Pinpoint Test R: The Heated Seat Is Inoperative - Driver

WARNING: This page is about a different car, the 2010 Mercury Milan, 2010 Lincoln MKZ, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

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

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

R1 CHECK HEATED SEAT OPERATION
- Start the engine.
- Verify the passenger heated seat is operational.
- Is the passenger heated seat operational?

Yes : GO to R2.
No : GO to SYMPTOM TABLE to diagnose the heated seats are inoperative - driver and front passenger or the heated seat is inoperative/does not operate correctly - passenger.

R2 CHECK HEATED SEAT INDICATOR ILLUMINATION
- Verify system indicator illumination.
- Do the driver heated seat indicators illuminate or flash and then turn off?

Yes : GO to R7.
No : Vehicles with navigation, GO to R3.
Vehicles without navigation, GO to R4.

R3 RETRIEVE THE FCIM DTCs
- Enter the following diagnostic mode on the scan tool: Self Test - FCIM .
- Are any FCIM DTCs retrieved?

Yes : For all FCIM DTCs, REFER to the Master DTC Table in MULTIFUNCTION ELECTRONIC MODULES .
No : GO to R4.

R4 RETRIEVE THE HVAC MODULE DTCs
- Enter the following diagnostic mode on the scan tool: Self Test - HVAC Module.
- Are any HVAC module DTCs retrieved?

Yes : If DTC B1030:12, GO to R18.
If DTC B1030:14, GO to R19.

For any other HVAC module DTCs, REFER to the HVAC MODULE DTC TABLE .
No : For vehicles with navigation, GO to R5.
For vehicles without navigation, GO to R6.

R5 MONITOR THE DRIVER HEATED SEAT (CC_SW_D_HSEATS) PID AND CHECK INPUTS
- Enter the following diagnostic mode on the scan tool: DataLogger - FCIM - PIDs: CC_SW_D_HSEATS.
- Monitor the FCIM PID while pushing the driver heated seat button.
- Do the PID states agree with the switch button positions?

Yes : GO to R6.
No : INSTALL a new FCIM . REFER to INFORMATION AND ENTERTAINMENT SYSTEMS . TEST the system for normal operation.

R6 MONITOR THE DRIVER HEATED SEAT (CC_SW_D_HSEATS) PID AND CHECK INPUTS
- Enter the following diagnostic mode on the scan tool: DataLogger - HVAC Module - PIDs: CC_SW_D_HSEATS.
- Monitor the HVAC module PID while pushing the driver heated seat button.
- Do the PID values agree with the switch button positions?

Yes : The fault is intermittent, CHECK for causes of the intermittent fault. INSPECT the connectors, terminals and wiring. ATTEMPT to recreate the fault by flexing the wire harness and operating the system. CHECK the electrical connectors for corrosion, poor pin contact or pushed-out pins. REPAIR any intermittent concerns found and TIGHTEN any loose connector pins. REPEAT the self-test. CLEAR the DTCs. CHECK the system for normal operation.
No : INSTALL a new HVAC module. REFER to CLIMATE CONTROL . TEST the system for normal operation.

R7 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- Ignition OFF.
- Depower the SRS . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Disconnect: Driver Seat Side Air Bag Module C327.
- Disconnect: Passenger Seat Side Air Bag Module C313.
- Disconnect: Heated Seat Module C3304b.
  WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module 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 heated seat module C3304b-1, circuit SBP18 (YE/RD) harness side and ground.
  
  Fig 1: Measuring Voltage Between Heated Seat Module C3304B-1, Circuit SBP18 (YE/RD) Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?

Yes : GO to R8.
No : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R8 CHECK THE TEMPERATURE SENSOR OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: Heated Seat Module C3304a.
- Disconnect: Driver Seat Cushion Heater Mat C364.
- Ignition ON.
- Measure the voltage between heated seat module C3304a-3, circuit VHS26 (VT), harness side and ground.
  
  Fig 2: Measuring Voltage Between Heated Seat Module C3304A-3, Circuit VHS26 (VT), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is any voltage present?

