I’m having some strange behaviour with my SRAM Red rear derailleur.
I noticed the RD had a constant blue light showing. Google says that might be water, do I to the battery if and left it in a warm spot, which seemed to solve that.
I went in a ride a few weeks after and noticed the shifting was not moving into easier gears. It would shift in the smallest 5 cogs, but just not want to go to bigger cogs. After a short time this resolved itself.
I was messing with gears after this and noticed that it happened again. The rd just would not move. It would make the coding noise as if it is trying to move, but was not going anything. I tried leaving the battery on charge overnight, and in the morning all was fine.
I went for a ride and about 3 hours in my head unit started beeping every time I shifted. Looking in the settings, it would disconnect after each shift was fine, and so reconnect on the next shift.
I went to the lbs and they could not connect to the rd using their app. I tried and could not connect with my saved ads settings.
I changed the battery fully again, and then the app would connect.
So, possible the mech is water damaged and randomly working, or the battery is somehow messing with the electronics. I might try a new battery first before a whole new rd, but thought I’d ask if anyone had seen similar weird behaviour?
When electronics behave oddly it is very often the power supply (in this case the battery). My recommendation would be to borrow a battery from a buddy or asking you lbs to try a different battery (sram batteries are not cheap).
If the new battery fixes the problem, just buy a new battery.
If that doesn’t fix the problem, try contacting sram next. They can probably provide guidance on the meaning of the blue light and if it’s something that can be fixed without replacing the rear derailleur that’s great because rear derailleurs for electronic drive trains are not cheap.
SRAM AXS is generally very reliable in my 5 years of ownership experience. If you have a front derailleur swap out the battery from the front to the rear and see if any change. Give the contacts on the battery and derailleur a good clean with something like isopropyl alcohol, or even just a good wipe down. If you haven’t done a firmware update it might be worth a try, it’s very easy to do via the SRAM app, worth doing every now and then. If you have the SRAM AXS app it might be worth seeing if it picks up any issue with the battery. Hopefully you can fix it, as it is an intermittent problem and they are always a pain because it’s hard to do a warranty claim unless it’s a total failure often!
I’d still try to warranty it via SRAM. You can find their local service number in your country. They are typically very good at standing behind their stuff even if it’s out of the stated warranty period. You’ll also need the serial number of the part. They publish a guide for where on the part you can find the serial too.