Pinpoint Test S: The Heated Seat Is Inoperative - Passenger

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.

S1 CHECK HEATED SEAT OPERATION
- Ignition OFF.
- Start the engine.
- Verify the driver heated seat is operational.
- Is the driver heated seat operational?

Yes : GO to S2.
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 - driver.

S2 CHECK HEATED SEAT INDICATOR ILLUMINATION
- Verify system indicator illumination.
- Do the passenger heated seat indicators illuminate or flash and then turn off?

Yes : GO to S7.
No : Vehicles with navigation, GO to S3.
Vehicles without navigation, GO to S4.

S3 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 S4.

S4 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 B1032:12, GO to S18.
If DTC B1032:14, GO to S19.

For any other HVAC module DTCs, REFER to the HVAC MODULE DTC TABLE .
No : For vehicles with navigation, GO to S5.
For vehicles without navigation, GO to S6.

S5 MONITOR THE PASSENGER HEATED SEAT (CC_SW_P_HSEATS) PID AND CHECK INPUTS
- Enter the following diagnostic mode on the scan tool: DataLogger - FCIM - PIDs: CC_SW_P_HSEATS.
- Monitor the FCIM PID while pushing the passenger heated seat button.
- Do the PID states agree with the switch button positions?

Yes : GO to S6.
No : INSTALL a new FCIM . REFER to INFORMATION AND ENTERTAINMENT SYSTEMS . TEST the system for normal operation.

S6 MONITOR THE PASSENGER HEATED SEAT (CC_SW_P_HSEATS) PID AND CHECK INPUTS
- Enter the following diagnostic mode on the scan tool: DataLogger - HVAC Module - PIDs: CC_SW_P_HSEATS.
- Monitor the HVAC module PID while pushing the passenger 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.

S7 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- 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 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-3, circuit SBP18 (YE/RD), harness side and ground.
  
  Fig 1: Measuring Voltage Between Heated Seat Module C3304B-3, Circuit SBP18 (YE/RD), Harness Side & Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?

Yes : GO to S8.
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

S8 CHECK THE TEMPERATURE SENSOR OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: Heated Seat Module C3304a.
- Disconnect: Passenger Seat Cushion Heater Mat C334.
- Ignition ON.
- Measure the voltage between heated seat module C3304a-9, circuit VHS27 (WH/OG), harness side and ground.
  
  Fig 2: Measuring Voltage Between Heated Seat Module C3304A-9, Circuit VHS27 (WH/OG), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is any voltage present?

Yes : REPAIR the circuit. GO to S11 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 passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES
No : GO to S9.

S9 CHECK THE TEMPERATURE SENSOR OUTPUT CIRCUIT FOR AN OPEN AND SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between:
  - heated seat module C3304a-9, circuit VHS27 (WH/OG), harness side and seat cushion heater mat C334-3, circuit VHS27 (WH/OG), harness side.
  - heated seat module C3304a-9, circuit VHS27 (WH/OG), 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-9 and C334-3, and greater than 10,000 ohms between C3304a-9 and ground?

Yes : GO to S10.
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

S10 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 passenger seat cushion heater mat C334-4, 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 S11.
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

S11 CHECK TEMPERATURE SENSOR FOR AN OPEN
- Measure the resistance between rear heated seat cushion C334 pin 3 and pin 4, component side.
  
  Fig 5: Measuring Resistance Between Rear Heated Seat Cushion C334 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 S12.
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 passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES

S12 CHECK THE HEATER MAT OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between heated seat module C3304b-6, circuit CHS07 (GY/BU), harness side and ground.
  
  Fig 6: Measuring Voltage Between Heated Seat Module C3304B-6, Circuit CHS07 (GY/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 : GO to S13.

