Resolved. I have a scangauge code Cummins doesn't recognize.

[John___Angela]

SO. Got my scangauge to check out the check engine light code on my ISC350 CAPS. The code is ID 18 and FM 11. Talked to Cummins and they could only suggest I take it to a Cummins dealer, which I will, probably in Vegas.

Also the code clears but the light doesn't go out. Having said that the code comes back pretty quick after so it might be a continuous thing.

The motor starts and runs fine. We are not stranded but I am fairly convinced it is de-rated as it seemed fairly gutless on the hills up at 8400 feet in Bryce.

Below is the resolution but it is also repeated in a later post.

OK. In keeping with my promise to post the resolution, here goes. We quite honestly have been busy with other things so I haven't had a chance to look at this problem. But we are on the road trip again in a few weeks so I thought I would give it a shot before taking it to Cummins.

So a little history. My seargent major told me a long time ago to always record the readings meters and indicators on equipment when things are running well. That way when things are not running well you can see whats changes. You won't remember or recognize subtle changes when things deteriorate. To that end, 11 years ago when we bought the coach I took a permanent marker and marked ALL the gauges on the dash as well as took key point specific readings of various values and marked various areas with a label maker for what are normal values in specific operating conditions. So, when the alternator voltage started to slowly drop over the last year I wondered what was happening. On the last trip the voltage was down around 12.9 on the meter although STILL READING OKAY DIRECTLY ON THE BATTERIES. Probably because of the solar array. Who knows. Anyway. Today I got under the bed and went straight for the alternator connections. One of the connections (found out it was the positive when the sparks flew after grounding the wrench) was corroded. It was tight but I mentioned to loosen and clean it somewhat and re-tighten it. (It still needs a better cleaning) Fired it up, noticed the voltage on the meter back to where it is marked from 11 years ago, tried to clear the code with the scan gauge AND THIS TIME THE CODE CLEARED AND THE LIGHT WENT OUT. I'm not happy with the posts on the alternator and it need to be completely removed cleaned and put back in but this should hopefully solve the problem in the meantime. I'm recovering from an injury and didn't want to spread myself out on the engine any more than I had to.

Hope this helps the next guy.

Cheers.

[John___Angela]

wa8yxm wrote:
You might try somehting like dielectric (non-conductive) grease on the posts after tightening.

True story: Used to have a car that would start sometimes, and sometimes if you tried to restart it (Say after buying gasoline) no joy.

Turns out the alternator casing was not properly grounded, That's right, those big well greased bolts were not making contact,, I removed one slipped a star washer under it and all was good.

The dialectic grease is a excellent idea. Thanks.

[wa8yxm]

You might try somehting like dielectric (non-conductive) grease on the posts after tightening.

True story: Used to have a car that would start sometimes, and sometimes if you tried to restart it (Say after buying gasoline) no joy.

Turns out the alternator casing was not properly grounded, That's right, those big well greased bolts were not making contact,, I removed one slipped a star washer under it and all was good.

[John___Angela]

OK. In keeping with my promise to post the resolution, here goes. We quite honestly have been busy with other things so I haven't had a chance to look at this problem. But we are on the road trip again in a few weeks so I thought I would give it a shot before taking it to Cummins.

So a little history. My seargent major told me a long time ago to always record the readings meters and indicators on equipment when things are running well. That way when things are not running well you can see whats changes. You won't remember or recognize subtle changes when things deteriorate. To that end, 11 years ago when we bought the coach I took a permanent marker and marked ALL the gauges on the dash as well as took key point specific readings of various values and marked various areas with a label maker for what are normal values in specific operating conditions. So, when the alternator voltage started to slowly drop over the last year I wondered what was happening. On the last trip the voltage was down around 12.9 on the meter although STILL READING OKAY DIRECTLY ON THE BATTERIES. Probably because of the solar array. Who knows. Anyway. Today I got under the bed and went straight for the alternator connections. One of the connections (found out it was the positive when the sparks flew after grounding the wrench) was corroded. It was tight but I mentioned to loosen and clean it somewhat and re-tighten it. (It still needs a better cleaning) Fired it up, noticed the voltage on the meter back to where it is marked from 11 years ago, tried to clear the code with the scan gauge AND THIS TIME THE CODE CLEARED AND THE LIGHT WENT OUT. I'm not happy with the posts on the alternator and it need to be completely removed cleaned and put back in but this should hopefully solve the problem in the meantime. I'm recovering from an injury and didn't want to spread myself out on the engine any more than I had to.

Hope this helps the next guy.

Cheers.

[John___Angela]

I wanted to update the followers of this thread. We made it safely without incident to our lot in Palm Springs. It will be a couple weeks before I have a chance to continue on with the fault finding of check engine light and the subsequent engine derate. We have some domestic type things to look after over the next week or so and then we'll get back to trying to chase this down. Overall we had a great trip down from the great white north. Everyday is an adventure and we enjoyed the challenges the big guy threw at us along the way.

