Part 1
Seating
Pinpoint Test V: The Heated Seat is Inoperative/Does Not Operate Correctly - Driver
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
The heated seat module receives ignition voltage, battery voltage and ground. The HVAC module supplies a momentary ground signal to the heated seat module on circuit CHS29 to request the system ON or OFF. The heated seat module supplies voltage to the heater mats on circuit CHS02 and ground is supplied on circuit GD904. The cushion and backrest heater mats are connected in series and operate together. The heated seat module supplies a reference voltage to the temperature sensor on circuit VHS26 and return on RHS05.
The Front Controls Interface Module (FCIM) and the HVAC module communicate on the Controller Area Network (CAN) and PIDs are available to check heated seat switch operation in both modules.
The heated seat module faults detected will be:
- a heater feed circuit short to battery, ground or open.
- sensor circuit short to battery or open.
- heated seat switch stuck closed to ground.
The HVAC module reports the following DTCs for the driver heated seat. These DTCs are for request circuit CHS29.
- DTC B1030:11 (Left Front Seat Heater: Circuit Short To Ground)- If the driver seat request circuit from the HVAC module to the heated seat module is shorted to ground, the DTC is set.
- DTC B1030:12 (Left Front Seat Heater: Circuit Short To Battery)- If the driver seat request circuit from the HVAC module to the heated seat module is shorted to voltage, the DTC is set.
- DTC B1030:13 (Left Front Seat Heater: Circuit Open)- If the driver seat request circuit from the HVAC module to the heated seat module is open, the DTC is set.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Heater feed circuit short to battery, ground or open
- Sensor circuit short to battery, ground or open
- Heater mat
- Heated seat module
- HVAC module
- FCIM (Front Controls Interface Module)
PINPOINT TEST V : 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 switch is ON.
NOTE: The Supplemental Restraint System (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.
V1 CHECK FOR HEATED SEAT INDICATOR ILLUMINATION
- Start the engine.
- Verify system indicator illumination.
Do the driver heated seat indicators illuminate or flash and then turn off?
Yes
GO to V7.
No
GO to V2.
V2 RETRIEVE THE FCIM (Front Controls Interface Module) DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test- FCIM (Front Controls Interface Module).
Are any DTCs retrieved?
Yes
REFER to the Master DTC Chart in Body Control Systems. Master DTC Index
No
GO to V3.
V3 RETRIEVE THE HVAC MODULE DTCs
- Enter the following diagnostic mode on the scan tool: Self Test- HVAC Module.
Are any DTCs retrieved?
Yes
If DTC B1030:12, GO to V21.
If DTC B1030:13, GO to V22.
If DTC B1030:11, GO to V23.
For any other HVAC module DTCs, REFER to the HVAC Module DTC Chart. Seats
No
For vehicles with navigation, GO to V4.
For vehicles without navigation, GO to V5.
V4 MONITOR THE FCIM (Front Controls Interface Module) DRIVER HEATED SEAT (CC_SW_D_HSEATS) PID AND CHECK THE INPUTS
- Enter the following diagnostic mode on the scan tool: DataLogger- FCIM (Front Controls Interface Module)- PIDs.
- Monitor the CC_SW_D_HSEATS PID while pushing the driver heated seat button.
Do the PID states agree with the switch button positions?
Yes
INSTALL a new HVAC module. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
INSTALL a new FCIM (Front Controls Interface Module). TEST the system for normal operation.
V5 CHECK THE HVAC FUNCTIONS
NOTE: The purpose of this step is to verify the HVAC module is able to receive and process inbound command messages from the communication bus and demonstrate the HVAC module is operational. This indicates the heated seat buttons on the FCIM (Front Controls Interface Module) may not be sending the commands.
- Operate the A/C, heater and defrost using the buttons on the FCIM (Front Controls Interface Module) and check for correct HVAC function.
Does the HVAC system function correctly?
Yes
GO to V6.
No
REFER to Heating and Air Conditioning to diagnose the HVAC concern.
V6 MONITOR THE HVAC MODULE LEFT SEAT HEATER (ST_HEAT_LT) PID AND CHECK THE INPUTS
- Enter the following diagnostic mode on the scan tool: DataLogger- HVAC Module- PIDs.
