Hi, Mucka.<br /><br />You could, but it wouldn't be a good idea because the voltmeter would be a constsnt drain on the battery, even when everything else is turned off.<br /><br />First you need to find out why the voltmeter doesn't work. Is the meter bad? How was it wired before? Is the wiring bad?<br /><br />Normally, a voltmeter is wired to the 12v line that is turned on for accessories when the key is "ON".<br /><br />Good luck.
