With the possibility of LEDs everyhere, even in all the switches, the radio cannot be left out. The buttons have LED illumination orginally, as well as the red theft deterrent warning light but the display background is provided by tungsten bulbs. But even with the LEDs, they are of a yellowish-greenish tint and rather dim, as technology two decades ago allowed. Besides, if you have part of your illumination burnt out, you'll need to repair it, anyway. So, let's see how it can be done.
A project I've been contemplating for quite some time now, and with the constant advances in LED technology, I thought the time had finally come: LEDs all around the car. Not in the external traffic lights, for sure (with one exception, I'll return to that) but inside, with the large collection (nearly a hundred, really!) of bulbs everywhere. Let's count: instrument panel, warning lights, LH and RH display, switches, A/C panel, ceiling and rear lights, gloveboox, boot, door sill courtesy, radio surround, ashtray, cigar lighters, sunvisor. Quite a lot.
The XM Series 1 was born in the era of automotive bulbs. When it came to the Series 2, LEDs were already entering the scene. New switches like those on the dashboard started to come with LED illumination but earlier switches retained (and shared with other Citroëns of the time) remained with plain old bulbs in many switches of the door windows, electric seats or some center console switches. Retrofitting LEDs to these is a simple process with huge benefits: longevity (practically, eternity) of the LED, cool operation temperatures and lower power consumption are all welcome changes.