Boost control circuit

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rickb794
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Joined: Sun Dec 21, 2008 10:28 am
Location: Portland OR

Boost control circuit

Post by rickb794 »

MS2 357 built by Context Eng.

Had a DIY kit in for boost control.

In testing the solenoid would activate but not release.

Switched the transistor out to a TIP122 per the manual.

Same results, the solenoid energizes but will not release unless the switched side is opened.

In test mode with output turned on I removed the JS11 trigger connection and the solenoid still does not release.
Removing the JS11 connection and grounding the base does not release the solenoid.

Only opening the solenoid circuit will release the solenoid, voltage reading on the switched side with the output off is 1.3v.
Once the solenoid is energized it will not release.

I even tried inverting the output but that was already proven to not be the cause as I lifted the JS11 trigger from the output transistor.
And grounding the base had no effect.

The last thing to check is ohming it out to ground with the solenoid and the MS unplugged, to make sure there is no leakage there.

Also this is the same install (not mine) that I have been trying to solve an idle stepper issue on.
http://www.msextra.com/forums/viewtopic ... 01&t=67632

I am loosing this battle & need backup!
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Read the Do's and Don'ts to avoid the common pitfalls before starting your install or asking for help
Use only these manuals other manuals may cause brain damage or worse.
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