ECM code being thrown due to altitude

[Jack Klarich]

Good deal

[520fd]

I was riding in the Needles Highway in South Dakota during Sturgis. Not sure what the elevation was. Was driving pretty aggressively, Got an engine code. Took it to Black Hills HD. Spent 3 1/2 hrs. waiting for it to get fixed. When I checked out they told me I had a PO 152 code. They ended up replacing the rear o2 sensor. Seemed to fix the problem. Never acted up again. But after that, I was never in the elevation again.

[Capt.Bob]

On my 2017 M8 TGU, about 200-300 miles after performing my 5000 mile service, my trike started throwing the PO152 code but it was essentially near sea level in North Florida. A Tallahassee dealer got the rear O2 sensor in and they replaced it under warranty. The engine has not thrown the code after replacement of the rear O2 sensor. I kept clearing the code and it would sometimes take 30 minutes to throw the code and sometimes it would be thrown just after startup on a couple of rides to get the problem resolved from a dealer who had the sensor to replace the bad one. The Service Writer said that they had experienced a number of the O2 sensors being sensitive and essentially quitting or intermittently working. About 2500 miles after the rear O2 sensor was replaced, I have not had another code thrown for the O2 sensor.

[ISP-FL]

My winter riding buddy has an early 2017 TG M8. Not sure what code he has gotten but two times he has been in higher elevations (once in SD and once in TN) he has gotten them. Dealer he went to said not to worry about it just to keep on riding and see what happens!

[Jack Klarich]

Looks like HD got a bad batch of O2 sensors

[Jack Klarich]

My winter riding buddy has an early 2017 TG M8. Not sure what code he has gotten but two times he has been in higher elevations (once in SD and once in TN) he has gotten them. Dealer he went to said not to worry about it just to keep on riding and see what happens!

Joe, tell your budddy to record the codes and have the dealer made aware of them

The ECM knows there is some thing out of parameters and can only fix what it has in its parameters

Clearing the codes with out fixing the underlying problem is sure to cause more problems maybe even a failure of components JMO

It is not normal or OK for these codes to keep coming back

As long as your buddy keeps HD in the loop I am guessing they cannot hold him hostage should a major issue rear its ugly head

I would not tell someone not to worry about a check engine light or multiple codes, but that is just me

I have seen bad Ju Ju happen because of this same thing JMO

[FuzzyWuzHe]

This is an update on my friends 2018 TriGlide that was throwing codes when he went up in altitude, usually above 7,000'. It stopped doing it!! He's still waiting for the new download from H-D, but for now it's not throwing anymore codes. Over time the codes were thrown less and less and the light stayed on for less and less time the more times it happened. No one seems to know why except that maybe it's "learning" better? Anyway, wanted to let you know what's been going on with this problem. I still have not had any codes thrown at altitude on my M8, so that's a good thing.

I would bet that the ecm has slowly over time adjusted to O2 sensor ... and I'd almost bet, at some point the O2 sensor will fail miserably.

[mjconde]

A friend of mine just bought a 2018 TriGlide and now both times he's ridden it up into the mountains, it's throwing an ECM code. He talked to one dealership and they said it is a known problem with altitude and the ECM. The trike is set so lean that the rear cylinder isn't running right (?). Not positive on all the particulars, but he keeps getting the same code show up. They said they're pretty sure he'd be fine to just ride it, but he's worried about getting stuck up in the mountains and needing it towed if it stops running.

Has anyone else heard about or experienced this problem?

Side note: I bought my new 2018 the same week from the same dealership and have not had the problem....yet.

I do not have this problem with my 2014 Triglide and I live at 6400 feet and have to cross a pass at 7600 feet when ever I drive out of the Scarmento Mountains to las Cruces. Been here 4 years without this problem. I actually get better fuel mileage up here vs. Fort Worth, TX where I bought the bike.

[GoSlo]

Just an update on my friends '18 TriGlide throwing codes at altitude.

He rode up in the mountains last week and the light came on again with the same code so he took it back in to the dealership. This time they talked directly with Harley and they agreed to change out the rear O2 sensor, plus an o-ring. So now he has to head back up and see if it's fixed or not.