MS2 v3.0 B&G board no spark B from R29/D16, m20 wasted spark

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Ridingretro
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MS2 v3.0 B&G board no spark B from R29/D16, m20 wasted spark

Post by Ridingretro »

Hi there before we start I'm not the best at electronics so building this was a huge learning curve :)
I'm having a spark issue with my ms2 v3.0 build.

I have the coil pack set up on the bench (bosch 0221503010) and have my IGBT's wired like this:
Image with 330ohm resistors inline with the Ignitors.

I can get A and C to spark using the output test in Tunerstudio.. but nothing with B, No L.E.D (D16) pulse like the other two.

Also swapped the outputs around and the coilpack works fine, Put a new ignitor and resistor on for spark B still nothing.

I've tested the L.E.D and that works, R28 reads 330ohms R29 reads 1k, Tested the transistors (2n3904-c24) using This videofor a guide

The readings if this helps.. Q6 Emitter = 1025 collector = 986 Q7 Emitter = 1026 collector = 964 Q8 Emitter = 1040 Collector = 964

I'm stuck at the minute as I don't know what else to test.. I'll post a msq but any advice would be great.

ohh the boards also wired as many guides have suggested.. TACHSELECT-VRIN TSEL-VROUT
DaveEFI
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Re: MS2 v3.0 B&G board no spark B from R29/D16, m20 wasted s

Post by DaveEFI »

You can check the LEDs and driver circuits quite easily. Carefully remove the daughter board, and apply 5v (from the proto area) to pins 7,8 & 9 on the socket in turn. Each LED should light in turn. If they do, chances are it's a software thing.
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grom_e30
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Re: MS2 v3.0 B&G board no spark B from R29/D16, m20 wasted s

Post by grom_e30 »

have you checked the metal case of your spark b igbt is insulated from ground?
1990 bmw 320i daily driver with m20b25 ms3 sequential fuel, 380cc injectors, d585 coil near plug, home made cam sync, launch control, fan control, vss, homebrew egt logging what's next????
billr
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Re: MS2 v3.0 B&G board no spark B from R29/D16, m20 wasted s

Post by billr »

Is there some confusion here? None of those spark outputs are "IGBTs", they are logic-level (sort of 0-5V). There is one coil driver (IGBT?) on the mainboard, Q16, but where are your other two (or three)? Is that Bosch module have coil drivers, or do you have external drivers between the MS and a pack of "dumb" Bosch coils? If the Bosch does have drivers, what it the input resistance?
Ridingretro
MS/Extra Newbie
Posts: 2
Joined: Sat May 06, 2017 4:06 pm
Location: Wales

Re: MS2 v3.0 B&G board no spark B from R29/D16, m20 wasted s

Post by Ridingretro »

Well thank you all for the quick responses. I didn't expect my "newbie" post to get approved so quick.
grom_e30 wrote:have you checked the metal case of your spark b igbt is insulated from ground?

yeah I did check that originally it seems good, I de-soldered the old wire/resistor/igbt combo and had a completely separate igbt wired up rule out any potential problems when I made my second test and nothing.

DaveEFI wrote:You can check the LEDs and driver circuits quite easily. Carefully remove the daughter board, and apply 5v (from the proto area) to pins 7,8 & 9 on the socket in turn. Each LED should light in turn. If they do, chances are it's a software thing.

I've literally just tried what you said and it appears to be something with the board as pin 7 illuminates D14, pin 9 illuminates D15 but pin 8 isn't doing anything for D16 :? d***.. I was hoping it was going to be a software issue.
Is there any other components inline from the Pin 8 trace back to D16. I wonder if I've blown something or a poor solder joint or fried trace.

I'll try and pull it out of the case tonight for a better look.

billr wrote:Is there some confusion here? None of those spark outputs are "IGBTs", they are logic-level (sort of 0-5V). There is one coil driver (IGBT?) on the mainboard, Q16, but where are your other two (or three)? Is that Bosch module have coil drivers, or do you have external drivers between the MS and a pack of "dumb" Bosch coils? If the Bosch does have drivers, what it the input resistance?
Yea they're dumb type..I didn't use the Q16 slot.. The 3 external Drivers are mounted on another heat sink spaced above the main heat sink.. mainly for ease of access when the case is off as the manual says to reduce spark dwell when they become "hot to the touch" :)


Thanks again for all your quick responses.. hopefully its something that can get fixed easily.



(EDIT)
After removing it from the case the problem lies with the trace from pin 8, so I've run a wire to jump the trace and its working :D
But I'm getting a tiny bit of spark interference from the 2 B plugs when the 2 other C plus are sparking, not sure if that's to do with plugs being so close when igniting.
I'll need to confirm when its all back in the car with proper multiplug connectors.

Thanks for pointing me in the right direction.
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