Test O: The Heated Seat Is Inoperative - Driver

PINPOINT TEST O: THE HEATED SEAT IS INOPERATIVE - DRIVER

O1-O2:

O2-O4:

O4-O5:

O5-O6:

O6-O7:

O7-O8:

O9:

O10-O12:

O12-O13:

O13 Continued:

O14-O15:

O15-O17:

O17-O18:

Normal Operation
The heated seat module receives ignition voltage feed on circuit CBP19 (BN/WH), battery voltage feed on circuit SBB11 (BU/RD) and is supplied ground on circuit GD139 (BK/YE). When ignition switched power is supplied and the driver heated seat button on the electronic automatic temperature control (EATC) module is pressed, a momentary ground signal is sent to the heated seat module on circuit CHS29 (WH/BU) to command the system ON or OFF. Upon receiving a signal, the heated seat module will decrease one setting (the sequence is HI, LO, OFF, HI, etc.). The heated seat module supplies voltage to the cushion and backrest heater mats on circuit CHS02 (YE/BU). Ground to the heater mats is provided on circuit GD126 (BK/WH). 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 RHS05 (YE/VT) and monitors the signal from the temperature sensor on circuit VHS26 (VT) for controlling current flow to the heater mats. The heated seat module is designed to remain ON, heating the seat and maintaining temperature until switched OFF or a 15-minute time-out period occurs.

Possible Causes
An inoperative driver heated seat can be caused by:
- an open fuse.
- faulty wiring, terminals or connectors.
- a faulty heater mat.
- a faulty heated seat module.
- a faulty EATC module.