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Megasquirt Short to Ground Q15 Transistor

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Old Dec 12, 2006 | 12:21 AM
  #1  
SCCA RX7 RACER's Avatar
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Gen 2 Raced Hard NA 13B
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From: Canada
Smile Short to Ground Q15 Transistor

Hi All,

At the race track this year I ran in to a problem with the secondary injectors not kicking in. I had a spare back up V3 board and M1 chip to swap out to get me going.

I performed several test comparing the primary injector circuit to the secondary injector circuit. I found that my Q15 transistor was allowing the signal from the U4 chip out put "B" to go to ground rather than to the Q5 transistor to fire the secondary injector.

I ran this board at the track for about 8 weekends and put a total of 30 hours on it. My second back up board finish the season with no problem.

My question is. Is it possible that I have done some thing wrong that would cause the transistor to fail or is it a faulty transistor letting me down?

Best Regards
SCCA RACER
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Old Dec 25, 2006 | 08:21 PM
  #2  
SCCA RX7 RACER's Avatar
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Gen 2 Raced Hard NA 13B
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From: Canada
Smile 2 Weeks No Reply

No red flags came up to my question, in the past two weeks I feel safe in assuming that the problem I had was just a faulty transistor. So we’ll close the book on this one. I’ll find out in about two months at my first race in Seattle (Short 4 hour endurance race). It’s not for points only to test and have some fun.

Thanks All.
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Old Dec 25, 2006 | 10:48 PM
  #3  
muythaibxr's Avatar
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From: Maryland
Yeah, I think nobody answered because you had most likely already figured out the problem.
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Old Feb 22, 2007 | 03:09 PM
  #4  
SCCA RX7 RACER's Avatar
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Gen 2 Raced Hard NA 13B
Tenured Member 05 Years
 
Joined: Apr 2006
Posts: 272
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From: Canada
Smile Q15 Transistor

Tested the race car on the weekend runs sharp no drop out at secondary transition.
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Old Feb 22, 2007 | 05:17 PM
  #5  
T2GTUS's Avatar
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From: LA, CA
Great news! (faulty parts are everywhere it seems)
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