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What tool to diagnose CEL on a 400 Cummins

December 08, 2020, 11:43:24 am

On the most recent journey I noticed a CEL and the associated annoying buzzer for most of an 800 mile trip.

Started after about 50 miles, so I pulled over checked all vitals (all good) shut down, and resumed....shortly after (25 miles )the same?

This continued on and off (mostly on) for the rest of the trip, as luck would have it I stopped in to fill up my propane about 30 miles before our destination, and the CEL was off the last leg.

Q. Is there a tool that I can by to look at codes (assuming they are stored) We're set for the winter at our Escapees lot in AZ.

Thanks, Paul

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Re: What tool to diagnose CEL on a 400 Cummins

Reply #1 – December 08, 2020, 12:07:47 pm

Expensive to buy the software, adapters and laptop.. I have one with about 1k invested in Cummins, Detroit, and Cat software.. Typical truck shop charges $100.00 to plug in and read codes.

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Re: What tool to diagnose CEL on a 400 Cummins

Reply #2 – December 08, 2020, 12:41:21 pm

VMSpc will record, save and display any engine or transmission code in real time or in some versions when you click on the diagnostics menu.  And you get all of the other benefits as well.

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Re: What tool to diagnose CEL on a 400 Cummins

Reply #3 – December 08, 2020, 12:58:18 pm

The local Cummins dealer will read and clear codes at no charge.  Not a good option since you are settled in if the objective is to read them without leaving the lot.

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Re: What tool to diagnose CEL on a 400 Cummins

Reply #4 – December 08, 2020, 01:02:08 pm

I have a 96 Cummins that is not electronic controlled. If I had newer I would have the VMS.  Like Roger says it does what a portable scanner like we use in our shop does plus more.

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