Does the voltmeter shut off with the key? YES...If not, the answer is yes, voltmeter will drain the battery
WHAT ARE WE WORKING ON? 1962 VALIANT 200, 170 /6
What wiring changes from stock have you made? ADDED VOLT METER BY USING IGNITION SW POSITION 2 AND GROUND. BYPASSED AMMETER (SPLICED WIRES A-1 AND R6A)
What have you done to check this?
What you need to do is, shut EVERYTHING off, and check trunk/ underhood lamp if present, glove box lamp, everything. Remove battery ground cable. Connect a 12V test lamp in series with the battery. A real lamp bulb, not an LED. Does it light? If not take your multimeter and set it up for maximum current and put that in series from the battery NEG to the ground cable. Be careful, as a multimeter in current mode is a DEAD SHORT when doing this so be methodic and careful about connections. If you do not read anything on the high current (10A or 20A) scale, switch down to lower ranges.
Make sure voltmeter is off or disconnected. Now pull fuses one at a time to see if problem goes away. If not, disconnect alternator output wire--the big one on the stud. Be careful not to short the wire to ground.
