Back of the clock should have one wire that is constant 12 volts (red-white - for the time keeping) and one that is switched 12 volts (red-green - for the display). Test the switched line to see if it is staying on. If so, trace that wire back to where it comes from. Normally powered off the cigarette lighter circuit/fuse, so perhaps that circuit has been modified to stay hot all the time or the relay that controls it is stuck on.

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Project: 4Crawler
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