Voltage for the interior backlighting components is supplied from the body control module (BCM). The BCM applies a voltage reference through
the 12 V reference circuit to the headlamp and panel dimmer switch. When the dimming switch is placed in the desired position, the dimmed voltage
setting is applied from the headlamp and panel dimmer switch through the instrument panel (I/P) lamp dimmer switch signal circuit to the BCM. The
BCM then applies the dimmed voltage to the lamp supply voltage circuits and they are dimmed to the correct level.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The BCM detects a voltage that is lower than 0.10 V on the I/P lamp dimmer switch signal circuit.
The BCM detects a voltage that is higher than 4.97 V on the I/P lamp dimmer switch signal circuit.
Action Taken When the DTC Sets
The I/P lamps are not illuminated.
Conditions for Clearing the DTC