Yes : REPAIR the circuit. GO to R11 to check the temperature sensor for damage. If OK, TEST the system for normal operation. If not OK, INSTALL a new driver seat cushion heater mat. REFER to SEAT CUSHION COVER - FRONT .
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES
No : GO to R9.

R9 CHECK THE TEMPERATURE SENSOR OUTPUT CIRCUIT FOR AN OPEN AND SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between:
  - heated seat module C3304a-3, circuit VHS26 (VT), harness side and rear seat cushion heater mat C364-3, circuit VHS26 (VT), harness side.
  - heated seat module C3304a-3, circuit VHS26 (VT), harness side and ground.
  Fig 3: Checking Temperature Sensor Output Circuit For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between C3304a-3 and C364-3, and greater than 10,000 ohms between C3304a-3 and ground?

Yes : GO to R10.
No : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R10 CHECK THE TEMPERATURE SENSOR RETURN CIRCUIT FOR AN OPEN
- Measure the resistance between heated seat module C3304a-12, circuit RHS05 (YE/VT), harness side and driver seat cushion heater mat C364-4, circuit RHS05 (YE/VT), harness side.
  
  Fig 4: Checking Temperature Sensor Return Circuit For Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?

Yes : GO to R11.
No : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R11 CHECK THE TEMPERATURE SENSOR FOR AN OPEN
- Measure the resistance between rear heated seat cushion C364 pin 3 and pin 4, component side.
  
  Fig 5: Measuring Resistance Between Rear Heated Seat Cushion C364 Pin 3 And Pin 4, Component Side
  Courtesy of FORD MOTOR CO.
- Is the resistance between 300 ohms and 300,000 ohms?

Yes : GO to R12.
No : INSTALL a new cushion heater mat. REFER to SEAT CUSHION COVER - FRONT . TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R12 CHECK THE HEATER MAT OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between heated seat module C3304b-4, circuit CHS02 (YE/BU), harness side and ground.
  
  Fig 6: Measuring Voltage Between Heated Seat Module C3304B-4, Circuit CHS02 (YE/BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is any voltage present?

Yes : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES
No : GO to R13.

R13 CHECK THE HEATER MAT OUTPUT CIRCUIT FOR AN OPEN AND SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between:
  - heated seat module C3304b-4, circuit CHS02 (YE/BU), harness side and cushion heater mat C364-1, circuit CHS02 (YE/BU), harness side.
  - heated seat module C3304b-4, circuit CHS02 (YE/BU), harness side and ground.
  Fig 7: Checking Heater Mat Output Circuit For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between C3304b-4 and C364-1, and greater than 10,000 ohms between C3304b-4 and ground?

Yes : GO to R14.
No : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R14 CHECK THE HEATER MAT RESISTANCE
- Connect: Driver Seat Backrest Heater Mat C365.
- Connect: Driver Seat Cushion Heater Mat C364.
- Measure the resistance between heated seat module C3304b-4, circuit CHS02 (YE/BU), harness side and ground.
  
  Fig 8: Measuring Resistance Between Heated Seat Module C3304B-4, Circuit CHS02 (YE/BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance between 1.2 and 4.0 ohms?

Yes : GO to R21.
No : GO to R15.

R15 CHECK THE CUSHION HEATER MAT FOR AN OPEN
- Disconnect: Driver Seat Cushion Heater Mat C364.
- Measure the resistance between driver seat cushion heater mat C364 pins 1 and 2, component side.
  
  Fig 9: Measuring Resistance Between Driver Seat Cushion Heater Mat C364 Pins 1 And 2, Component Side
  Courtesy of FORD MOTOR CO.
- Is the resistance between 0.6 and 2.0 ohms?

