Corrupting Firmware...possible problem

[cygnusx1]

First, the question: Suppose a blowing fuse in the brake light circuit is cause by a chewed wire that is grounding out intermittently. Can the blowing fuse for the brakes/hazard cause the firmware to corrupt or overheat the VB921? (voltage correction for dwell)

 

My thoughts are that if the voltage drops out low due to a short in another circuit, this might make MSII increase the dwell to compensate. If it spiked the dwell setting to comp for the voltage drop, it could overheat the VB921 and cause the spark to go haywire until it cooled off.

 

 

 

My Situation:

Ok since DIY re-did my firmware for me, I have not had anymore problems...except for the hole in the headgasket. That's another story. Anyway, when we had the QuadState Z meet here in NY, my Z blew the fuse that feeds the brake lights and the hazard circuit. I scoped the fuse block for a ground and it came up clean. I dropped in another 20A glass fuse and the car drove fine for the next 100 miles or so. Yesterday, I went to take a spin in the Z before I pull the head off, and I got stuck. It was running fine and I felt a sudden split second power drop and then I saw tons of black/gray smoke out the back and the engine quit. I managed to roll almost all the way home and came to a stop on an uphill section about 200 yards from my driveway.

 

I went to put on the hazards and they didn't work. I guessed that the fuse blew again...I was right. I tried cranking the motor and the fuel pump was on which means the MSII was also on. During cranking, the Tach needle was jumping all over the place but I was not getting ignition. We pushed the car up the hill for a few minutes. After about 10 minutes, it fired up and I drove it home.

 

I reloaded the map just for peace of mind. The car runs fine in the garage and I put in another 20A fuse for the hazard/brakes. The fuse is holding up fine, for now. However, the MSII will not power up if connected to the laptop with megatune software closed. If I run megatune, the car starts. If I connect to Megaview, the car starts. If I connect to nothing, the car starts. If it's connected to the laptop with only Windows XP, the car won't start. I suspect the firmware needs reloading again due to the wierd boot pattern.

 

I designed a DEDICATED 10g feed from the battery to the MSII and the fuel/ign system, and a DEDICATED 10g ground to the battery from the MSII and the fuel/ign system. The power circuits are solid.

 

Confession: I do not have a power conditioner for MSII yet. (on order)