How to prevent power drain when car is off

Posted by Henk909303 on Feb 11, 2022; 1:17pm
URL: http://bluesaab-forum.90.s1.nabble.com/How-to-prevent-power-drain-when-car-is-off-tp1827.html

When my car is turned completely off I measure a current draw of 70mA caused by the Bluesaab module. Since I do not use my car as much as I used to my battery now goes flat now and then. So I am looking to get rid of this current leakage.

I know some ideas have been floating around as to limiting the power draw from a software point of view, but I am currently looking at a hardware solution.

From the schematics I noticed there is only one power input (12V) currently available at the CD-changer connection, which is always on.

My simple idea for a solution is to not feed this pin from the CD-changer loom, but from any other wire in the area that provides a 12v that switches with the ignition switch. I think the wiring for the tow bar should have one (My car doesn't have a tow bar but I assume the wiring is there). Another option would be one of the wires for the taillights.

The main issue I think there might be is that I can image that as the 12V in the CD-changer loom is intended for audio equipment, it might have filtering applied, which other 12V wires might not. Does anyone know if this would indeed be an issue?

And the other question is; should the Bluesaab module have no issues with being switched off completely?

Are there any other simple solutions I am overlooking? Should I maybe not perform the switch of wiring in the boot, but in the driver's foot well instead? I imagine this might be simpler as this area is easier to access.