Cummins QSB Low Battery ECM Voltage

[Andy Novey]

Pair 425 QSB’s with SC V1 and a VV4 display.   I had an electrical problem in the boat hangar and I lost power while I was out of the country and the batteries died.  I have charged everything  up and the batteries are fine and hold their charge and I  don’t see any issues but I have a persistent low ECM voltage alarm on both engines which are on separate batteries.  I see full voltage on both batteries and have run the boat for 6 hours straight and the alarm is still there.  Is there anyway to clear this?  I have seen this issue elsewhere on the forum but the issue was never closed out.  Attached is what the display is showing

Topic

[Andy Novey]

I just redid those wires to connect them directly to their starting batteries after having problems with them connected to the main DC panel.  The terminals are clean and show full voltage at the battery and at the terminals on the ECM with my Fluke meter.  I am wondering if even the batteries showing full vooltage they were damaged when they discharged.

[Gene Fuller]

Have you checked the voltage at the engine? There are two special terminals just for the ECM. Use a good digital voltmeter. There could be a wiring problem that does not show up on your helm display.

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Tony Athens

[Andy Novey]

Anybody got any thoughts?

Can’t figure this out.  Still has the code.  Rthe issue. 13.6 v while I am.runninv. 

 

[Andy Novey]

Let me try again. 

[Richard Dodson]

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[Author]

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