Pinpoint Test H: The Heated Seat is Inoperative/Does Not Operate Correctly - Passenger
Seats
Pinpoint Test H: The Heated Seat is Inoperative/Does Not Operate Correctly - Passenger
Normal Operation
When the engine is running and the heated seat button is pressed, the Front Controls Interface Module (FCIM) illuminates the heated seat indicator and transmits a system request message to the HVAC module on the module communication network. The HVAC module receives the message and provides ground to the heated seat relay coil circuit CHS30 (GY/YE) to operate the heated seat. Voltage is supplied to the heated seat relay coil circuit CBP43 (GY) and relay contact circuit SBB16 (VT/RD). The relay energizes and supplies voltage to the cushion heater mat on circuit CHS07 (GY/BU). The cushion and backrest heater mats are connected in series by circuit CHS06 (BU/BN) and ground is supplied to the backrest heater mat circuit GD139 (BK/YE), completing the circuit to heat the seat.
The heated seat switch can be checked using a scan tool to monitor the FCIM (Front Controls Interface Module) PID.
The HVAC module reports the following DTCs for the passenger heated seat relay coil circuit CHS30 (GY/YE):
- DTC B1032:11 (Right Front Seat Heater Circuit Short To Ground)- If the passenger heated seat relay coil circuit from the HVAC module is shorted to ground, the DTC is set and the seat will heat while the system is off.
- DTC B1032:12 (Right Front Seat Heater Circuit Short To Battery)- If the passenger heated seat relay coil circuit from the HVAC module is shorted to voltage, the DTC is set and the seat will not heat.
- DTC B1032:13 (Right Front Seat Heater Circuit Open)- If the passenger heated seat relay coil circuit from the HVAC module is open, the DTC is set and the seat will not heat.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Heated seat relay
- Cushion heater mat
- Backrest heater mat
- FCIM (Front Controls Interface Module)
- HVAC module
PINPOINT TEST H : THE HEATED SEAT IS INOPERATIVE/DOES NOT OPERATE CORRECTLY - PASSENGER
NOTICE: Do not install a new heater mat on a front passenger seat cushion. Install a new Occupant Classification System (OCS) service kit. Failure to follow this instruction can cause incorrect OCS (Occupant Classification System) system operation. Refer to Restraints and Safety Systems &/or Air Bag Systems for the Occupant Classification Sensor Removal and Installation procedure.
H1 CHECK THE HEATED SEAT INDICATOR
- Start the engine.
- Operate the heated seat.
Does the heated seat indicator operate correctly?
Yes
GO to H3.
No
If the indicator illuminates but does not remain on, GO to H2.
If no indicator illumination and other FCIM (Front Controls Interface Module) functions are inoperative, REFER to Accessories and Optional Equipment to diagnose the inoperative system(s).
Otherwise, INSTALL a new FCIM (Front Controls Interface Module).
H2 RETRIEVE HVAC MODULE DTCs
- Enter the following diagnostic mode on the scan tool: Self Test- HVAC module.
Are DTCs present?
Yes
If DTC B1032:12, GO to H9.
If DTC B1032:13, GO to H10.
If DTC B1032:11, GO to H11.
For other DTCs, REFER to HVAC Module DTC Chart Seats.
No
GO to H3.
H3 CHECK FOR VOLTAGE TO THE HEATED SEAT RELAY
- Ignition OFF.
- Depower the SRS (Supplemental Restraint System). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Restraints and Safety Systems &/or Air Bag Systems.
- Disconnect: Passenger Seat Side Air Bag C337.
- Disconnect: Passenger Heated Seat Relay.
- 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.
- Ignition ON.
- Measure the voltage between:
- passenger heated seat relay socket pin 3, circuit SBB16 (VT/RD) and ground.
- passenger heated seat relay socket pin 1, circuit CBP43 (GY) and ground.
Are the voltages greater than 10 volts?
Yes
GO to H4.
