View Full Version : MSD 7ML2 problem

08-01-2003, 01:44 PM
We have a 7ML2 box mounted on our car and the last few times to the track we have had a problem with the battery going dead after a couple of runs. We traced it down to the MSD unit. If we disconnect the main power lead to the box the draw goes away. We have not had a running problem or a problem with it not shutting off with the ignition switch, yet it seems the box is staying energized. Got any ideas? For now I am going to wire a relay into the main power circuit so that it will have power cut off to it when the ignition is off....this way I can go play tomorrow!

08-03-2003, 07:26 PM
The MSD heavy Red wire should not draw any current until the small gauge Red wire sees 12 volts. The small gauge Red wire should be attached to a switched 12 volt source like your ignition key on/off switch or to a toggle on/off switch. Check the small gauge Red wire with a volt meter to make sure you have no voltage at that point with the ignition key/toggle switch in the off position.

MSD Tech1