Motronic Pin 27 and Megasquirt

[JakeusSnakeus]

Is there any good reason why you couldn't use Motronic Pin 27 (start input) as the +12v source to power Megasquirt?

Besides the fact the cable looks a little skinny, its probably the most simple method of making the thing turn on and off with the key.

[Speedtouch]

You may be able to use it to directly power the MS, but best to ensure the supply has a fuse of suitable rating, or better still, use it instead to power a relay-switched feed to the MS ECU.

[HairyScreech]

Last MS I did I ended up putting a direct feed onto a switch, was very handy when tuning/fault hunting and burning firm ware. However that was not a normal road car so a switch on the MS feed was handy as a kill switch/fuel shut off switch.

On the E30 you can take a feed off the ignition switch directly with no problems.
Pin 27 is actually just a feed from the ignition switch so it would not actually be hard to trace it back and upgrade the wire to a larger gauge, adding a fuse or a cut off switch at the same time.

[chu346]

This is how I wired mine

http://farm4.static.flickr.com/3096/259 ... 6bfc_o.png