Pinpoint Test C: The Heated Seat is Inoperative/Does Not Operate Correctly - Driver
Seats
Pinpoint Tests
Pinpoint Test C: The Heated Seat is Inoperative/Does Not Operate Correctly - Driver
Refer to Wiring Diagram Set 119 (Escape/Mariner, Escape Hybrid/Mariner Hybrid), Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
Voltage is supplied from Smart Junction Box (SJB) circuit CBP43 to the heated seat relay coil. When the heated seat switch button is pressed, the HVAC module supplies ground to the driver heated seat relay coil on circuit CHS29. When the driver heated seat relay is energized, battery voltage is supplied from SJB circuit SBP18 to driver heater mat circuit CHS11. The driver heater mats are directly connected to ground circuit GD182 (BK/GY) completing the electrical circuit to heat the seat.
On vehicles equipped with navigation, the Front Controls Interface Module (FCIM) communicates the heated seat system on/off requests to the HVAC module using the communication network. The following is required for heated seat system operation:
- The engine must be running (except Hybrid).
- The HVAC module must be communicating correctly.
- If equipped with navigation, the FCIM must be communicating correctly.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Heated seat relay
- Heater mat
- FCIM (vehicles with navigation)
- HVAC module
PINPOINT TEST C: THE HEATED SEAT IS INOPERATIVE/DOES NOT OPERATE CORRECTLY - DRIVER
NOTE: The air bag warning indicator illuminates when the correct Restraints Control Module (RCM) fuse is removed and the ignition 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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C1 CHECK FOR HEATED SEAT INDICATOR ILLUMINATION
- Operate the driver heated seat and check the indicator for correct illumination.
- Does the heated seat indicator illuminate correctly?
Yes
If equipped with navigation, GO to C2.
If not equipped with navigation, GO to C3.
No
VERIFY the climate control system is operating correctly. REFER to Heating and Air Conditioning to diagnose the inoperative climate control system.
If equipped with navigation and the indicator does not illuminate, GO to C2.
If equipped with navigation and the indicator briefly illuminates but does not remain on, GO to C3.
If not equipped with navigation, INSTALL a new HVAC module. TEST the system for normal operation.
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C2 CHECK THE FCIM FOR COMMUNICATION WITH THE SCAN TOOL AND RETRIEVE DTCs
- Enter the following diagnostic mode on the scan tool: Self Test - FCIM.
- Does the FCIM communicate with the scan tool and are any DTCs present?
Yes
REFER to the Front Controls Interface Module (FCIM) DTC Chart in Accessories and Optional Equipment for diagnosis. Front Controls Interface Module (FCIM) DTC Chart
No
If the FCIM communicates with the scan tool and the heated seat indicator illuminates correctly, GO to C3.
If the FCIM communicates with the scan tool but heated seat indicators do not illuminate correctly, INSTALL a new FCIM. REFER to Accessories and Optional Equipment. TEST the system for normal operation.
If the FCIM does not communicate with the scan tool, REFER to Information Bus for diagnosis.
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C3 RETRIEVE HVAC MODULE DTCs
- Enter the following diagnostic mode on the scan tool: Self Test - HVAC Module.
- Are any DTCs present?
Yes
If DTC B12AB or B1030:12 is present, GO to C4.
If DTC B12AC or B1030:14 is present, GO to C5.
For any other DTC, REFER to the HVAC Module DTC Chart for diagnosis. Diagnostic Trouble Code Tests and Associated Procedures
No
GO to C7.
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C4 CHECK THE DRIVER HEATED SEAT REQUEST CIRCUIT FOR A 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. Supplemental Restraint System (SRS) Depowering and Repowering
- Disconnect: Driver Seat Side Air Bag C367.
- Disconnect: Driver Safety Belt Buckle Pretensioner C3201.
- Disconnect: HVAC Module C2357A or C2356B (C2356A hybrid).
- Disconnect: Driver Heated Seat Relay C3253.
- 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 driver heated seat relay C3253-3 circuit CHS29 (WH/BU), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
No
INSTALL a new driver heated seat relay. RECONNECT all connectors and REPEAT the self-test. If the DTC is retrieved again, INSTALL a new HVAC module. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
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C5 CHECK THE DRIVER HEATED SEAT REQUEST CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Restraint Systems. Supplemental Restraint System (SRS) Depowering and Repowering
- Disconnect: Driver Seat Side Air Bag C367.
