Well - my ignition saga goes on & I thought I'll go back to basic and test the VB921's - apply 5V via 330ohm to pin 1 and see if pin 2 & 3 have continuity.
What was working last night is now not working. Pull out a new VB921, did the test - worked. Fiddle with the board. Went back to test the new VB921. Now it is NOT working - no continuity.
Did I do something wrong or are these really that finicky?
I am stumped... and please tell me I should not give up
How tolerant is VB921?
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Checking for continuity isn't how I would test it. Apply a decent load to it - like a car light bulb or similar. i.e. +12v -> bulb -> VB921 -> ground
Then apply 5v to the base.
James
Then apply 5v to the base.
James
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James, you are right - must be too late last night. Zero load may not work.
And yes, just confirmed that I did have 2 dead VB921 that corresponds to me not seeing spark from those 2.
THANKS!
Now looking forward - how do I "debug" starting problem if I have fuel & spark and car won't start? Where do I look - MT? MSLVV? ???
And yes, just confirmed that I did have 2 dead VB921 that corresponds to me not seeing spark from those 2.
THANKS!
Now looking forward - how do I "debug" starting problem if I have fuel & spark and car won't start? Where do I look - MT? MSLVV? ???
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If you have fuel and spark it is back to the basics like trying to start any car. Is the spark happening at the right time - test with a strobe. Are you getting the right amount of fuel? Check plugs to see if they are wet fouled and/or try some easy start spray.
James
James
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How tolerant is VB921?
If you think you might have damaged a VB921 but it still
seemd like it's working... an ohmmeter CAN be used to
check them. From Base to drain you'll see less than 100K
ohm if its bad or damaged. If good, it'll read >80
megaohms
btdt. YES...you CAN statically zap the base inputs.
They'll still trigger, but not at full power.
ptegler
On Wed, 02 Aug 2006 04:33:11 -0700
"jsmcortina" <jsm@jsm-net.demon.co.uk> wrote:
ptegler@cablespeed.com
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seemd like it's working... an ohmmeter CAN be used to
check them. From Base to drain you'll see less than 100K
ohm if its bad or damaged. If good, it'll read >80
megaohms
btdt. YES...you CAN statically zap the base inputs.
They'll still trigger, but not at full power.
ptegler
On Wed, 02 Aug 2006 04:33:11 -0700
"jsmcortina" <jsm@jsm-net.demon.co.uk> wrote:
Paul TeglerChecking for continuity isn't how I would test it. Apply
a decent load to it - like a car light bulb or similar.
i.e. +12v -> bulb -> VB921 -> ground
Then apply 5v to the base.
James
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