Now, first priority, stop at Walmart for a case of 1.97 wine.

I'll post back once we get back at it.

J and A

[John___Angela]

So, a little update. Today we ended up leaving Bryce and travelling to Barstow. We had intentions of getting to Palm Springs but had a road hazard incident that you can read about here.

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/28008711.cfm

Alls well on that front.

However, this is what I noticed on the scangauge while on the road.

1. Max boost on the biggest hill was only about 17 PSI. I was expecting around 25 to 27. Yes, No???? I suspect this is a result of the derate caused by the check engine light.

2. For whatever reason the voltage jumps all over the place from 12.5 to 13.6 and all in a matter of a minute...in other words, wild swings in a matter of seconds. Normal??? To add to this, when I pulled into Barstow I took a few minutes while fueling to load test the batteries. Alls well. Quiescent around 12.7 volts and held up well under 20 second load test. (Thats when the meter gets too hot 🙂 ) Also when coach is running battery output reads a solid and consistent 13.9 volts so I think the alternator is fine. Tightened down all connections on the battery. Check engine light still on.

Question. For those of you with the ISC350 or ISL400, when the key is in the on position but motor not running does the check engine light come on?? Ours does. Almost like a sensor is reporting a problem BEFORE the motor is started.

Will call scangauge tomorrow re codes....after we get to Palm Springs. Also hope to check ECM grounding at that time.

Comments welcome. Overall, life is good, had a nice day on the road, took the hills one gear slower and even the slow trucks passed me. Got a little exercise (or at least Angela did) changing a trailer tire and overall we enjoyed a nice sunny day. All tucked in to a Travel America parking lot for the night. Tomorrow is a another great day.

J and A

[Tom_Barb]

John & Angela wrote:
Where would you recommend checking for the ground.

ECM case to engine block. Yes it is mounted directly to the engine block, but our was loose, and did not make ground, and gave us the same symptoms (light and no power) Cummins dealer and service shop said the ECM was bad, because the reader said the ECM had an internal failure. but when you wiggled it the code reader would give different codes as if it were normal. I removed it, cleaned it, and replaced it using star washers under the mount pads and we have had no more problems.

[John___Angela]

rgatijnet1 wrote:
Maybe these links will help: Cummins engine codes
Engine codes
More Codes

Good morning and thank you for taking the time to do this. We'll throw it in with the mix of info we have and see what comes out if it.

When this gets resolved ill post the resolution but just a heads up that may not be till next week.

Thanks again.

[rgatijnet1]

Maybe these links will help: Cummins engine codes
Engine codes
More Codes

[John___Angela]

Tom/Barb wrote:
Easy things to check on a ISC the ECM will loose its ground, make sure it has a good ground, when it does not the engine drops to keep alive data.

be certain you are connected to the engine data plug. not the chassis's

Thanks again for your input Tom. Where would you recommend checking for the ground. Are you thinking a pin on a connector or something more generic like a large connector. I guess I'll have to figure out where the ECM is as well. I'll start snoopin tomorrow.

[John___Angela]

Tom/Barb wrote:

John & Angela wrote:

Tom/Barb wrote:
What code does the onboard computer give?

Hi Tom/Barb and thanks for responding. Umm. I don't know if I have one of those. Do I? 2003 Fleetwood Revolution on Freightliner chassis.

I checked the port at the back and it reads the same error codes.

Can you advance to the next screen ? see what is there? Your codes does not correlate to cummins codes.

are you certain the scan gauge reader will adapt to cummins?

Well, I'm not sure about anything really. There is no next screen. Yep, those are not cummins codes. I'll be talking to scan gauge tomorrow.

[Tom_Barb]

Easy things to check on a ISC the ECM will loose its ground, make sure it has a good ground, when it does not the engine drops to keep alive data.

be certain you are connected to the engine data plug. not the chassis's

[Tom_Barb]

John & Angela wrote:

Tom/Barb wrote:
What code does the onboard computer give?

Hi Tom/Barb and thanks for responding. Umm. I don't know if I have one of those. Do I? 2003 Fleetwood Revolution on Freightliner chassis.

I checked the port at the back and it reads the same error codes.

Can you advance to the next screen ? see what is there? Your codes does not correlate to cummins codes.

are you certain the scan gauge reader will adapt to cummins?

[John___Angela]

moisheh wrote:
J&A: I was having a similar problem and it turned out to be the coolant low level sensor. Amazing at how much power you can lose when it derates.

Moisheh

Hi Moisheh. Good to hear from you.

I have had the coolant sensor go off before. Level is good but I topped it up a bit anyway. I'm not getting the light or buzzer for the coolant. I can try a by pass. If I knew what was reporting it would be a lot easier.

[moisheh]

J&A: I was having a similar problem and it turned out to be the coolant low level sensor. Amazing at how much power you can lose when it derates.

Moisheh