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Home >> Infiniti >> 2009 >> M45 Base >> Repair and Diagnosis >> Body & Frame >> Windows >> Glass, Window System & Mirrors >> Service Information >> Rear Window Defogger >> System Description
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System Description

The rear window defogger system is controlled by BCM and IPDM E/R.

The rear window defogger operates only for approximately 15 minutes.

Power is at all times supplied

With the ignition switch turned to ON or START position,

Power is supplied

With the ignition switch turned to ACC or ON position,

Ground is supplied

When rear window defogger switch in multi-function switch is turned to ON.

Then multi-function switch recognizes that rear window defogger switch is turned to ON.

Then it sends rear window defogger switch signals to AV control unit via AV line.

When AV control unit receives rear window defogger switch signals, and display on the screen.

Then AV control unit recognizes that rear window defogger switch is turned to ON.

Then it sends rear window defogger switch signal to BCM via DATA LINE (CAN H, CAN L).

Then BCM recognizes that rear window defogger switch signal.

Then it sends rear window defogger request signal to IPDM E/R via DATA LINE (CAN H, CAN L).

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

Ground is supplied

And then rear window defogger relay is energized.

When rear window defogger relay is turned ON, signals are transmitted.

Rear window defogger terminal 2 is grounded through grounds B702.

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

Door mirror (LH and RH) terminal 8 is grounded through body grounds M16 and M70.

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