skidude

iTrader: (3)

I tried to flash the firmware using the stim, but when I plugged the stim into MS, the case shocked me. I took the case off, and it's the heatsink that is doing the shocking.

Any suggestions on what I should check?

Oh, the firmware wouldn't flash, and now MS doesn't want to talk to Megatune.

skidude

iTrader: (3)

It is flashing the firmware, but I still don't like how it zapped me.

Saml01

iTrader: (9)

Static maybe?

skidude

iTrader: (3)

No, I'm sure it wasn't static. It was constant for as long as I held my hand on it. Then it just stopped.

Once I re-flashed the firmware, it connected to megatune alright. I have to investigate the error where it said the signature didn't match though.

skidude

iTrader: (3)

Megasquirt still zaps me but not all the time. I can't figure out what makes it do it, but sometimes it will shock me and other times it won't.

Edit: It zaps when it is plugged into the computer. It doesn't need to be powered with the stim or anything, just when the computer is plugged in.

Any ideas yet? I don't even know where to start looking.

Braineack

iTrader: (62)

dont think you'd check the serial connector first?

skidude

iTrader: (3)

The voltage is obviously coming from the serial connector though. Once it enters megasquirt it is finding its way to the heatsink, then to the case.

There is 9.5 volts at the end of the serial cable. Apparently this is enough to for me to feel on my forearm, which is where I keep noticing it. (I brush across the MS case when I type on the keyboard)

Braineack

iTrader: (62)

i had an issue once with the little tabs the bungs screw into. once it swiveled around and made contact with a component and grounded the circuit. I believe it caused me to only run on two cylinders...

go through your wiring and see where you failed.

skidude

iTrader: (3)

I removed all the things attached to the heat sink, and the heat sink fell off, and the metal strip under it is still electrified. Any tips on what I should look for while I search for my failure?

Matt Cramer

The metal strip under the heat sink is the high current ground plane. How's your power supply to the Stim grounded?

skidude

iTrader: (3)

It's a 9v battery, so it's not grounded at all.

After I flashed the firmware, it stopped shocking me. I haven't had it plugged into the stim much since then, but it hasn't threatened to do anything out of the ordinary since. It's now in the car working very nicely.