Shut off while driving, no power to the ignition?

1996 GMC JIMMY
280,000 MILES • 4.3L • V6 • 4WD • AUTOMATIC
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FISHINMAN1
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  • 3 POSTS
Was driving truck shut down like it was turned off. now no power to ignition but have power to all accessories but no power to starter. I don't even hear fuel pump engaging.
May 25, 2021 at 2:33 PM
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KASEKENNY
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I suspect we have a fuse that is blown to the VCM or the VCM itself is the issue.

We need to start with checking the fuses for the ECM Batt in the IP fuse box (fuse 9) and then the ECM Ignition Fuse (Fuse 10).

I attached the info on this. Below.

The next thing is to check the crank sensor but this is not going to cause the fuel pump and starter to not engage, so I suspect it is a fuse issue or the VCM itself.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Let's run through this info and let us know what you find. Thanks
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May 26, 2021 at 11:24 AM
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FISHINMAN1
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I hot wired it and it started and ran fine fuses are good so computer?
May 26, 2021 at 4:15 PM
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KASEKENNY
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Just to be sure, you hot wired to the ignition and it ran? So you applied 12 volts to the coil? If so then yes, you appear to have just taken place of what the VCM is supposed to do. So if it were me I would put a VCM in it.

I attached the process below to replace it. Please let us know if you have questions on this. Thanks
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May 27, 2021 at 8:27 PM