Cummins isl 400 wouldnt start

[fidget]

Recently went to start my 2005 Itasca Horizon after it had been parked overwinter near Boston.
Ran perfectly when parked in 2006 fall,and the batteries were fine,but it would not start.Had to be towed to a Cummins shop where the ecm was replaced and reprogrammed
This event has rather scared us as you can imagine since even Cummins have no idea what might have caused the failure in a parked coach
Any suggestions ,information or comment would be really appreciated

[fidget]

Recently went to start my 2005 Itasca Horizon after it had been parked overwinter near Boston.
Ran perfectly when parked in 2006 fall,and the batteries were fine,but it would not start.Had to be towed to a Cummins shop where the ecm was replaced and reprogrammed
This event has rather scared us as you can imagine since even Cummins have no idea what might have caused the failure in a parked coach
Any suggestions ,information or comment would be really appreciated

[vicsryd]

Hi fidget. Long time no see. Sorry your season is starting out rough.

For your long storage period do you use a battery disconnect for the chassis/engine battery or is it being charged continuously with a Trik-L-Charge or Echo-Charge? The battery disconnects became standard on the 2006 Winnebago/Itasca DP's but for 2005 you'd have had to add your own.

There are two things I've heard of to cause for ECM failure (Cummins or CAT) for a parked coach.

One is the chassis/engine battery gets below 6.5v for an extended period of time. Apparently this can cause the ECM to lose it's mind whereas zero volts (battery disconnected) is okay.

The other is some kind of electrical spike may across the chassis may have occurred. Lightning and arc welders have specifically been cited for this. The lightning doesn't have to be a direct hit. A nearby ground strike can cause a ground wave that could jump to the chassis quite easily.

[fidget]

Thanks vicsryd.The battery isolator for the chassis was off,for some reason our 2005 has a factory fitted switch.The battery was kept charged periodically but i guess could have gone sub 6.5 volts at some stage.Ive been wondering if the ecm has an isolator bypass.,to keep it powered
Either way the lack of other responces to my post, other than your very helpful one, makes me think this occurence aint too common which is some relief believe me!

[vicsryd]

Your coach must have been a late model '05 if it equipped with the Guest chassis shut off. If it was off then the ECM should have been isolated from the battery and low voltage wouldn't have mattered.

Thinking about it more an externally induced electrical spike would have probably caused other problems with the likes of tranmission control module, etc.

Who knows, maybe it was gamma rays (aka a stray proton).