I blew my VB921s...

[bjl4776]

Im running MS-I v3.0 on a 95 BMW 2.5L DOHC w/ COP. I am using 6 VB921s to power the coils. Well i didnt have the setting right and got jumpy and turned the key on with the spark not being inverted. Well a couple seconds after i turned the key on they all blew. Well im also running a relay board and all of the grounds are through the relay board. Well i disconnected the ignition circuit and turned it on to see if the rest of the board still worked. When i turn the key on the MS would turn on for a second and right back off. I checked the realy board and the entire ground side was fried. So i took MS out and hooked it up to the stimulater and it didnt work at all. At what battery voltage does the stim stop working at, and is it possible that the board is blown. I dont think it could be because it did turn on with 12v for a sec. and it must of just turned right back off because of high resistance of the ground side because it was all blown.

[jsmcortina]

If there is a short circuit on the board one of the polyfuses may be opening.

What fuses were you running on your ignition side and did you connect the coils via the fuel pump relay?

James

[bjl4776]

My coils are powered through the Main Relay and Fuses that came stock on the car. I mounted the VB921s to a second heatsink on the bottom of the board, is it possible i could of overheated something else in the process. Or where should start to test for a short on the board. And could the initial meltdown of the relay blow the polyfuses from heat or what night.

[jsmcortina]

Always connect the coils via the fuel pump relay and double check the fusing. These are protection in case of code error/crash or config error.

It is very difficult to remotely diagnose the board. Remove the CPU and start going through the assembly guide to check out the power supply components.

James

[Jon k]

Brandyn did you confirm power supply test is proper?