The generic electronic module (GEM) allows operation of the rear window wiper functions when the ignition switch is in the RUN or AC position only. The GEM controls the cycling of the rear window wiper motor through the rear window wiper relay.
There are four modes of operation: off mode, interval mode, on mode, and wash mode.
In the off mode, there is no rear wiper motor activity and rear wiper motor is in the PARK position.
When the wiper/washer switch is placed in the interval position, the GEM activates the wipe cycle of the rear window wiper motor. Once the wiper cycle has reached the LOW position, after the initial wipe, the GEM will start a cyclical timing function.
The GEM cycles the rear window wiper motor continuously at a set-speed setting. The GEM provides ground to activate the rear window wiper relay.
When the wiper/washer switch is pressed and held for 0.1s or more, the GEM supplies ground through the wiper/washer switch and cycles the rear window wiper motor three times.