To be totally honest I purchased the manual and it's like reading French to me. I've tested the battery when it's idle which is 12.7, then when the engine is up to full rev it drops to 12.6. Then I tested the three yellow wires that lead into the mpem, and I cha get the fuses in the mpem and in the back electric box, but I still get the 12v low message on dash. Plus when you start her up and leave idle engine will tick over for maybe 30 secs then stop.