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VMSpc showing engine voltage variations

July 09, 2012, 11:56:20 am

Sat on our drive to Northern Mich, about 2 hours into the trip the VMSpc started to show the battery voltage dropping from 12.8-12.9 to 11.2-11.4 and back up. This keep up for the next 2 hours.
The Audit monitor showed 12.5 (house battery) and the dash showed 12. Never really moving much as the VMSpc jumped around.
We had both the dash AC running along with the gen and roof AC on. Switching the Boost on/off didn't seem to make any difference.
Didn't feel any difference in engine performance.

Did have the VMSpc interface updated before this trip.

Any clues?

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Re: VMSpc showing engine voltage variations

Reply #1 – July 16, 2012, 12:44:44 am

Do not have the vmspc yet but those voltages are low just based on our 2001 coach.  My audit monitor ranges 13.3 - 13.7.  The dash gauge stayed at 13.  Cranking with boost, the dash did not drop below 12

Mike

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Re: VMSpc showing engine voltage variations

Reply #2 – July 16, 2012, 08:37:32 am

Dick,
Sounds like you need to have the "VMSpc interface updated before this trip" looked at again.  If this is the only change since your last rip, that's where I would start.  Secondly, why did you have the VMSpc interface updated?
Just a thought.
Peter

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Re: VMSpc showing engine voltage variations

Reply #3 – July 16, 2012, 09:15:30 am

I had some problems with my VMSpc last month.  Two of the calculated values (torque and horsepower) quit working.  I called Silverleaf and the guy told me to reset the engine choice.  I did that and it cured the problem.  I too installed a new EXE file for Silverleaf so I could get retarder temps.  I think I forgot to designate the engine when I did that.

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