- Disconnect: Driver Safety Belt Buckle Pretensioner C3201.
- Disconnect: Driver Heated Seat Relay C3253.
- Disconnect: HVAC Module C2357A or C2356B (C2356A hybrid).
- Measure the resistance between driver heated seat relay C3253-3, circuit CHS29 (WH/BU), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to C6.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
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C6 CHECK THE DRIVER HEATED SEAT REQUEST CIRCUIT FOR AN OPEN
- For vehicles equipped with manual temperature control, measure the resistance between driver heated seat relay C3253-3, circuit CHS29 (WH/BU), harness side and HVAC module C2357A-1, circuit CHS29 (WH/BU), harness side.
- For hybrid vehicles, measure the resistance between driver heated seat relay C3253-3, circuit CHS29 (WH/BU), harness side and HVAC module C2356A-5, circuit CHS29 (WH/BU), harness side.
- For non-hybrid vehicles equipped with automatic temperature control, measure the resistance between driver heated seat relay C3253-3, circuit CHS29 (WH/BU), harness side and HVAC module C2356B-6, circuit CHS29 (WH/BU), harness side.
- Is the resistance less than 5 ohms?
Yes
CHECK the relay and HVAC module electrical connectors and pins for damage. REPAIR as necessary. RECONNECT the connectors. REPEAT the self-test. If the DTC is retrieved again, INSTALL a new HVAC module. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
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C7 CHECK THE HEATER CIRCUIT FOR VOLTAGE
- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Restraint Systems. Supplemental Restraint System (SRS) Depowering and Repowering
- Disconnect: Driver Seat Side Air Bag C367.
- Disconnect: Driver Safety Belt Buckle Pretensioner C3201.
- Disconnect: Driver Cushion Heater Mat C3283.
- 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.
- Start the engine.
- Press the driver heated seat switch on and measure the voltage between driver cushion heater mat C3283-2, circuit CHS11 (VT/GN), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to C11.
No
GO to C8.
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C8 CHECK THE HEATED SEAT RELAY
- Ignition OFF.
- Disconnect: Driver Heated Seat Relay C3283.
- Install a test relay in the driver heated seat relay socket.
- Start the engine.
- Press the driver heated seat switch on and measure the voltage between driver cushion heater mat C3283-2, circuit CHS11 (VT/GN), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
INSTALL a new heated seat relay. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
No
DISCONNECT the test relay and GO to C9.
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C9 CHECK FOR VOLTAGE TO THE DRIVER HEATED SEAT RELAY
- Measure the voltage between:
- driver heated seat relay C3253-5, circuit SBP18 (YE/RD), harness side and ground.
- driver heated seat relay C3253-1, circuit CBP43 (GY), harness side and ground.
- Are the voltages greater than 10 volts?
Yes
GO to C10.
No
VERIFY Smart Junction Box (SJB) fuses 18 (20A) and 43 (10A) are OK. If OK, REPAIR the circuit(s). If not OK, Refer to the Wiring Diagrams to identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation. Diagrams By Number
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
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C10 CHECK THE HEATER CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure the resistance between driver heated seat relay C3253-4, circuit CHS11 (VT/GN), harness side and driver cushion heater mat C3283-2, circuit CHS11 (VT/GN), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new HVAC module. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
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C11 CHECK THE HEATER GROUND CIRCUIT FOR AN OPEN
- Measure the resistance between driver cushion heater mat C3283-1, circuit GD182 (BK/GY), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to C12.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
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C12 CHECK THE BACKREST HEATER MAT FOR AN OPEN
- Disconnect: Driver Backrest Heater Mat Electrical Connector.
- Measure the resistance between driver backrest heater mat electrical connector pins 1 and 2, component side.
- Is the resistance between 0.8 and 1.5 ohms?
Yes
INSTALL a new cushion heater mat. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
No
INSTALL a new backrest heater mat. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat safety belt buckle pretensioner C3201 and driver seat side air bag C367.
REPOWER the SRS. REFER to Restraint Systems.
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