How many light blubs are in there?

The temperature wheel does not light up, all the buttons do. I normally would not care but I am upgrading the radio so it is as good a chance as any to check it out and replace the bulb if necessary.

In the W126 unit, there are 2 blubs and it lights up all buttons and the temp wheel. So there must be something missing in the 300D.

Any helps appreciated.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.