For 1990-2009 cars

## Interior Lights Dimming Circuit Description Oldsmobile

### Oldsmobile

When the park lights are on, battery positive voltage (B+) is applied via CKT 32 (YEL) to the interior lamp control module. The interior dimming switch in the headlamp switch is a variable resistor which applies the dimming input via CKT 44 (DK GRN) to the interior lamp control module. The interior lamp control module supplies a variable voltage via CKT 8 (GRY) to the incandescent lights in response to the interior dimming input received. The interior lamp control module receives ground from G105 via CKT 251 (BLK/WHT).

The radio, heater and A/C control assembly, and instrument cluster each have a vacuum fluorescent (VF) display. When each module receives an input that the ignition switch is turned to the RUN position, each module activates the VF display at the full intensity. When the park lights are on, the radio and instrument cluster receives the dimming level from an input on CKT 8 (GRY). The radio then relays this information to the heater and A/C programmer. All modules with VF displays then adjust the dimming level of their VF display in order to match the level of the incandescent lamps.

## Interior Lights Dimming Circuit Description Buick

When the park lights are on, battery positive voltage (B+) is applied via CKT 32 (YEL) to the interior dimming switch in the headlamp switch. The interior dimming switch controls the amount of current applied to the incandescent lights. As the amount of current increases, the lamps become brighter. As the amount of current decreases, the lamps become dimmer.

The following components each have a vacuum fluorescent (VF) display:

• | Radio, heater and A/C control assembly

• | Instrument cluster

• | Head-up display

When each module receives an input that the ignition switch is turned to the RUN position, each module activates the VF display at the full intensity. When the park lights are on, each module receives the dimming level from an input on CKT 8 (GRY). All modules with VF displays then adjust the dimming level of their VF display in order to match the level of the incandescent lamps.

## Interior Lights Dimming Circuit Description Pontiac

When the park lights are on, battery positive voltage (B+) is applied via CKT 32 (YEL) to the remote dimmer module. The interior dimming switch in the lamp dimmer switch is a variable resistor which applies the dimming input via CKT 44 (DK GRN) to the remote dimmer module. The potentiometer in the lamp dimmer switch cannot provide enough current in order to operate the incandescent lights. The remote dimmer module amplifies the current, applying a variable voltage to the incandescent lights. As the amount of current increases, the lamps become brighter. As the amount of current decreases, the lamps become dimmer.

The radio, heater and A/C control assembly, instrument cluster, and passenger climate control each has a vacuum fluorescent (VF) display. When each module receives an input that the ignition switch is turned to the RUN position, each module activates the VF display at the full intensity. When the park lights are on, the radio receives the dimming level from an input on CKT 8 (GRY). The radio then relays this information to any other modules with VF displays. All modules with VF displays then adjust the dimming level of their VF display in order to match the level of the incandescent lamps.