Can High Wattage LED Headlights Cause Error Messages?

[DaniBoy]

At the beginning of the 2023 season, I removed the stock halogen H7 bulbs and replaced them with Fahren super bright LED H7 bulbs that were rated at 65 watts. They worked great, and I had zero problems (no error messages). They were awesome all season (3000+ miles).

Fast forward to 2024. After routine winter maintenance, I’ve had the bike out several times this year already. One day as I pulled into a parking space, I could see my reflection in a plate glass window, and I noticed one of my headlights was very dim. When I got home, I shut the bike down, pressed the manual headlight button on the right-hand grip, and noticed the little cooling fan in the dim light was very noisy, like a bad bearing. I found a set of LED H7 bulbs on Amazon, but these were fanless! I also saw that they were rated at 120 watts, almost double the wattage of my first set. I bought them and put them in.

The next day, I went for my first ride with the new bulbs. I backed out of my garage, went to shift into 1st, and nothing happened. I looked down and had the dreaded “Check Transmission” error scrolling across the dash. I hit the paddle again and the light went out, it shifted into first, and off I went. No errors at all during my ride. I returned home, and while I was making the turn into my driveway, it automatically downshifted into first, then as I was putt-putting along the driveway to my garage, the light came on and the message reappeared (note that the paddle shifter was never even touched). I stopped, shifted into neutral, and the message immediately disappeared. I then shifted into first and pulled into my garage.

I searched for that error on this forum and came up with countless posts on the subject. Most referred to either the paddle shifter itself, or else the gearbox position sensor on the left side of the engine. I pulled the Tupperware and immediately found the plug to that sensor covered in oil. I removed the sensor, pulled the plug, and gave each a vigorous hosing with brake cleaner. After that evaporated, I reassembled everything, and I went for another ride. After I started the bike, I pulled the paddle rearward, only before I could press the R button, the light came on and Check Transmission appeared. I let go of the paddle and it disappeared. So I pulled the paddle again, held it, pressed R, and backed out. I shifted into first and took off. Shifted buttery smooth throughout my ride. When I got home, it automatically downshifted into first, again as I was going very slowly to turn into my driveway. While slowly going to my garage, it once again lit up and scrolled the message (please note that again, the paddle shifter was never touched). This time, I did not stop and touch the paddle, which would have made the message go away. I pulled into my garage and shut the bike off. Then I turned the key back on, and the message was still there. I attempted to pull the code using the handlebar sequence (on my bike, it’s holding the manual headlight switch and the mode button down, while clicking the highbeam flash 5 times). Nothing happened. I shut the key off, waited a couple of minutes, turned the key back on, and the message was gone. I again attempted to pull any codes, and it said, No Active Fault Codes.

So that’s the story. Now to my theory: First, I never had this problem until AFTER I replaced the 65 watt LED's with 120 watt LED's. Second, I know that these early 998s are extremely sensitive to voltage. Low voltage can generate false errors. I also know there’s no alternator, only a magneto, which, as I understand it, must be driven fairly fast to accomplish its job of keeping the battery charged (not like driving very slowly in a driveway). My question, is it conceivable (or even likely) that 120 watt headlights draw more power than what the system can handle, thus “starving” the computer of power, thus causing a false error? This problem has never happened while shifting at road speeds, only while sitting still, or driving very slowly after an automatic downshift into first.

Sorry for the long post! I just wanted to provide as much information and detail as I could.