HID problems with Canbus Harleys
This is a system that I have been dealing with for years on European bikes. It is a sophisticated system that runs most circuits through an electrical controller ECU. The ECU monitors the current flow on all circuits and, if it detects a problem like a short or a drop in power usage, it will shut down that circuit. There are no traditional fuses.
If the ECU intervenes because it detects a problem, it will do so and send a "fault code' message to your ECU read-out to tell you what the problem is.
It can be a pain in the tail. You can no longer make accessory changes to the electrical system with allowing for the ECU monitoring everything. As long as you use OEM plug and play accessories or aftermarket accessories that are Canbus friendly, you will have problems.
If you use anything not Canbus-friendly, you'll have to make arrangements to circumvent your Canbus system through an accessory power panel or to adapt your accessory to fool the Canbus ECU into thinking everything is okay and current load has not changed on the circuit you are modifying.
I recently decided to replace my H-D Daymaker LED headlight with an HID unit on my 2012 Super Glide Custom. LEDs have made tremendous improvements but the Daymaker just doesn't put out the volume of light that I experience with an HID conversion.
So, I wired everything up just like I have done with older non-Canbus bikes but I encountered problems. When I switched to high beam, the high beam would flip on momentarily and then flip off. I spent time tracing everything down thinking that I had a dead short someplace but discovered that, even with the head lamp connector plug removed from any connection, I still had the bike not holding high beam.
I then remembered that I am dealing with a Canbus bike. AHA!
I correctly surmised that there was too light of a load from the new HID lamp on high beam and the ECU was thinking something was wrong and shutting it down. The HID bulb usually pulls about 35 watts compared to a stock halogen pull of 55-60 watts. The circuits on a Canbus bike are controlled by the ECU. There are no fuses.
The solution is to install resistors, often called "load equalizers" on the offending circuit to make the circuit use the amount of voltage that the ECU is looking for.
Luckily, I was also planning to install a pair of LED auxiliary lights that I was going to wire onto my high beam circuit. This would also produce an extra load on the high beam circuit that may get the power usage of that circuit up closer to what the ECU is looking for and maybe make it hold the high beam on for both the HID lamp and the auxiliary LEDs.
Once I wired up the LED auxiliaries, they worked and, indeed, they added enough electrical draw to the high beam circuit to make the ECU think everything was okay and keep the circuit on.
If any of you have this sort of problem with a Canbus bike, just go to Radio Shack or an auto parts store and get some resistors (usually 5-6 ohms) and connect them from the positive wire of your offending circuit to ground to make that circuit use more power and trick the Canbus controller ECU to thinking that everything is okay.
It's ironic that the Canbus system, left alone, prevents you from taking advantage of LEDs and HID lighting to reduce the current draw on your charging circuit. My understanding is that H-D has a modified Canbus system for turn signals and tail lights that allow LEDs without using resistors to make the load resemble incandescent loads.
If you have a problem, though, check your current loads and be sure the accessory is drawing a pull similar to the stock loading that the ECU is looking for.
Last edited by leafman60; Dec 12, 2016 at 08:52 PM.
LEDs have made tremendous improvement and they are much simpler and easy to install than a bulky HID system. However, at least in many cases, the HID system dispenses more light and they draw only about 35 watts. Of course, the reflector has a lot to do with distribution of that light but, fact is, I have experienced better luck with HID- in the Super Glide and other lamp assemblies.
I have several bikes. Some have LED head lamps, some have HID and some have halogen. The HID still trumps LED in most of my applications.
As I said in my original post, I had the H-D Daymaker LED head lamp in this particular bike. However, it is far inferior to the light I get from an HID in the same bike.
If you like LED and think it's the bee's knees, great. My experience has been that such is not always true. Also, unless the LED head lamp is Canbus friendly, you will have the same problems mentioned above.
Last edited by leafman60; Dec 12, 2016 at 08:55 PM.
Maybe they have a Canbus over ride for low beam. The problem is when switching to high beam. Other than powering the same HID bulb, high beam adds the draw of the solenoid that pulls the bulb in the reflector to change its position and the reflective direction of the light.
Adding a little more load to the high beam circuit with the aux lights (led) fixed the problem for me.
Last edited by cvaria; Dec 12, 2016 at 03:15 PM.
Additionally, at one point in the past I installed a H4 HID kit (canbus compliant) in a 5.75" HD factory reflector, and while it definitely looked brighter looking at the headlight (Lots of scatter) the light it put on the road was not as bright or defined as the daymaker I had previously installed. And the (high-low servo worked too...) Loving my current JW Speaker adaptive LED...
Last edited by Mchad; Dec 13, 2016 at 12:27 PM.
Trending Topics
The Best of Harley-Davidson for Lifelong Riders
Ghost










