Pinpoint Test V: The Heated Seats are Inoperative - Rear
Seats
Pinpoint Tests
Pinpoint Test V: The Heated Seats are Inoperative - Rear
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
The heated seat module receives battery voltage on circuit SBB07 (WH/RD) and ignition voltage on circuit CBP35 (YE/GY), and is supplied ground on circuit GD133 (BK). When the left rear heated seat control switch is pressed with the ignition switch in RUN or START, a ground is supplied on circuit CHS46 (YE/GN) to command the system ON or OFF in hi heat mode or circuit CHS47 (VT/GN) to command the system ON or OFF in low heat mode. When the right rear heated seat control switch is pressed with the ignition switch in RUN or START, a ground is supplied on circuit CHS50 (BU/GY) to command the system ON or OFF in hi heat mode or circuit CHS51 (YE/GY) to command the system ON or OFF in low heat mode. When commanded ON, voltage is supplied to the heated seat switch from the heated seat module on either circuit CHS48 (YE) (left rear) or CHS52 (BU) (right rear) (hi heat mode); or circuit CHS49 (VT) (left rear) or CHS53 (WH/BN) (right rear) (low heat mode) illuminating the switch indicator. The heated seat module also supplies voltage to the cushion and backrest heater mats on circuit CHS39 (GN/BU) (left rear) or CHS43 (GY/BU) (right rear) and ground to the heater mats on circuit GD126 (BK/WH) (left rear) or GD151 (BK/GN) (right rear). The cushion and backrest heater mats are connected in series and operate together. Temperature is maintained by the heated seat module using a sensor contained within the cushion heater mat. The heated seat module monitors the temperature sensors on circuit VHS42 (GN) (left rear) or VHS45 (GY/BN) (right rear) for adjusting the current flow to the heater mats and uses a ground supplied on circuit RHS41 (GN/BN). The heated seat module is designed to remain ON, heating the seat and maintaining temperature until switched OFF or the ignition voltage is switched OFF.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Heated seat module
PINPOINT TEST V: THE HEATED SEATS ARE INOPERATIVE - REAR
WARNING: Never install heated seat parts not intended for use on this vehicle. Parts released for other model years or vehicle lines are not compatible even if they appear visually and physically similar. Installing incorrect parts will result in heated seat system performance outside design specification. Failure to follow this instruction may result in serious personal injury.
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V1 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- Disconnect: Heated Seat Module C3162.
- Ignition ON.
- Measure the voltage between:
- heated seat module C3162-2, circuit CBP35 (YE/GY), harness side and ground.
- heated seat module C3162-1, circuit SBB07 (WH/RD), harness side and ground.
- Are the voltages greater than 10 volts?
Yes
GO to V2.
No
VERIFY Battery Junction Box (BJB) fuse 7 (30A) and Smart Junction Box (SJB) fuse 35 (10A) are OK. If OK, REPAIR the affected circuit. If not OK, Refer to the Wiring Diagrams to identify possible causes of the circuit short. TEST the system for normal operation. Diagrams By Number
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V2 CHECK THE HEATED SEAT MODULE GROUND
- Ignition OFF.
- Measure the resistance between heated seat module C3162-7, circuit GD133 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to V3.
No
REPAIR the circuit. TEST the system for normal operation.
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V3 CHECK THE SENSOR RETURN CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between heated seat module C3162-13, circuit RHS41 (GN/BN), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit. TEST the system for normal operation.
No
GO to V4.
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V4 CHECK THE SENSOR RETURN CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between heated seat module C3162-13, circuit RHS41 (GN/BN), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to V5.
No
REPAIR the circuit. TEST the system for normal operation.
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V5 CHECK THE SENSOR RETURN CIRCUIT FOR AN OPEN
- Disconnect: Right Rear Heated Seat C3169.
- Measure the resistance between heated seat module C3162-13, circuit RHS41 (GN/BN), harness side and right rear heated seat C3169-3, circuit RHS41 (GN/BN), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new heated seat module. REFER to Heated Seat Module - Rear Seat Heated Seat Module - Rear Seat. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
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