Test Z: The Heated Seat Is Inoperative/Does Not Operate Correctly - Left Rear

PINPOINT TEST Z: THE HEATED SEAT IS INOPERATIVE/DOES NOT OPERATE CORRECTLY - LEFT REAR

Z1:

Z1-Z2:

Z3-Z5:

Z5-Z7:

Z7-Z8:

Z9-Z10:

Z11-Z13:

Z13-Z14:

Z15-Z17:

Normal operation
The heated seat module receives battery voltage on circuit CBP35 (YE/GY) and ignition voltage on circuit SBB07 (WH/RD), 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 commanded ON, voltage is supplied to the heated seat switch from the heated seat module on either circuit CHS48 (YE) (hi heat mode) or circuit CHS49 (VT) (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) and ground to the heater mats 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 monitors the temperature sensor on circuit VHS42 (GN) 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 power is switched OFF.

Possible Causes
An inoperative left rear heated seat can be caused by:
- faulty wiring, terminals or connectors.
- a faulty heater mat.
- a faulty heated seat module.
- a faulty heated seat switch.