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Heated Glass Element: Description and Operation

System Description
The rear window defogger system is controlled by the smart entrance control unit. The rear window defogger operates only for approximately 15 minutes.

Power is supplied at all times
- to rear window defogger relay terminal 3
- through 20 A fuse (No.56, located in the fuse and fusible link box) and
- to rear window defogger relay terminal 6
- through 20 Afuse (No.57, located in the fuse and fusible link box)
- to smart entrance control unit terminal 10
- through 7.5 A [No.24, located in fuse block (J/B)]

With the ignition switch in the ON or START position, power is supplied
- through 7.5 A fuse [No.11, located in the fuse block (J/B)]
- to the rear window defogger relay terminal 1, and
- to smart entrance control unit terminal 33.

Ground is supplied
- to terminal 1 of the rear window defogger switch
- through body grounds M4, M66 and M147(with navigation system),
- to terminal 32 of the A/C auto amp.
- through body grounds M4, M66 and M147 (without navigation system), or
- to smart entrance control unit terminal 16
- through body grounds M77 and M111.

When the rear window defogger switch is turned ON, ground is supplied
- through terminal 2 of the rear window defogger switch (with navigation system), or
- through terminal 31 of A/C auto amp. (without navigation system)
- to smart entrance control unit terminal 39.

Terminal 2 of the smart entrance control unit then supplies ground to the rear window defogger relay terminal 2.

With power and ground supplied, the rear window defogger relay is energized.

Power is supplied
- through terminals 5 and 7 of the rear window defogger relay
- to the rear window defogger.

The rear window defogger has an independent ground.

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

When the system is activated, the rear window defogger indicator illuminates in the rear window defogger switch.

Power is supplied
- to terminal 3 of the rear window defogger switch (with navigation system), or
- to terminal 30 of the A/C auto amp. (without navigation system)
- from terminal 7 of the rear window defogger relay.

Terminal 4 of the rear window defogger switch (with navigation system) or terminal 32 of the A/C auto amp.
(without navigation system), is grounded through body grounds M4, M66 and M147.