Bi polar misshap.. + on - and vice versa.. And then smoke

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jompa_a
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Joined: Sat Jul 14, 2012 4:46 am

Bi polar misshap.. + on - and vice versa.. And then smoke

Post by jompa_a »

Hello.

So, I have MS2Extra and installed the boostcontrol. Like this: http://www.msextra.com/doc/ms2extra/MS2 ... .htm#boost
Its been laying for 6 month or so and I wanted to update the firmware. For some goddamn reason I mixed up the 12v feed with ground to the ms. :oops:
They were connected for 4 or 5 seconds before I realised what I had done. So I switched them around and connected.
The MS connected to the laptop and then the smoke came.

I opened the MSbox and found the the diode to the boostcontrol went.. The wire to the drainpin and the ground wire from the IRLZ44 FET were also burnt.

Just to clearify how I wired the boostcontrol in the ms. I used SPR1 to the Drain, JS2 to the Gate and used the groundarea on the protoarea to ground it.
Then I wired the diode between pin 28 (on the DB37) and the Drain.

So.. My question is: How much did I destroy and did the diode die because of the mixup between + and - or did I wire it in wrong?
I also have a vague memory of that I used a IN4001 diode.


And you dont need to say it. Yes, it was dumb to mixup the + and - :(
Greetings from Sweden /Jonas
billr
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Location: Walnut Creek, Calif. USA

Re: Bi polar misshap.. + on - and vice versa.. And then smok

Post by billr »

Dumb? Yes, of course, but I have done it myself on many things, including my MS3/3X! Is this a V3.0 mainboard? I was quite pleased to find that is well-protected from this reverse polarity scenario and no harm was done to mine. The mod for boost control is one I am unfamiliar with. If someone else doesn't join in here about that I will look at that mod and learn enough to discuss it with you. Let's give it a day or two more for others to join, my learning about the mod would be pretty much wasted effort as I have no need to ever use boost.

Edit: I see you are in Sweden. Can you offer some comments in this thread: http://www.msextra.com/forums/viewtopic ... 94&t=54551
jompa_a
Helpful MS/Extra'er
Posts: 77
Joined: Sat Jul 14, 2012 4:46 am

Re: Bi polar misshap.. + on - and vice versa.. And then smok

Post by jompa_a »

HI.

Thank you for helping me resolve this stupid misstake.

And yes, it is a v3 board.

Edit: I tried to flash the ms anyway with new software and that worked. it still connects just fine to the laptop.
Greetings from Sweden /Jonas
jompa_a
Helpful MS/Extra'er
Posts: 77
Joined: Sat Jul 14, 2012 4:46 am

Re: Bi polar misshap.. + on - and vice versa.. And then smok

Post by jompa_a »

Is really none exept billr willing to help me :(
Greetings from Sweden /Jonas
billr
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Joined: Sun May 15, 2011 11:41 am
Location: Walnut Creek, Calif. USA

Re: Bi polar misshap.. + on - and vice versa.. And then smok

Post by billr »

Let's hope that "bump" of the thread nets you some new participants. If it doesn't, after another day or so, I'll do some research on that mod and see if I can help.
kjones6039
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Re: Bi polar misshap.. + on - and vice versa.. And then smok

Post by kjones6039 »

jompa_a wrote:Is really none exept billr willing to help me :(
I doubt it is a matter of being "willing"! More likely it's a matter of the person with the expertize on your particular setup, finding the time to donate to your individual issue.

Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/extra 3.4.2 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
TinyIOX from JBPerformance
DaveEFI
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Location: SW London, UK

Re: Bi polar misshap.. + on - and vice versa.. And then smok

Post by DaveEFI »

jompa_a wrote:Is really none exept billr willing to help me :(
It's a pretty simple circuit. Replace the Mosfet and the diode and check any tracks on the PCB connected to it.
Rover SD1 3.5 EFI
MS2 V3
EDIS
Tech Edge O2
London UK.
Matt Cramer
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Re: Bi polar misshap.. + on - and vice versa.. And then smok

Post by Matt Cramer »

Also, it sounded as if you had the situation under control at this point; the ECU was powering up, and you should be able to test what does and does not work on a Stim. I'd replace the boost control circuit, but beyond that, I'd simply confirm the circuits were operational.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
jompa_a
Helpful MS/Extra'er
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Joined: Sat Jul 14, 2012 4:46 am

Re: Bi polar misshap.. + on - and vice versa.. And then smok

Post by jompa_a »

Thanks everyone.

I havent gotten around to test it yet. I just wanted to say thank you for the help.
Greetings from Sweden /Jonas
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