Pinpoint Test P: The Heated Seats Are Inoperative - Rear

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.

WARNING: Never install heated seat parts not intended for use on this vehicle. Parts released for other model years or vehicle lines are not compatible even if they appear visually and physically similar. Installing incorrect parts will result in heated seat system performance outside design specification. Failure to follow this instruction may result in serious personal injury.

P1 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- Disconnect: Heated Seat Module C3162A.
- Ignition ON.
- Measure the voltage between:
  - heated seat module C3162A-1 , circuit SBB30 (BN/RD), harness side and ground.
  - heated seat module C3162A-2 , circuit CBP34 (BK), harness side and ground.
  - heated seat module C3162A-3 , circuit SBB30 (BN/RD), harness side and ground.
    
    Fig 1: Measuring Voltage Between Heated Seat Module (C3162A-1), Circuit SBB30 (BN/RD), Harness Side And Ground
    Courtesy of FORD MOTOR CO.
Are the voltages greater than 10 volts?
- Yes : GO to P2 .
- No : VERIFY Battery Junction Box (BJB) fuse 30 (30A) and Body Control Module (BCM) fuse 34 (10A) are OK. If OK, REPAIR the affected circuit. If not OK, REFER to the SYSTEM WIRING DIAGRAMS to identify possible causes of the circuit short. TEST the system for normal operation.
P2 CHECK THE HEATED SEAT MODULE GROUND
- Ignition OFF.
- Measure the resistance between heated seat module C3162A-5 , circuit GD133 (BK), harness side and ground.
  
  Fig 2: Measuring Resistance Between Heated Seat Module (C3162A-5), Circuit GD133 (BK), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
Is the resistance less than 5 ohms?
- Yes : GO to P3 .
- No : REPAIR the circuit. TEST the system for normal operation.
P3 CHECK THE SENSOR RETURN CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: Heated Seat Module C3162B.
- Ignition ON.
- Measure the voltage between heated seat module C3162B-12 , circuit RHS41 (GN/BN), harness side and ground.
  
  Fig 3: Measuring Voltage Between Heated Seat Module (C3162B-12), Circuit RHS41 (GN/BN), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
Is any voltage present?
- Yes : REPAIR the circuit. TEST the system for normal operation.
- No : GO to P4 .
P4 CHECK THE SENSOR RETURN CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between heated seat module C3162B-12 , circuit RHS41 (GN/BN), harness side and ground.
  
  Fig 4: Measuring Resistance Between Heated Seat Module (C3162B-12), Circuit RHS41 (GN/BN), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
Is the resistance greater than 10, 000 ohms?
- Yes : GO to P5 .
- No : REPAIR the circuit. TEST the system for normal operation.
P5 CHECK THE SENSOR RETURN CIRCUIT FOR AN OPEN
- Disconnect: Right Rear Heated Seat C3169.
- Measure the resistance between heated seat module C3162B-12 , circuit RHS41 (GN/BN), harness side and right rear heated seat C3169-3 , circuit RHS41 (GN/BN), harness side.
  
  Fig 5: Measuring Resistance Between Heated Seat Module (C3162B-12), Circuit RHS41 (GN/BN) And Right Rear Heated Seat (C3169-3), Circuit RHS41 (GN/BN)
  Courtesy of FORD MOTOR CO.
Is the resistance less than 5 ohms?
- Yes : INSTALL a new heated seat module. REFER to HEATED SEAT MODULE - REAR SEAT . TEST the system for normal operation.
- No : REPAIR the circuit. TEST the system for normal operation.