1997 challenger MPEM problems

[bjs389]

before hitting the water yesterday i attempted to fire my boat on the trailer briefly to make sure everything was fine. I ran the blower for about 2 minutes and then turned it off. I attempted to fire the engines and nothing. The blower wouldn't even turn back on. My first thought was weak battery, so i grabbed my portable Die Hard power supply to jump the boat which I had previously done early on in the summer. Both engines fired right up. After putting the boat i the water i tried to re-fire and got nothing, so i again jumped it and she fired right up again. I cruised around slowly for a few but when I accelerated to about half throttle my gauges start bouncing around and going crazy. A few seconds later, both engines immediately shut down and there I sat. when I opened the engine compartment I noticed a loose wing nut on the negative battery terminal and some corrosion on both wires. I cleaned the wires, tightened the wing nut and attempted to start with no luck. I then checked the fuses inside the MPEM and found the blown 5A fuse. However when I replaced it and turned the battery back on, it blew again immediately. Then, after cleaning a little more corrosion off the terminals I put a 10 amp fuse in the slot to try again (dumb move I know but both of my 5 amp fuses were blown). The 10 amp fuse blew before I even turned the battery back on!! All other electrical components seem to be fine (blower, lights, etc...) but I get no beeps and neither engine attempts to fire. I have read several posts on here about this same issue and ways to fix it without spending $600+, so i pulled the MPEM out of the boat and brought it home. It sounds like i blew a diode inside the module and you can replace them for about $15-$20. I am hesitant to begin tearing the thing apart to locate the diode it there is a possibility of this not being the problem. ANY advice is greatly appreciated. I am a new member and I have learned so much from this site already!!

 

[seadooya]

dig away, man. look up "borderpatrol" thread, about replacing the diode/what it looks like.