Pinpoint Test B : The LH (Left-Hand) Heated Rear Seat Is Inoperative - Without Heated/Ventilated Seats
- Refer to Climate Controlled Seats
for schematic and connector information.
Normal Operation and Fault Conditions
REFER to: Second Row Seats - System Operation and Component Description .
Possible Sources
- Wiring, terminals or connectors
- RHVAC module
- Heater mat
- Heated seat module
- B1 CHECK THE HEATED SEAT SWITCH INPUT
- Ignition OFF.
- Disconnect Heated Rear Seat Module C3183A.
- While pressing and releasing the LH heated rear seat switch, measure:
Positive Lead Measurement / Action Negative Lead C3183A-2 Ground
Is the resistance less than 3 ohms when the switch is pressed and greater than 10, 000 ohms when released?
Yes GO to B3 No GO to B2 - B2 CHECK THE HEATED SEAT SWITCH CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect RHVAC Module C3198.
Are the resistances less than 3 ohms between the RHVAC module and heated seat module, and greater than 10, 000 ohms between the RHVAC module and ground?
Yes INSTALL a new RHVAC module. REFER to: Rear Heating, Ventilation and Air Conditioning (RHVAC) Control Module . No REPAIR the circuit. - B3 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- Disconnect Heated Rear Seat Module C3183B.
- Measure:
Positive Lead Measurement / Action Negative Lead C3183B-1 Ground
Is the voltage greater than 11 volts?
Yes GO to B4 No REPAIR the circuit. - B4 CHECK THE HEATER CIRCUITS AND HEATER MATS FOR AN OPEN
- Measure:
Positive Lead Measurement / Action Negative Lead C3183B-4 Ground
Is the resistance between 3 and 5 ohms?
Yes GO to B9 No GO to B5 - Measure:
- B5 CHECK THE HEATER MAT GROUND CIRCUIT FOR AN OPEN
- Disconnect LH Rear Backrest Heater Mat C3360.
- Measure:
Positive Lead Measurement / Action Negative Lead C3360-2 Ground
Is the resistance less than 3 ohms?
Yes GO to B6 No REPAIR the circuit. - B6 CHECK THE HEATER CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect LH Rear Cushion Heater Mat C3167.
- Measure:
Positive Lead Measurement / Action Negative Lead C3183B-4 Ground
Are the resistances less than 3 ohms between the heated seat module and the LH rear cushion heater mat, and greater than 10, 000 ohms between the heated seat module and ground?
Yes GO to B7 No REPAIR the circuit. - B7 CHECK THE CUSHION HEATER MAT FOR AN OPEN
- Measure the component side resistance
between:
Positive Lead Measurement / Action Negative Lead
C3167-1, Component Side
C3167-4, Component Side
Is the resistance between 0.7 and 1.5 ohms?
Yes GO to B8 No INSTALL a new cushion heater mat. REFER to: Seat Heater Mat Removal . - Measure the component side resistance
between:
- B8 CHECK FOR AN OPEN OR A SHORT TO GROUND BETWEEN THE HEATER MATS
- Measure:
Positive Lead Measurement / Action Negative Lead C3167-4 Ground
Are the resistances less than 3 ohms between the cushion heater mat and backrest heater mat, and greater than 10, 000 ohms between cushion heater mat and ground?
Yes INSTALL a new backrest heater mat. REFER to: Seat Heater Mat Removal . No REPAIR the circuit. - Measure:
- B9 CHECK THE TEMPERATURE SENSOR CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C3183A-3 Ground
Is any voltage present?
Yes REPAIR the circuit. No GO to B10 - B10 CHECK THE TEMPERATURE SENSOR CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Measure:
Positive Lead Measurement / Action Negative Lead C3183A-3 Ground
Is the resistance greater than 10, 000 ohms?
Yes GO to B11 No REPAIR the circuit. - B11 CHECK THE TEMPERATURE SENSOR AND CIRCUITS FOR AN OPEN
Is the resistance between 300 and 300K ohms?
Yes INSTALL a new heated rear seat module. REFER to: Heated Second Row Seat Module . No GO to B12 - B12 CHECK THE TEMPERATURE SENSOR FOR AN OPEN WITH THE HEATER MAT DISCONNECTED
- Disconnect LH Rear Cushion Heater Mat C3167.
Are the resistances less than 3 ohms?
Yes INSTALL a new cushion heater mat. REFER to: Seat Heater Mat Removal . No REPAIR the circuit in question.