Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   MEGAsquirt (https://www.miataturbo.net/megasquirt-18/)
-   -   D10 blown, I need help (https://www.miataturbo.net/megasquirt-18/d10-blown-i-need-help-60253/)

absRTP 09-06-2011 03:01 PM
D10 blown, I need help
 
-

Braineack 09-06-2011 03:04 PM
D10 is on the 5V power circuit... you have short between 12v and ground.

c11 is on the crank signal input...maybe that's where the 12v is coming from? bad jumper? check r13. check between c11 and the opto, and check between c11 and optoout.

absRTP 09-06-2011 05:06 PM
-

Matt Cramer 09-07-2011 11:09 AM
The most common cause of continuity from 5 volts to ground is a blown D19.

absRTP 09-07-2011 01:02 PM
-

absRTP 09-08-2011 01:07 PM
-

absRTP 09-08-2011 01:13 PM
-

Braineack 09-08-2011 01:18 PM
it'll be close. it appears that would be the diode that protects from any flyback on the VCC. so if it ever spikes above 5.1v it'll clamp to ground. doesnt leave a lot of room for tolerances...

absRTP 09-08-2011 01:22 PM
-

Braineack 09-08-2011 01:27 PM
Honestly, I dunno.

absRTP 09-08-2011 01:34 PM
-

Matt Cramer 09-09-2011 09:43 AM
Originally Posted by absRTP (Post 769036)
Obviously, I took of D19 and put a 1N4733A in place to test it and finally, there is no more continuity between ground and 5V.

Now, I don't want to powerer it up until someone tell me it's safe to do so with a 5.1V zener instead of a 5.6V one.

Thank you all!
It isn't safe, at least not for that diode (the rest of the MS would be fine). If that zener diode's tolerances are a little off, you could have a 4.9 volt zener in there. Going the other way, to a 6.2 volt zener, is perfectly acceptable.

absRTP 09-09-2011 09:52 AM
-

absRTP 09-12-2011 03:44 PM
-


All times are GMT -4. The time now is 06:13 AM.


© 2024 MH Sub I, LLC dba Internet Brands