If your Harley cruise control has an issue, there is an interactive cruise diagnostic test that can be performed on the motorcycle without the need or aid of any diagnostic service scan tools or computer.
The Harley cruise control function is governed by the motorcycle’s ECM. The ECM monitors the vehicle speed sensor (VSS) to establish the bike’s current speed. The ECM then modulates the throttle control actuator to maintain a constant vehicle speed. When cruise control is enabled, the orange cruise lamp will change to green. The ECM monitors the engine RPM and the output signal from the vehicle speed sensor. Then, the ECM signals the throttle control actuator to open or close the throttle to keep the speedometer output speed signal constant.
The ECM will automatically disengage an active Harley cruise control mode if it receives one of the following input signals:
– Front brake is applied
– Rear brake is applied
– Throttle is rolled forward (throttle roll off/ cruise disengage command)
– Clutch lever is engaged
– Wheel slip is detected (an ECM detected jump in RPM)
– Pressing cruise switch
– SET/- switch is held in until the motorcycle speed drops below thirty miles per hour
– RESUME/+ switch is held in until motorcycle speed goes above ninety three miles per hour.
Bob and Mark give us a sequence demonstration for entering and moving through the cruise diagnostic mode. The illuminated amber/orange cruise light changes to green for every tested function.
If your Harley cruise control is not functioning correctly, you may have one of the following conditions to pursue:
– Throttle position faults P0120 & P0220
– Vehicle Speed Sensor faults P0501 & P0502
– Cruise control switch failure
– Front or Rear brake switch failure
– Throttle position error P2135
– Flash memory error P0605
– ETC limited performance mode
The most common reason for inoperative or intermittent cruise failure is from a broken or misaligned front brake switch. If your cruise is not working, look behind you. See if your brake light is stuck on. Could be an easy fix.
I have a 2008 Ultra and this procedure doesn’t seem to do anything on my bike. What years is this procedure good for? (When I hit a series of mild bumps my cruise kicks out, and I get both front and rear break error codes. The dealer has no clue)
The brake error codes should be leading the dealer to the root of the issue.
These errors are the reason for your cruise control issue.
Typically a tech should be able to look up a code and follow a flow chart in the electrical manual for your year & model to come up with a definitive diagnosis.
https://www.fixmyhog.com/post/videos-harley/
Hello Rick,
The brake error codes should be leading the dealer to the root of the issue.
These errors are the reason for your cruise control issue.
Typically a tech should be able to look up a code and follow a flow chart in the electrical manual for your year & model to come up with a definitive diagnosis.
https://www.fixmyhog.com/post/videos-harley/
You’ve already diagnosed your cruise control issue; there is something wrong in your brake light circuit. That is what you need to diagnose. Inspect function of your front & rear brake lights.
Make sure that your front switch is not sensitive. If the brake light can be triggered by vibration, it will cancel your cruise. This is common with aftermarket levers or if the front switch has become damaged.
https://www.fixmyhog.com/video/how-to-replace-brake-light-switch-on-a-harley-010885/
https://www.fixmyhog.com/video/how-to-test-a-rear-brake-switch-001635/
Thanks,
Mark FMH Video Membership
Recently I had an issue with cruise control on 2017 Ultra Glide when the gear position indicator developed a fault. The display would no longer show which gear the bike was in. It would only display a neutral light and when riding cruise control could not be activated. It was only fixed after the sensor was replaced. Just some fyi. Nice site btw..