig 5: Checking Circuit 983 (RD/LG) For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between the power seat motor assembly and the seat control switch, and greater than 10,000 ohms between the seat control switch and ground?
- Yes : GO to D8.
- No : REPAIR circuit 983 (RD/LG). TEST the system for normal operation.
D8 CHECK CIRCUIT 982 (YE/LG) FOR OPEN AND SHORT TO GROUND
- Measure the resistance between seat control switch C360, circuit 982 (YE/LG), harness side and power seat motor assembly C357, circuit 982 (YE/LG), harness side and between seat control switch C360, circuit 982 (YE/LG), harness side and ground.
  
  Fig 6: Checking Circuit 982 (YE/LG) For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between the power seat motor assembly and the seat control switch, and greater than 10,000 ohms between the seat control switch and ground?
- Yes : INSTALL a new seat control switch. REFER to SEAT CONTROL SWITCH - WITH SEAT INTEGRATED RESTRAINTS (SIR) in this article. TEST the system for normal operation.
- No : REPAIR circuit 982 (YE/LG). TEST the system for normal operation.
D9 CHECK THE VOLTAGE TO FRONT HEIGHT MOTOR - PASSENGER SEAT
- Disconnect: Power Seat Motor Assembly C357.
- Measure the voltage between power seat motor assembly C357, circuit 979 (RD/LB), harness side and circuit 990 (YE/LB), harness side while pushing the rear tilting switch up and down.
  
  Fig 7: Checking Voltage To Front Height Motor - Passenger Seat
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than +10 volts when the front tilt switch is pressed up, greater than -10 volts when the front tilt switch is pressed down and 0 volts when the switch is in the rest position?
- Yes : INSTALL a new power seat track assembly. REFER to SEAT TRACK - WITH SEAT INTEGRATED RESTRAINTS (SIR) in this article. TEST the system for normal operation.
- No : GO to D10.
D10 CHECK CIRCUIT 979 (RD/LB) FOR OPEN AND SHORT TO GROUND
- Disconnect: Seat Control Switch C360.
- Measure the resistance between seat control switch C360, circuit 979 (RD/LB), harness side and power seat motor assembly C357, circuit 979 (RD/LB), harness side and between seat control switch C360, circuit 979 (RD/LB), harness side and ground.
  
  Fig 8: Checking Circuit 979 (RD/LB) For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between the power seat motor assembly and the seat control switch, and greater than 10,000 ohms between the seat control switch and ground?
- Yes : GO to D11.
- No : REPAIR circuit 979 (RD/LB). TEST the system for normal operation.
D11 CHECK CIRCUIT 990 (YE/LB) FOR OPEN
- Measure the resistance between seat control switch C360, circuit 990 (YE/LB), harness side and power seat motor assembly C357, circuit 990 (YE/LB), harness side and between seat control switch C360, circuit 990 (YE/LB), harness side and ground.
  
  Fig 9: Checking Circuit 990 (YE/LB) For Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between the power seat motor assembly and the seat control switch, and greater than 10,000 ohms between the seat control switch and ground?
- Yes : INSTALL a new seat control switch. REFER to SEAT CONTROL SWITCH - WITH SEAT INTEGRATED RESTRAINTS (SIR) in this article. TEST the system for normal operation.
- No : REPAIR circuit 990 (YE/LB). TEST the system for normal operation.