- Monitor the ST_HEAT_LT 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. TEST the system for normal operation.
No
INSTALL a new FCIM (Front Controls Interface Module). TEST the system for normal operation.
V7 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- 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: Driver Seat Side Air Bag C3051.
- Disconnect: Driver Seat Safety Belt Buckle Pretensioner C3065.
- Disconnect: Passenger Seat Side Air Bag C339.
- Disconnect: Passenger Seat Safety Belt Buckle Pretensioner C3066.
- Disconnect: Heated Seat Module C359B.
- 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:
- heated seat module C359B-1, circuit CBX01 (GN//RD), harness side and ground.
- heated seat module C359B-2, circuit SBX06 (GY/RD), harness side and ground.
Are the voltages greater than 10 volts?
Yes
GO to V8.
No
VERIFY Smart Junction Box (SJB) fuse 35 (10A) and Battery Junction Box (BJB) fuse 22 (30A) are OK. If OK, REPAIR the affected circuit. If not OK, Refer to the Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation. Diagrams By Number
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
V8 CHECK THE HEATED SEAT MODULE GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure the resistance between heated seat module C359B-5, circuit GD903 (BK/WH), harness side and ground.
Is the resistance less than 5 ohms?
Yes
GO to V9.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
V9 CHECK THE HEATER MAT OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between heated seat module C359B-4, circuit CHS02 (YE/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 safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
No
GO to V10.
V10 CHECK THE HEATER MAT RESISTANCE
- Ignition OFF.
- Measure the resistance between heated seat module C359B-4, circuit CHS02 (YE/BU), harness side and ground.
- Repeat the resistance measurement between heated seat module C359B-4, circuit CHS02 (YE/BU), harness side and ground with an occupant or weight on the seat and check for an intermittent open.
Is the resistance between 1.2 and 4 ohms?
Yes
GO to V17.
No
GO to V11.
V11 CHECK THE HEATER MAT OUTPUT CIRCUIT FOR AN OPEN AND SHORT TO GROUND
- Disconnect: Driver Seat Cushion Heater Mat C364.
- Measure the resistance between:
- heated seat module C359B-4, circuit CHS02 (YE/BU), harness side and cushion heater mat C364-1, circuit CHS02 (YE/BU), harness side.
- heated seat module C359B-4, circuit CHS02 (YE/BU), harness side and ground.
Is the resistance less than 5 ohms between C359B-4 and C364-1, and greater than 10,000 ohms between C359B-4 and ground?
Yes
GO to V12.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
V12 CHECK THE CUSHION HEATER MAT FOR AN OPEN
- Measure the resistance between driver seat cushion heater mat C364 pins 1 and 4, component side.
Is the resistance between 0.6 and 2 ohms?
Yes
GO to V13.
No
INSTALL a new driver seat cushion heater mat. REFER to Seat Cushion Heater Mat - Front . TEST the system for normal operation.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
V13 CHECK THE CUSHION HEATER MAT FOR AN OPEN
- Carry out the following measurements with an occupant in the seat and check for an open heater mat with weight on the seat.
- Measure the resistance between driver seat cushion heater mat C364 pins 1 and 4, component side.
Is the resistance between 0.6 and 2 ohms?
Yes
GO to V14.
No
INSTALL a new driver seat cushion heater mat. REFER to Seat Cushion Heater Mat - Front . TEST the system for normal operation.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
V14 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 C364-4, circuit CHS01 (GY/VT), harness side and seat backrest heater mat C365-1, circuit CHS01 (GY/VT) harness side.
- seat cushion heater mat C364-4, circuit CHS01 (GY/VT), harness side and ground.
Is the resistance less than 5 ohms between C364-4 and C365-1, and greater than 10,000 ohms between C364-4 and ground?
Yes
GO to V15.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.
V15 CHECK THE BACKREST HEATER MAT FOR AN OPEN
- Measure the resistance between driver seat backrest heater mat C365 pins 1 and 2, component side.
Is the resistance between 0.6 and 2 ohms?
Yes
GO to V16.
No
INSTALL a new driver front seat backrest heater mat. REFER to Seat Backrest Heater Mat - Front . TEST the system for normal operation.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS (Supplemental Restraint System). REFER to Restraints and Safety Systems &/or Air Bag Systems.