Harley Davidson Street Forums banner

1 - 6 of 6 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
I just got a 2015 xg street 500 with 1152 miles on it. When riding it the first time the engine light came on at 40mph. Drop below 40 and it goes away. Resume speed of 40mph or over and light comes back on. Go under 40mph and it goes out. Will sometimes flick on and then off but will light up and stay at 40mph+.
 

·
Super Moderator
2016 Harley-Davidson Street 750 in Sunglo Velocity Red
Joined
·
614 Posts
Heather, welcome to the forum!

What would be helpful is if you could get a mechanic to check the code that it throws to trigger the check engine light. That should be stored even if the light goes out. Without that error code, anybody is just guessing about the cause.

Is it truly speed driven or RPM driven? If you stay in second gear instead of upshifting normally will the check engine light come on at a lower speed? Similarly if you get over 40 mph, disengage the clutch and let the engine idle will the check engine light go out before coasting down to 40 mph?

Have you noticed any roughness in the engine, especially at idle or in first gear?
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #3 ·
Is there a way for me to pull the codes? I tried pressing the odometer reset method and it didn't work.
 

·
Super Moderator
2016 Harley-Davidson Street 750 in Sunglo Velocity Red
Joined
·
614 Posts
I believe the odometer reset method only works for the XG series bikes from 2017 onward. I would appreciate it if somebody with one of the later model XG's could confirm that. I just know that it doesn't work on my 2016 Street 750.

On the earlier bikes you can read the code through an EFI tuner or a dedicated code reader. The tuner that I have and know anything about is the Vance & Hines Fuel Pack 3. The dedicated reader that I know of is the Vance & Hines Code:REaD, which is basically an FP3 with no ability to write to the engine control unit (ECU) other than to clear error codes.

An EFI tuner is a useful but pricey tool, starting from about $350 from online discounters. Tuners record the VIN of your bike and "marry" to that one bike forever, but you can use it on that one bike any number of times.

The Code:REaD is relatively inexpensive with a list price of $99 and you can use it on other bikes as it does not marry to your bike's VIN.

Our bikes have 6-pin onboard diagnostic connectors whereas some of the older bikes have 4-pin connectors. Some devices like the FP3 and Code:REaD come in different models to handle the different connections. For others, such as the H-D Screamin' Eagle Pro Tuner, you buy the tuner and the correct set of cables needed to connect to your bike are a separate purchase.
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #5 ·
De
Heather, welcome to the forum!

What would be helpful is if you could get a mechanic to check the code that it throws to trigger the check engine light. That should be stored even if the light goes out. Without that error code, anybody is just guessing about the cause.

Is it truly speed driven or RPM driven? If you stay in second gear instead of upshifting normally will the check engine light come on at a lower speed? Similarly if you get over 40 mph, disengage the clutch and let the engine idle will the check engine light go out before coasting down to 40 mph?

Have you noticed any roughness in the engine, especially at idle or in first gear?

Definitely speed driven. Gear doesn't matter. Let go of the throttle and light stays until it's down around 35-40. No difference in engine at all.
 

·
Super Moderator
2016 Harley-Davidson Street 750 in Sunglo Velocity Red
Joined
·
614 Posts
I really had no hunches, but was hoping your response would trigger something. No such luck. I really only have my past experience that most of the check engine light problems I have encountered are either a misfire on one or more cylinders or a bad sensor.

Without knowing the diagnostic code, my best guess is that it's ignition related and the bike is suffering an occasional misfire that you aren't feeling or hearing.

Here are some troubleshooting steps that you may already be familiar with:
Having the shop manual for your bike would be really handy if you are going to go into some of the more complex steps. Other tasks such as visually inspecting the plug wires or even pulling a plug wire and checking for spark are pretty straight forward.

I'm a little uneasy suggesting that you dive into all of this as you would have mentioned feeling the engine miss and not just the engine light coming on. I'd feel a lot better about it if we had a diagnostic code indicating "Rear Cylinder No Combustion" or "Front Cylinder Combustion Intermittent".

All Harley Davidson Diagnostic Codes
 
1 - 6 of 6 Posts
Top