Yes : GO to R16.
No : INSTALL a new driver seat cushion heater mat. REFER to SEAT CUSHION COVER - FRONT . TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R16 CHECK THE CIRCUIT BETWEEN THE CUSHION HEATER MAT AND BACKREST HEATER MAT FOR AN OPEN AND SHORT TO GROUND
- Disconnect: Driver Seat Backrest Heater Mat C365.
- Measure the resistance between:
  - seat cushion heater mat C364-2, circuit CHS11 (VT/GN), harness side and seat backrest heater mat C365-1, circuit CHS11 (VT/GN), harness side.
  - seat cushion heater mat C364-2, circuit CHS11 (VT/GN), harness side and ground.
  Fig 10: Checking Circuit Between Cushion Heater Mat And Backrest Heater Mat For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?

Yes : GO to R17.
No : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R17 CHECK THE BACKREST HEATER MAT FOR AN OPEN
- Measure the resistance between driver seat backrest heater mat C365 pins 1 and 2, component side.
  
  Fig 11: Measuring Resistance Between Driver Seat Backrest Heater Mat C365 Pins 1 And 2, Component Side
  Courtesy of FORD MOTOR CO.
- Is the resistance between 0.6 and 2.0 ohms?

Yes : REPAIR circuit GD126 (BK/WH) for an open. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES
No : INSTALL a new driver seat backrest heater mat. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R18 CHECK HEATED SEAT MODULE SWITCH INPUT CIRCUIT FOR SHORT TO VOLTAGE
- Ignition OFF.
- Depower the SRS . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Disconnect: Passenger Seat Side Air Bag Module C313.
- Disconnect: Heated Seat Module C3304a.
- Disconnect: HVAC Module C2356a.
  WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module 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 .
- Ignition ON.
- Measure the voltage between heated seat module C3304a-2, circuit CHS29 (WH/BU), harness side and ground.
  
  Fig 12: Measuring Voltage Between Heated Seat Module C3304A-2, Circuit CHS29 (WH/BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is any voltage present?

Yes : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES
No : INSTALL a new HVAC module. REFER to CLIMATE CONTROL . TEST the system for normal operation. DISCONNECT the battery ground cable.
CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R19 CHECK THE HEATED SEAT MODULE SWITCH INPUT CIRCUIT FOR AN OPEN
- Ignition OFF.
- Depower the SRS . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Disconnect: Passenger Seat Side Air Bag Module C313.
- Disconnect: Heated Seat Module C3304a.
- Disconnect: HVAC Module C2356a.
  WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module 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 resistance between heated seat module C3304a-2, circuit CHS29 (WH/BU), harness side and HVAC module C2356a-5, circuit CHS29 (WH/BU), harness side.
  
  Fig 13: Checking Heated Seat Module Switch Input Circuit For Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?

Yes : GO to R20.
No : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R20 CHECK THE HEATED SEAT MODULE SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between heated seat module C3304a-2, circuit CHS29 (WH/BU), harness side and ground.
  
  Fig 14: Measuring Resistance Between Heated Seat Module C3304A-2, Circuit CHS29 (WH/BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?

Yes : INSTALL a new heated seat module. REFER to HEATED SEAT MODULE . TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES
No : REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

R21 CHECK THE HVAC MODULE OUTPUT
- Connect: Heated Seat Module C3304a and C3304b.
- Ignition ON.
  NOTE: The following measurement must be taken by back-probing heated seat module C3304a.
  
  NOTE: Voltage on circuit CHS29 (WH/BU) should drop momentarily when the driver heated seat control button is pressed.
- Measure the voltage between heated seat module C3304a-2, circuit CHS29 (WH/BU), harness side and ground by back-probing heated seat module connector. Press the driver heated seat button on the HVAC module and note the voltage.
  
  Fig 15: Measuring Voltage Between Heated Seat Module C3304A-2, Circuit CHS29 (WH/BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts before pressing the driver heated seat control button, then momentarily drops when the heated seat control button is pressed?

Yes : INSTALL a new heated seat module. REFER to HEATED SEAT MODULE . TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES
No : If voltage is greater than 10 volts but did not drop when the driver heated seat button was pressed, INSTALL a new HVAC module. REFER to CLIMATE CONTROL . TEST the system for normal operation.
If voltage is less than 10 volts, INSTALL a new heated seat module. REFER to HEATED SEAT MODULE . TEST the system for normal operation.

DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C327. CONNECT passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES