Pinpoint Test T: The Heated Seat Is Inoperative - Right Rear
Seats
Pinpoint Tests
Pinpoint Test T: The Heated Seat is Inoperative - Right Rear
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
The Battery Junction Box (BJB) supplies battery voltage to the heated seat module on circuit SBP18 (YE/RD), ignition voltage is supplied from the Smart Junction Box (SJB) on circuit CPB35 (YE/GY) and ground on circuit GD145 (BK/BU). When the heated seat control switch is pressed, a ground signal is sent to the heated seat module to command the system ON or OFF in HI heat mode or LOW heat mode. When commanded ON, a ground signal is supplied from the heated seat switch to the heated seat module on either circuit CHS48 (YE) (HI heat mode) or CHS49 (VT) (LO 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) and ground to the heater mats on circuit GD145 (BK/BU). 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 supplies a reference voltage to the temperature sensor on circuit VHS42 (GN) and monitors the temperature sensor for adjusting the current flow to the heater mats. The heated seat module is designed to remain ON, heating the seat and maintaining temperature until switched OFF.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Heater mat
- Heated seat switch
- Heated seat module
PINPOINT TEST T: THE HEATED SEAT IS INOPERATIVE - RIGHT REAR
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T1 CHECK THE HEATED SEAT OPERATION
- Ignition ON.
- Operate the right rear heated seat switch.
- Does the seat operate in either setting?
Yes
If only the low setting operates, GO to T15.
If only the high setting operates, GO to T16.
No
GO to T2.
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T2 CHECK THE HEATED SEAT SWITCH INPUT
- Disconnect: Heated Seat Module C3054A.
- Measure the resistance between heated seat module C3054A-8, circuit CHS50 (BU/GY), harness side and ground while pressing the heated seat switch to high.
- Is the resistance less than 30 ohms when the heated seat switch is pressed and greater than 10,000 ohms when the heated seat switch is not pressed?
Yes
GO to T4.
No
GO to T3.
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T3 CHECK THE HEATED SEAT SWITCH GROUND CIRCUIT FOR AN OPEN
- Disconnect: Right Rear Heated Seat Switch C3182.
- Measure the resistance between right rear heated seat switch C3182-1, circuit GD143 (BK/VT), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to T17.
No
REPAIR the circuit. TEST the system for normal operation.
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T4 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- Disconnect: Heated Seat Module C3054B.
- Measure the voltage between heated seat module C3054B-3, circuit SBP18 (YE/RD), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to T5.
No
REPAIR the circuit. TEST the system for normal operation.
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T5 CHECK THE HEATER MATS RESISTANCE AND HEATER MAT CIRCUITS FOR AN OPEN
- Measure the resistance between heated seat module C3054B-6, circuit CHS43 (GY/BU), harness side and ground.
- Is the resistance between 3 and 5 ohms?
Yes
GO to T11.
No
GO to T6.
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T6 CHECK THE HEATER MATS GROUND CIRCUIT FOR AN OPEN
- Disconnect: Right Rear Seat Backrest Heater Mat C3362.
- Measure the resistance between passenger backrest heater mat C3362-2, circuit GD150 (BK/WH), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to T7.
No
REPAIR the circuit. TEST the system for normal operation.
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T7 CHECK RIGHT REAR HEATER INPUT CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect: Rear Seat Cushion C3363.
- Measure the resistance between:
- heated seat module C3054B-6, circuit CHS43 (GY/BU), harness side and right rear seat cushion heater mat C3363B-1, circuit CHS43 (GY/BU), harness side.
- heated seat module C3054B-6, circuit CHS43 (GY/BU), harness side and ground.
- Is the resistance less than 5 ohms between C3054B-6 and C3363-1, and greater than 10,000 ohms between C3054B-6 and ground?
Yes
GO to T8.
No
REPAIR the circuit. TEST the system for normal operation.
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T8 CHECK THE CUSHION HEATER MAT FOR AN OPEN
- Measure the resistance between rear heated seat cushion C3363 pins 1 and 4, component side.
- Is the resistance between 0.7 and 1.5 ohms?
Yes
GO to T9.
No
INSTALL a new rear seat cushion heater mat. REFER to Seat Cushion Heater Mat Seat Cushion Heater Mat. TEST the system for normal operation.
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T9 CHECK THE CIRCUIT BETWEEN THE CUSHION AND BACKREST HEATER MATS FOR AN OPEN OR SHORT TO GROUND
- Measure the resistance between:
- right rear seat cushion heater mat C3363-4, circuit CHS44 (GN/VT), harness side and right rear seat backrest heater mat C3362-1, circuit CHS44 (GN/VT), harness side.
