Two things, there is some fuses that will control this. They are in one of 3 places. One is under the hood, one is under the rear seat, one is to the left of the dash with the driver's door open.
Two, the bulbs can be blown that backlight it. You have to take out the cluster for this.
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Benzmac:
Donnie Drummonds
1992 500E (very soon I hope

1981 280GE SWB
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