The instrument panel and pedestal backlight is controlled by the Integral Light knob found on the left side of the aircraft pedestal.
To enable your panels to light up on your flight simulator, a backlight 5 volt distribution board is required. This enables you to control multiple panels with one potentiometer. There are several backlight dimming boards available on the market — FlightDeck Solutions (FDS) dimming solution was previously discussed here.

An original Integral Light potentiometer used in the diming panel, rated at 470 ohms
Unfortunately the genuine dimming pot is rated as 470 ohms. The FDS boards accepts a 50 k ohms pot. By attaching the genuine pot with these boards the backlight could not be turned off completely, or maximum backlight brightness could not be reached.

Genuine A320 Integral Light pot on the left, replacement pot on the right
An alternative pot with the same size specifications but rated at 50 k was searched for tediously on eBay and the Internet. Eventually one pot was settled on – 9mm Alpha B50K 50K Linear Taper Potentiometer D Shaft RT-Angle PC Mount. When the replacement pots did arrive, surprisingly they did not match up in size to the genuine pot and were relatively smaller despite careful measurements.
However, with careful placement at the center of the panel, and tightening the nut and the knob over the Alpha pot, the Sim was once again in business.
The overhead also has an Integral light controlled by one pot and most likely will also have to be replaced.
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