Pinpoint Test B: The Heated Seat Is Inoperative/Does Not Operate Correctly - Driver
Seats
Pinpoint Test B: 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 system only operates when the engine is running. When the driver heated seat switch (located on the instrument panel) is activated, it supplies a ground signal to the Body Control Module (BCM). When the BCM receives the heated seat switch signal, it activates the driver heated seat relay (located in the Central Junction Box (CJB)) by grounding the relay control circuit. When the heated seat relay is activated, voltage is supplied to the driver cushion heater mat. The driver cushion heater mat is directly connected to ground to complete the electrical circuit to heat the seat.
- DTC B1034:12 (Left Front Seat Heater Element: Circuit Short To Battery) - if the driver heated seat relay drive circuit CHS02 (YE/BU) is shorted to voltage and the BCM attempts to activate the driver heated seat relay, this DTC sets and the seat fails to heat.
- DTC B1034:14 (Left Front Seat Heater Element: Circuit Short To Ground or Open) - if the driver heated seat relay drive circuit CHS02 (YE/BU) is open or shorted to ground and the BCM attempts to activate the driver heated seat relay, this DTC sets and the seat fails to heat (circuit open) or may be on at all times (circuit shorted to ground) until the ignition is turned OFF.
- DTC B115B:23 (Front Driver Seat Heater: Signal Stuck Low) - sets when the BCM detects the driver heated seat switch is active during on-demand self-test or has been active for more than 2 minutes.
This pinpoint test is intended to diagnose the following:
- Heated seat relay
- Heated seat switch
- Wiring, terminals or connectors
- Heater mat
- BCM
PINPOINT TEST B: THE HEATED SEAT IS INOPERATIVE/DOES NOT OPERATE CORRECTLY - DRIVER
NOTE: If a seat equipped with a seat mounted side air bag is being serviced, depower the Supplemental Restraint System (SRS). Refer to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
NOTE: The air bag warning lamp illuminates when the Restraints Control Module (RCM) fuse is removed and the ignition switch is ON. This is normal operation and does not indicate an SRS fault.
NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
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B1 CHECK THE BCM FOR DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - BCM.
- Is DTC B1034:12, B1034:14 or B115B:23 retrieved?
Yes
If DTC B1034:14 is present, GO to B7.
If DTC B1034:12 is present, GO to B6.
If DTC B115B:23 is present, GO to B4.
For all other BCM DTCs, REFER to the Master DTC Chart in Multifunction Electronic Modules Body Control Module (BCM).
No
GO to B2.
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B2 CHECK THE BCM DRIVER HEATED SEAT (CC_SW_D_HSEATS) PID OPERATION
- Enter the following diagnostic mode on the scan tool: DataLogger - BCM.
- While monitoring the BCM CC_SW_D_HSEATS PID, press and release the driver heated seat switch.
- Does the PID agree with the driver heated switch status?
Yes
GO to B9.
No
GO to B3.
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B3 CHECK THE DRIVER HEATED SEAT SWITCH GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Driver Heated Seat Switch C2400.
- Measure the resistance between driver heated seat switch C2400-4, circuit GD115 (BK/GY), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to B4.
No
REPAIR the circuit. TEST the system for normal operation.
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B4 CHECK THE BCM DRIVER HEATED SEAT (CC_SW_D_HSEATS) PID OPERATION
- Ignition OFF.
- Disconnect: Driver Heated Seat Switch C2400.
- Connect a fused jumper wire between driver heated seat switch C2400-4, circuit GD115 (BK/GY), harness side and driver heated seat switch C2400-1, circuit CHS32 (BN), harness side.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - BCM.
- Observe the BCM CC_SW_D_HSEATS PID status.
- Remove the fused jumper wire.
- Observe the BCM CC_SW_D_HSEATS PID status.
- Did the PID state change when the fused jumper wire was removed?
Yes
INSTALL a new driver heated seat switch. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
GO to B5.
