Stop Enginge Alarm - Nuisance

[Mnichols4]

On occasion when pulling a tough grade I get a stop engine alarm. After about 20 seconds it goes aways and may never reappear for again that day or that trip. When I spoke to the Freightliner people they say don't worry it's just the coolant level sensor and this is very common. I keep the coolant filled and I hate a canned answer, I know this should not be occurring. Is there anyone or has anyone else experienced this and was a solution found?

[srydve]

I have had the check engine light due to low coolant and it is very common, the tank doesn't have to be down very much and it will start on hills. I have also had check engine on long hills and it was also accompanied by a slight loss or hesitation in power. Since the coolant issue I have installed the silverleaf and was able to get the code. Wasn't really much help but it did indicate a fuel problem. After replacing the lift pump and filter didn't fix the problem I replaced the fuel strainer which did. It's a little difficult to locate kind of buried in the wiring loom on top of the frame passenger side behind the rear wheels. It's only a $15 part. Hope this helps, Dave

[jryals]

I had the same problem with the low coolant light. The coolant level was fine and the engine was not overheating. I drove another hour with the light on and buzzer blaring. Finally all the dash gages went dead and the engine died. It cost me over $700 to tow. It’s in the shop now, I’ll let you know the results.

[RickO]

Quote:

Originally Posted by Mnichols4 . When I spoke to the Freightliner people they say don't worry it's just the coolant level sensor and this is very common. ?

It happened to me on the maiden voyage of my brand new coach and I had it towed 40 miles to a Cummins dealer only to find out it was just a bit low on coolant. This happened while starting up the Grapevine grade near L.A.

Good luck...

Rick

[Boris and Natasha]

We had an "intermittent" low coolant warning (with the coolant level AOK, of course) for several months. Our ISL it is programmed to give you about 30 seconds of amber "check engine" then about 30 seconds of red. Then, it shuts down. (That's not much warning.)

The problem was so intermittent that the Freightliner dealer we took it to (for another problem) couldn't find it. The next morning, as we were getting ready to leave, we had the problem at startup. We called Freightliner and the local dealer had a tech on the spot within the hour. He quickly diagnosed the problem.

Turns out it was a coolant level module that was faulty and needed to be replaced. Since then, we've run without that scary warning and shutdown.

Good luck!

[Perry White]

You need to get your ECM updated from Cummins. It is supposed to be a warrantable upgrade. Seems like sensors don't like the new coolants. Since I upgraded mine, haven't had a fault yet. It's not suppose to shut the engine down, at least that's how it is programed in my ISM, just a warning lite.

[MaverickBBD]

Get a print of your ECM next time you are in for service and make sure it didn't go into a de-rate mode. If I remember correctly it shows the log hour of occurrence and temperature.