Author Topic: AK 550 weak fob battery  (Read 6153 times)

Hornblower

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AK 550 weak fob battery
« on: September 23, 2025, 12:29:12 PM »
I've had the AK for a little over a year and it's been just excellent. Yesterday, a strange thing happened. I went out to run an errand on it and it was completely dead. The ignition switch was inoperable. I had two thoughts, maybe disconnect/reconnect the battery (I knew the battery was fully charged) or maybe check the fob battery. There had been no warning about the fob battery so I wasn't sure. The fob battery is a 2450, 3V coin battery. It checked 2.65V so I still wasn't sure that was the problem. Anyway, I put in a new battery and voila, everything came back to life. Happy Day! Lesson learned! Even a somewhat weak fob battery on this bike can leave me stranded! I suppose the smart play is to keep a spare fob battery onboard.

Neil955i

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Re: AK 550 weak fob battery
« Reply #1 on: September 25, 2025, 12:38:40 PM »
The batteries last for years in the manufacturer's packaging Hornblower, so I suppose secreting one on the scoot would be a wise precaution.
Regards & ride safe,
Neil

Current garage:  Kymco DTX360 & Triumph Street Triple 675R
Past bikes: BSA C15. Honda S/wing (GL500). Kawasaki GPz750. BMW K100RS. Kawasaki GPZ900R. Yamaha FJ1200 x2. Sprint. Triumph Daytona 900. Kawasaki ZX-7R. T595 Daytona. Kawasaki ZX-9R x2. Triumph Daytona 955i. X-Town

rjs987

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Re: AK 550 weak fob battery
« Reply #2 on: September 25, 2025, 02:42:36 PM »
I've had the AK for a little over a year and it's been just excellent. Yesterday, a strange thing happened. I went out to run an errand on it and it was completely dead. The ignition switch was inoperable. I had two thoughts, maybe disconnect/reconnect the battery (I knew the battery was fully charged) or maybe check the fob battery. There had been no warning about the fob battery so I wasn't sure. The fob battery is a 2450, 3V coin battery. It checked 2.65V so I still wasn't sure that was the problem. Anyway, I put in a new battery and voila, everything came back to life. Happy Day! Lesson learned! Even a somewhat weak fob battery on this bike can leave me stranded! I suppose the smart play is to keep a spare fob battery onboard.

In future be advised...
The factory fob battery may or may not last more than a year. The batteries in both my new fobs died almost exactly one year after buying my AK. I replaced the battery in one fob and it has lasted fine since Nov 2022 until now.

There IS an indicator that shows if the battery in the fob is good or not. When you press the silver button on the fob and see the LED light flash on/off then the battery is still good. If no LED light then it is a bad battery.

There is also an alternate way to start the AK if the fob battery is dead. If you look on top the panel over the right glove box you will see a symbol of concentric circles. Place the AK molded logo of the fob directly on that set of circles and press the startup button on the ignition knob and the bike will start. NOT the Kymco logo but the AK logo. This will only work if the battery is actually dead since the system is smart enough to sense a fob with any amount of battery charge left. When replacing a battery in the fob there is a foil antenna sticker on one of the shells of the fob. DO NOT LOOSE THIS. It is needed to start the AK using the fob with a dead battery.

This feature of starting the AK with dead fob is the same feature as almost any vehicle with keyless start. My Rav4 will do that also. That is why I only put the battery in one fob. The other spare fob I keep without a battery in it and I keep that one in the storage box of the AK so I don't waste a battery. I also installed an emergency seat latch release on my AK so there is no need to turn on the AK to open the seat. It is hidden so can only be used if someone knows exactly where it is. I posted how to do this on this forum a few years ago. I actually use that latch release for much more than emergencies since it is so easy to get under the seat without turning on the AK.
/bob
2024 Kawasaki Vulcan S ABS in Pearl Sand Khaki
2022 Kymco AK 550 Super Touring Extreme in Matte Deep Blue
RETIRED - US Navy and Air National Guard and civilian career

Hornblower

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Re: AK 550 weak fob battery
« Reply #3 on: September 25, 2025, 05:13:08 PM »
In future be advised...
The factory fob battery may or may not last more than a year. The batteries in both my new fobs died almost exactly one year after buying my AK. I replaced the battery in one fob and it has lasted fine since Nov 2022 until now.

There IS an indicator that shows if the battery in the fob is good or not. When you press the silver button on the fob and see the LED light flash on/off then the battery is still good. If no LED light then it is a bad battery.

There is also an alternate way to start the AK if the fob battery is dead. If you look on top the panel over the right glove box you will see a symbol of concentric circles. Place the AK molded logo of the fob directly on that set of circles and press the startup button on the ignition knob and the bike will start. NOT the Kymco logo but the AK logo. This will only work if the battery is actually dead since the system is smart enough to sense a fob with any amount of battery charge left. When replacing a battery in the fob there is a foil antenna sticker on one of the shells of the fob. DO NOT LOOSE THIS. It is needed to start the AK using the fob with a dead battery.

This feature of starting the AK with dead fob is the same feature as almost any vehicle with keyless start. My Rav4 will do that also. That is why I only put the battery in one fob. The other spare fob I keep without a battery in it and I keep that one in the storage box of the AK so I don't waste a battery. I also installed an emergency seat latch release on my AK so there is no need to turn on the AK to open the seat. It is hidden so can only be used if someone knows exactly where it is. I posted how to do this on this forum a few years ago. I actually use that latch release for much more than emergencies since it is so easy to get under the seat without turning on the AK.

Great info. Thanks, Bob!