System Description

The rear window defogger system is controlled by BCM (Body Control Module) and IPDM E/R (Intelligent Power Distribution Module Engine Room).

The rear window defogger operates only for approximately 15 minutes.

Power is at all times supplied

through 20A fuse [No. 75, and 80, located in the IPDM E/R]
to rear window defogger relay terminals 3 and 6.
through 10A fuse [No.12, located in the fuse block]
to rear window defogger relay terminal 1.
through 15A fuse [No. 32, located in the fuse block (J/B)]
to A/C and AV switch terminal 1.
through 50A fusible link [letter M , located in the fuse block (J/B)]
to BCM terminal 55.
through 15A fuse [No.22, located in the fuse block (J/B)]
to BCM terminal 42.

With the ignition switch turned to ON or START position,

Power is supplied

through 15A fuse [No.1, located in the fuse block (J/B)]
to BCM terminal 38.

Ground is supplied

to BCM terminal 49 and 52
through body grounds M35, M45 and M85.
to A/C and AV switch terminal 5
through body grounds M35, M45 and M85.
to IPDM E/R terminals 38 and 60
through body grounds E21, E50 and E51.

When rear window defogger switch in A/C and AV switch is turned to ON, Ground is supplied

to BCM terminal 9
through A/C and AV switch terminal 16
through A/C and AV switch terminal 5
through body grounds M35, M45 and M85.

Then rear window defogger switch is illuminated.

Then BCM recognizes that rear window defogger switch is turned to ON.

Then it sends rear window defogger switch signals to IPDM E/R and display control unit (with navigation) or display unit (without navigation) via DATA LINE (CAN H, CAN L).

When display control unit (with navigation) or display unit (without navigation) receives rear window defogger switch signals, and display on the screen.

When IPDM E/R receives rear window defogger switch signals,

Ground is supplied

to rear window defogger relay terminal 2
through IPDM E/R terminal 52
through IPDM E/R terminal 38 and 60
through body grounds E21, E50 and E51,

and then rear window defogger relay is energized.

When rear window defogger relay is turned ON,

Signals are transmitted,

through rear window defogger relay terminals 5 and 7
to rear window defogger terminal 1
Rear window defogger terminal 2 is grounded through body grounds B15 and B45.

With power and ground supplied, rear window defogger filaments heat and defog the rear window.

When rear window defogger relay is turned to ON,

Power is supplied

through rear window defogger relay terminal 7
through fuse block (J/B) terminal 2C
through 15A fuse [No. 8, located in the fuse block (J/B)]
through fuse block (J/B) terminal 5B
to door mirror defogger (driver side and passenger side) terminal 1.

Door mirror defogger (driver side and passenger side) terminal 2 is grounded through body grounds M35, M45 and M85.

With power and ground supplied, rear window defogger filaments heat and defog the rear window and door mirror defogger filaments heat and defog the mirror.