No
VERIFY Battery Junction Box (BJB) fuse 16 (20A) and Smart Junction Box (SJB) 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 [1][2]Diagrams By Number. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
H4 CHECK THE HEATER CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure the resistance between passenger heated seat relay socket pin 5, circuit CHS07 (GY/BU), harness side and ground.
Is the resistance between 2 and 4 ohms?
Yes
INSTALL a new heated seat relay. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
No
GO to H5.
H5 CHECK THE CUSHION HEATER MAT CIRCUIT FOR AN OPEN
- Disconnect: Passenger Cushion Heater Mat C334.
- Measure the resistance between passenger heated seat relay socket pin 5, circuit CHS07 (GY/BU) and passenger cushion heater mat C334-1, circuit CHS07 (GY/BU), harness side.
Is the resistance less than 5 ohms?
Yes
GO to H6.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
H6 CHECK THE CUSHION HEATER MAT FOR AN OPEN
- Measure the resistance between passenger cushion heater mat C334 pins 1 and 2, component side.
Is the resistance between 1.0 and 1.5 ohm?
Yes
GO to H7.
No
INSTALL a new passenger cushion heater mat. REFER to Seat Cushion Heater Mat . TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
H7 CHECK THE GROUND CIRCUIT FOR AN OPEN
- Disconnect: Passenger Backrest Heater Mat C335.
- Measure the resistance between backrest heater mat C335-2, circuit GD139 (BK/YE), harness side and ground.
Is the resistance less than 5 ohms?
Yes
GO to H8.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
H8 CHECK THE BACKREST HEATER MAT FOR AN OPEN
- Measure the resistance between backrest heater mat C335 pins 1 and 2, component side.
Is the resistance between 1.0 and 1.5 ohm?
Yes
REPAIR circuit CHS06 (BU/BN). TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
No
INSTALL a new backrest heater mat. REFER to Seat Backrest Heater Mat . TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
H9 CHECK THE HEATED SEAT RELAY COIL CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Depower the SRS (Supplemental Restraint System). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Restraints and Safety Systems &/or Air Bag Systems.
- Disconnect: Passenger Seat Side Air Bag C337.
- Disconnect: Passenger Heated Seat Relay.
- 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.
- Ignition ON.
- Measure the voltage between passenger heated seat relay socket pin 2, circuit CHS30 (GY/YE), harness side and ground.
Is any voltage present?
Yes
REPAIR the circuit. REPEAT the self-test. CLEAR the DTCs. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
No
INSTALL a new heated seat relay. REPEAT the self-test. CLEAR the DTCs. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
H10 CHECK THE HEATED SEAT RELAY COIL CIRCUIT FOR AN OPEN
- Ignition OFF.
- Depower the SRS (Supplemental Restraint System). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Restraints and Safety Systems &/or Air Bag Systems.
- Disconnect: Passenger Seat Side Air Bag C337.
- Disconnect: Passenger Heated Seat Relay.
- Disconnect HVAC Module C294A.
- Measure the resistance between passenger heated seat relay socket pin 2, circuit CHS30 (GY/YE), harness side and HVAC module C294A-10, circuit CHS30 (GY/YE), harness side.
Is the resistance less than 5 ohms?
Yes
INSTALL a new heated seat relay. REPEAT the self-test. CLEAR the DTCs. TEST the system for normal operation.
CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
No
REPAIR the circuit. REPEAT the self-test. CLEAR the DTCs. TEST the system for normal operation.
CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
H11 CHECK THE HEATED SEAT RELAY COIL CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Depower the SRS (Supplemental Restraint System). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Restraints and Safety Systems &/or Air Bag Systems.
- Disconnect: Passenger Seat Side Air Bag C337.
- Disconnect: Passenger Heated Seat Relay.
- Measure the resistance between passenger heated seat relay socket pin 2, circuit CHS30 (GY/YE), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new heated seat relay. REPEAT the self-test. CLEAR the DTCs. TEST the system for normal operation.
CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
No
REPAIR the circuit. REPEAT the self-test. CLEAR the DTCs. TEST the system for normal operation.
CONNECT passenger seat side air bag module C337.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.