Pinpoint Test A: The Heated Seats Are Inoperative - Driver and Passenger Seats

Seats

Pinpoint Test A: The Heated Seats are Inoperative - Driver and Passenger Seats

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 or passenger 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 appropriate (driver or passenger) heated seat relay (located in the Central Junction Box (CJB). When the heated seat relay is activated, voltage is supplied to the cushion heater mat. The cushion heater mats are directly connected to ground to complete the electrical circuit to heat the seat.

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- BCM

PINPOINT TEST A: THE HEATED SEATS ARE INOPERATIVE - DRIVER AND PASSENGER SEATS

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A1 CHECK FOR VOLTAGE TO THE DRIVER HEATED SEAT RELAY

- Disconnect: Driver Heated Seat Relay.
- Ignition ON.
- Measure the voltage between driver heated seat relay socket pin 1, circuit CBP17 (BN/GN), and ground.




- Is the voltage greater than 10 volts?

Yes
GO to A2.

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. TEST the system for normal operation. Diagrams By Number

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A2 CHECK THE HEATED SEAT SWITCH GROUND CIRCUIT

- Ignition OFF.
- Disconnect: Driver Heated Seat Switch C2400.
- Measure the resistance between driver heated switch C2400-4, circuit GD115 (BK/GY), harness side and ground.




- Is the resistance less than 5 ohms?

Yes
GO to A3.

No
REPAIR the circuit. TEST the system for normal operation.

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A3 CHECK THE BCM FOR CORRECT OPERATION

- 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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