ISC & Code 37

[Northernboy]

Just worked on a Nytro that was giving Code 37, turned out to be a grounded wire but while troubleshooting the ISC motor was removed. The service manual says do not remove it and the whole throttle body needs to be replaced but I found it can be removed and tested. Also all years don't list a P/N except 2008. the P/N is 8GL-13713-00-00. The motor can be removed and tested using diagnostics 54, the shaft should move in and out.
This is just information for anyone having issues with code 37 or high idle.
Good Luck

 

[yamariv]

Thanks for the heads up! Someone will need this info in the future for sure. That's why this forum is great!

 

[Dr. FeeLGooD]

My 09 Nytro xtx shows fault code 37. I have tested the motor assembly (part 15) with Diagnostic code 54 and it seems to be moving in and out properly but there is periodically a clicking sound ( like a plastic gear skipping)that comes and goes from the assembly while the sound of the motor turning stays constant. Maybe what my trouble is. (High idle) For me a confusion is throttle sensor assembly (part 23). I was under the assumption this part is what fault code 37 refers to and maybe there is something wrong with that?


.https://www.shopyamaha.com/parts-catalog/parts/snowmobiles#/Yamaha/FX_NYTRO_-_FX10XL_-_2008/INTAKE_2

 

[Dr. FeeLGooD]

I was convinced the issue was the motor assembly on the throttle body. I switched them from my 09 to my 10 and vice versa but my 09 still has high idle and code 37 while my 10 stayed normal. Even after letting them warm up to normal operating temperature. So I can rule that out. I was told to adjust my min idle speed but pretty sure there is no adjust for that? I think the guy who told me that is stuck thinking about turbos and perhaps turbo sleds have an idle adjust? I guess I will start searching for a bad ground. Anyone know how many grounds there are and where to look? Any suggestions at all? I have been searching code 37 and high idle but lots of dead threads with no solutions yet. It is starting to get cold out and hopefully I will be ready when the time comes.

 

[Dr. FeeLGooD]

Traded ECUs across my two Nytros. Didn't want that to be the problem but happy I found it. Heading over to the wanted section.

 

[Dr. FeeLGooD]

Nope, not ECU. I started the sled with the "bad" ECU and the code cleared. Was poking around and found a rub through on the main harness near the engine. Fixed that and it idles beautifully! Good thing I haven't found an ECU yet. Next is track and drivers and shock rebuild.

 

[jimbur]

What area was the harness rubbed?

 

[Dr. FeeLGooD]

I have K&N filters and over the years I likely missed a zip tie or two. The harness settled down against a nub on the motor mount.

 

[grizztracks]

 

[Dr. FeeLGooD]

That's it! Was thinking about grinding it off. One tiny little wire was broke right through, a large white wire was wore half through and a large pink wire was barely nicked. Sure happy the repair cost me nothing compared to an ECU. I wanted to take this thread right to the end because there is not much info that I could find on this topic. If someone has a link to how to properly repair a rub through that would be cool too. Thanks for the pic Grizz.

 

[AftonJay]

Which side is that, clutch or brake? I get the 37 code once in a while as well although mine idles fine and when I do diagnostic 54 I hear it vibrate/cycle. So maybe it is just starting to rub through or something, hopefully.

 

[grizztracks]

This has been a known issue with the first few years of the Nytro. It on the clutch side behind primary.

 

[AftonJay]

Thanks Grizz I will check it out.