Pinpoint Test S: The Heated Seat Is Inoperative - Passenger
Seats
Pinpoint Tests
Pinpoint Test S: The Heated Seat is Inoperative - Passenger
Refer to Wiring Diagram Set 119 (Fusion/Milan/MKZ, Fusion Hybrid/Milan Hybrid), Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
The heated seat module receives battery voltage on circuit SBP18. The HVAC module supplies a momentary ground signal to the heated seat module on circuit CHS30 to request the system on/off. The heated seat module supplies voltage to the heater mats on circuit CHS07 and ground is supplied on circuit GD139. The heated seat module monitors the temperature sensor on circuit VHS27. If the temperature sensor circuits open, the heated seat module will disable output voltage to the heater mat. The heated seat module control circuits are monitored by the HVAC module and will set a DTC if a circuit fault is detected.
The Front Controls Interface Module (FCIM) (with navigation), HVAC module and heated seat module must be communicating correctly for the system to operate correctly. PIDs are available to check heated seat switch operation in the FCIM (with navigation) and HVAC module (with and without navigation).
Normal heat cycle may require several minutes to initially warm the seat. The seat should be occupied to correctly test for normal operation. Temperature measuring devices do not provide an accurate method for testing heated seat operation as surface temperatures are subject to human and environmental characteristics. Correct testing requires heater mat resistance measurements which have tight tolerances affecting the length of time for the heater mats to reach maximum operating temperature.
- DTC B1032:12 (Right Front Seat Heater: Circuit Short To Battery) - If the passenger seat control circuit from the HVAC module to the heated seat module is shorted to voltage, the DTC is set in the HVAC module.
- DTC B1032:14 (Right Front Seat Heater: Circuit Short To Ground or Open) - If the passenger seat control circuit from the HVAC module to the heated seat module is shorted to ground or open, the DTC is set in the HVAC module.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Heater feed circuit short to battery, ground or open
- Sensor circuit short to battery, ground or open
- Heated seat switch stuck closed to ground
- Heater mat
- Heated seat module
- HVAC module
- FCIM (if equipped)
PINPOINT TEST S: THE HEATED SEAT IS INOPERATIVE - PASSENGER
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.
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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 Chart to diagnose the heated seats are inoperative - driver and front passenger or the heated seat is inoperative/does not operate correctly - driver. Symptom Related Diagnostic Procedures
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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.
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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 Chart in Body Control Systems. Diagnostic Trouble Code (DTC) Chart
No
GO to S4.
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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 Chart. HVAC Module DTC Chart
No
For vehicles with navigation, GO to S5.
For vehicles without navigation, GO to S6.
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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 Accessories and Optional Equipment. TEST the system for normal operation.
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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. TEST the system for normal operation.
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S7 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the
General Procedures portion of Restraint Systems.
- 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.
- Measure the voltage between heated seat module C3304b-3, circuit SBP18 (YE/RD), harness side and ground.
- 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 Restraint Systems.
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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.
- 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 Seat Cushion Cover - Front.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C313. REPOWER the SRS. REFER to Restraint Systems.
No
GO to S9.
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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.
- 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 Restraint Systems.
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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.
- 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 Restraint Systems.
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S11 CHECK TEMPERATURE SENSOR FOR AN OPEN
- Measure the resistance between rear heated seat cushion C334 pin 3 and pin 4, component side.
- 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 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 Restraint Systems.
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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.
- 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 Restraint Systems.
No
GO to S13.
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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.
- 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 Restraint Systems.
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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.
- Is the resistance between 1.2 and 4.0 ohms?
Yes
GO to S21.
No
GO to S15.
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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.
- Is the resistance between 0.6 and 2.0 ohms?
Yes
GO to S16.
No
INSTALL a new driver seat cushion heater mat. REFER to Seat Cushion Cover - Front 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 Restraint Systems.
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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.
- 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 Restraint Systems.
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S17 CHECK BACKREST HEATER MAT FOR AN OPEN
- Measure the resistance between passenger seat backrest heater mat C335 pins 1 and 2, component side.
- 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 Restraint Systems.
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 Restraint Systems.
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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 in the
General Procedures portion of Restraint Systems.
- 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.
- Ignition ON.
- Measure the voltage between heated seat module C3304a-8, circuit CHS30 (GY/YE), harness side and ground.
- 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 Restraint Systems.
No
INSTALL a new HVAC 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 Restraint Systems.
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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 in the
General Procedures portion of Restraint Systems.
- 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.
- 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.
- 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 Restraint Systems.
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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.
- Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new heated seat module. REFER to Heated Seat Module 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 Restraint Systems.
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 Restraint Systems.
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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.
- 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 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 Restraint Systems.
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. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C313. REPOWER the SRS. REFER to Restraint Systems.
If voltage is less than 10 volts, INSTALL a new heated seat module. REFER to Heated Seat Module 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 Restraint Systems.
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