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B5 CHECK THE DRIVER HEATED SWITCH SIGNAL CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Ignition OFF.
- Disconnect: BCM C2280G.
- Measure the resistance between driver heated seat switch C2400-1, circuit CHS32 (BN), harness side and BCM C2280G-8, harness side; and between driver heated seat switch C2400-1, circuit CHS32 (BN), harness side and ground.
- Is the resistance less than 5 ohms between the heated seat switch and the BCM; and greater than 10,000 ohms between the heated seat switch and ground?
Yes
GO to B13.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B6 CHECK THE RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Driver Heated Seat Relay.
- Ignition ON.
- Measure the voltage between driver heated seat relay socket pin 2, circuit CHS02 (YE/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.
No
INSTALL a new driver heated seat relay. RECONNECT all connectors and REPEAT the self-test. If the DTC is retrieved again, GO to B13.
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B7 CHECK THE RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Driver Heated Seat Relay.
- Disconnect: BCM C2280D.
- Measure the resistance between driver heated seat relay socket pin 2, circuit CHS02 (YE/BU), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to B8.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B8 CHECK THE RELAY CONTROL CIRCUIT FOR AN OPEN
- Measure the resistance between driver heated seat relay socket pin 2, circuit CHS02 (YE/BU), harness side and BCM C2280D-10, circuit CHS02 (YE/BU), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new driver heated seat relay. RECONNECT all connectors and REPEAT the self-test. If the DTC is retrieved again, GO to B13.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B9 CHECK FOR VOLTAGE TO THE DRIVER HEATED SEAT RELAY
- Ignition OFF.
- Disconnect: Driver Heated Seat Relay.
- Ignition ON.
- Measure the voltage between driver heated seat relay socket pin 1, circuit CBP17 (BN/GN) and ground; and between driver heated seat relay socket pin 3, circuit CBP17 (BN/GN) and ground.
- Is the voltage greater than 10 volts for both measurements?
Yes
GO to B10.
No
VERIFY Central Junction Box (CJB) fuse 17 (7.5A) is OK. If OK, REPAIR the circuit. 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
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B10 CHECK THE HEATER MAT CIRCUIT FOR VOLTAGE
- Ignition OFF.
- Connect: Driver Heated Seat Relay.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Driver Seat Side Air Bag Module C367.
- Disconnect: Driver Seat Cushion Heater C364.
- 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 Battery Disconnect.
- Start the engine.
- Activate the driver heated seat switch and measure the voltage between driver seat cushion heater C364-1, circuit CHS11 (VT/GN), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to B12.
No
GO to B11.
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B11 CHECK THE HEATER CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Driver Heated Seat Relay.
- Measure the resistance between driver heated seat relay socket pin 5, circuit CHS11 (VT/GN), harness side and driver seat cushion heater C364-1, circuit CHS11 (VT/GN), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to B14.
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 side air bag module C367.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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B12 CHECK THE HEATER MAT GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure the resistance between driver seat cushion heater C364-2, circuit GD143 (BK/VT), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
CHECK for loose or damaged connector pins and wiring damage. If OK, INSTALL a new driver seat cushion heater mat. REFER to Seat Cushion - Front Seat Cushion - Front. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C367.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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 side air bag module C367.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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B13 CHECK THE BCM FOR CORRECT OPERATION
- Ignition OFF.
- Disconnect all of the BCM connectors.
- Check for:
- corrosion.
- pushed-out pins.
- Connect all of the BCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new BCM. REFER to Multifunction Electronic Modules Body Control Module (BCM). TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B14 CHECK THE BCM FOR CORRECT OPERATION
- Ignition OFF.
- Disconnect all of the BCM connectors.
- Check for:
- corrosion.
- pushed-out pins.
- Connect all of the BCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new BCM. REFER to Multifunction Electronic Modules Body Control Module (BCM). TEST the system for normal operation.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C367.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
DISCONNECT the battery ground cable. CONNECT driver seat side air bag module C367.
REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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