CPU EXPLOSION!!!!!

[turbothis]

4th megasquirt build. All was fantastic. Connected battery directly to pins 26 and 19 and got no LED's and "expected" error during Extra flash. Double checked baud, battery voltage and swapped ground to pin 10 and reconnected power. LED's lit briefly and CPU literally exploded instantly. I took shrapnel in the forearm. This is megasquirt number 4 with literally no issues so I'm at a loss. Going through test of components now but hoping it was a defective CPU?

[racingmini_mtl]

Pin 26 is the 5V Vref pin. You applied 12V to the CPU which is why it failed in such a way. You may well have fried other chips too. Pin 28 is the 12V supply pin.

Jean

[turbothis]

Pin 26 is the 5V Vref pin. You applied 12V to the CPU which is why it failed in such a way. You may well have fried other chips too. Pin 28 is the 12V supply pin.

Jean

Thanks, figured that out after some testing. d*** font on the wiring diagram is so small and cutoff I swore it read 26. Was wishing I could delete my original post. Quick end to what would have been a fun night.

[DaveEFI]

You need quite a bit of current to blow something like that. Get yourself a low current mains supply that limits the maximum current. That will protect better than a fuse. We all make mistakes, so best to limit the damage one can do.

[Six_Shooter]

The good news is that MS1 CPUs are pretty cheap.

This is why I look at several diagrams to verify the pins or better yet MSExtra manuals, that nbot only have diagrams but list the number and function of each pin (though I'm not sure there's a V2.2 board manual for MSExtra...), and will grab my DMM to verify if I'm still unsure of what a pinout is telling me.