- right rear seat cushion heater mat C3363-4, circuit CHS44 (GN/VT), harness side and ground.
- Is the resistance less than 5 ohms between C3363-4 and C3362-1, and greater than 10,000 ohms between C3363-4 and ground?
Yes
GO to T10.
No
REPAIR the circuit. TEST the system for normal operation.
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T10 CHECK THE BACKREST HEATER MAT FOR AN OPEN
- Measure the resistance between right rear seat backrest heater C3362 pins 1 and 2, component side.
- Is the resistance between 0.7 and 1.5 ohms?
Yes
GO to T11.
No
INSTALL a new rear seat backrest heater mat. REFER to Seat Backrest Heater Mat Seat Backrest Heater Mat. TEST the system for normal operation.
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T11 CHECK THE TEMPERATURE SENSOR CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between heated seat module C3054A-9, circuit VHS45 (GY/BN), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit. GO to T14 to check the temperature sensor for damage. If temperature sensor is OK, TEST the system for normal operation.
No
GO to T12.
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T12 CHECK THE TEMPERATURE SENSOR CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between heated seat module C3054A-9, circuit VHS45 (GY/BN), harness side and ground.
- Is the resistance greater than 10,000?
Yes
GO to T13.
No
REPAIR circuit VHS45 (GY/BN). TEST the system for normal operation.
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T13 CHECK THE TEMPERATURE SENSOR CIRCUITS FOR AN OPEN OR SHORT TO GROUND
- Measure the resistance between:
- heated seat module C3054A-9, circuit VHS45 (GY/BN), harness side and C3054A-12, circuit RHS41 (BK/BU), harness side.
- heated seat module C3054A-9, circuit VHS45 (GY/BN), harness side and ground.
- Is the resistance greater than 300 and less than 300,000 ohms between C3054A-3 and C3054A-12 and greater than 10,000 ohms between C3054A-12 and ground?
Yes
INSTALL a new heated seat module. REFER to Heated Seat Module - Second Row Heated Seat Module - Second Row. TEST the system for normal operation.
No
GO to T14.
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T14 CHECK THE TEMPERATURE SENSOR FOR AN OPEN
- Disconnect: Right Rear Seat Cushion C3363.
- Measure the resistance between rear heated seat cushion C3363 pin 2 and pin 3, component side.
- Is the resistance between 8,000 ohms and 15,000 ohms?
Yes
REPAIR circuit RHS41 (GN/BU) or VHS45 (GY/BN). TEST the system for normal operation.
No
INSTALL a new rear seat cushion heater mat. REFER to Seat Cushion Heater Mat Seat Cushion Heater Mat. TEST the system for normal operation.
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T15 CHECK THE HEATED SEAT SWITCH HIGH CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect: Heated Seat Switch C3182.
- Measure the resistance between:
- heated seat module C3054A-8, circuit CHS50 (BU/GY), harness side and right rear heated seat switch C3182-6, circuit CHS50 (BU/GY), harness side.
- heated seat module C3054A-8, circuit CHS50 (BU/GY), harness side and ground.
- Is the resistance less than 5 ohms between the heated seat module and the heated seat switch and greater than 10,000 ohms between the heated seat module and ground?
Yes
GO to T17.
No
REPAIR the circuit. TEST the system for normal operation.
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T16 CHECK THE HEATED SEAT SWITCH LOW CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect: Heated Seat Switch C3182.
- Measure the resistance between:
- heated seat module C3054A-7, circuit CHS51 (YE/GY), harness side and right rear heated seat switch C3182-2, circuit CHS51 (YE/GY), harness side.
- heated seat module C3054A-7, circuit CHS51 (YE/GY), harness side and ground.
- Is the resistance less than 5 ohms between the heated seat module and the heated seat switch and greater than 10,000 ohms between the heated seat module and ground?
Yes
GO to T17.
No
REPAIR the circuit. TEST the system for normal operation.
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T17 CHECK THE HEATED SEAT SWITCH
- Disconnect: Heated Seat Switch C3182.
- Measure the resistance between rear heated seat switch pins, component side, while pressing the indicated switch buttons and compare the results to the table.
- Is the heated seat switch OK?
Yes
INSTALL a new heated seat module. REFER to Heated Seat Module - Second Row Heated Seat Module - Second Row. TEST the system for normal operation.
No
INSTALL a new rear heated seat switch. REFER to Heated Seat Switch - Second Row Heated Seat Switch - Second Row.
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