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Circuit Operation - Interior Lights Dimming

Battery voltage is applied at all times to the Headlight Switch. When the Headlight Switch is in "PARK" or "HEAD," voltage is applied to the Pulse Width Modulated (PWM) Module. The output from the Module is a PWM signal used to light the Instrument Panel lights. The pulse width is modulated by the Dimmer Switch. The longer the pulse width, the brighter the lights become.