S13 CHECK CUSHION HEATER MAT OUTPUT CIRCUIT FOR AN OPEN AND SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between:
  - heated seat module C3304b-6, circuit CHS07 (GY/BU), harness side and passenger seat cushion heater mat C334-1, circuit CHS07 (GY/BU), harness side.
  - heated seat module C3304b-6, circuit CHS07 (GY/BU), harness side and ground.
  Fig 7: Checking Cushion Heater Mat Output Circuit For Open And Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between C3304b-6 and C334-1, and greater than 10,000 ohms between C3304b-6 and ground?

Yes : GO to S14.
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

S14 CHECK THE HEATER MAT RESISTANCE
- Connect: Passenger Seat Backrest Heater Mat C335.
- Connect: Passenger Seat Cushion Heater Mat C334.
- Measure the resistance between heated seat module C3304b-6, circuit CHS07 (GY/BU), harness side and ground.
  
  Fig 8: Measuring Resistance Between Heated Seat Module C3304B-6, Circuit CHS07 (GY/BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance between 1.2 and 4.0 ohms?

Yes : GO to S21.
No : GO to S15.

S15 CHECK THE CUSHION HEATER MAT FOR AN OPEN
- Disconnect: Passenger Seat Cushion Heater Mat C334.
- Measure the resistance between passenger seat cushion heater mat C334 pins 1 and 2, component side.
  
  Fig 9: Measuring Resistance Between Passenger Seat Cushion Heater Mat C334 Pins 1 And 2, Component Side
  Courtesy of FORD MOTOR CO.
- Is the resistance between 0.6 and 2.0 ohms?

Yes : 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 passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES
No : GO to S16.

S16 CHECK THE CIRCUIT BETWEEN THE CUSHION HEATER MAT AND BACKREST HEATER MAT FOR AN OPEN AND SHORT TO GROUND
- Disconnect: Passenger Seat Backrest Heater Mat C335.
- Measure the resistance between:
  - seat cushion heater mat C334-2, circuit CHS12 (YE/GN), harness side and seat backrest heater mat C335-1, circuit CHS12 (YE/GN), harness side.
  - seat cushion heater mat C334-2, circuit CHS12 (YE/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 S17.
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

S17 CHECK BACKREST HEATER MAT FOR AN OPEN
- Measure the resistance between passenger seat backrest heater mat C335 pins 1 and 2, component side.
  
  Fig 11: Measuring Resistance Between Passenger Seat Backrest Heater Mat C335 Pins 1 And 2, Component Side
  Courtesy of FORD MOTOR CO.
- Is the resistance between 0.6 and 2.0 ohms?

Yes : REPAIR circuit GD139 (BK/YE) for an open. 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 passenger seat backrest heater mat. 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

S18 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 C2365a.
  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-8, circuit CHS30 (GY/YE), harness side and ground.
  
  Fig 12: Measuring Voltage Between Heated Seat Module C3304A-8, Circuit CHS30 (GY/YE), 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

S19 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-8, circuit CHS30 (GY/YE), harness side and HVAC module C2356a-4, circuit CHS30 (GY/YE), 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 S20.
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

S20 CHECK THE HEATED SEAT MODULE SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between heated seat module C3304a-8, circuit CHS30 (GY/YE), harness side and ground.
  
  Fig 14: Measuring Resistance Between Heated Seat Module C3304A-8, Circuit CHS30 (GY/YE), 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

S21 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 CHS30 (GY/YE) should drop momentarily when the passenger heated seat control button is pressed.
- Measure the voltage between passenger heated seat module C3304a-8, circuit CHS30 (GY/YE), harness side and ground by back-probing the heated seat module connector. Press the passenger heated seat button on the HVAC module and note the voltage.
  
  Fig 15: Measuring Voltage Between Passenger Heated Seat Module C3304A-8, Circuit CHS30 (GY/YE), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts before pressing the passenger 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 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 passenger heated seat button was pressed, 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

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 passenger seat side air bag module C313. REPOWER the SRS . REFER to GENERAL PROCEDURES