I've seen some posts around on several FB pages, as well as the other 390 page on reddit about the no turn signal issue. It involves a complete lack of turn signals, as well as a yellow warning message on the TFT.
As of now it seems KTM doesn't have a fix, but that may change as time goes on.
I wanted to share my findings, and give some insight as to how I fixed mine.
My bike is a 26 model.
I didn't try a new battery, and didn't check grounding points. I did check continuity at the signals, and ground was fine. I did also loosen and then retighten the battery terminal connections, with no change.
I believe the issue has something to do with the wattage rating of the stock signals. I think they draw too much power for the relays, or perhaps something to do with the ECU or TFT itself.
Unplugging the fronts allowed the rears to work, and vice versa.
I ended up buying some mini LEDs and installing them on the rear when I did my tail tidy.
I now have 4 working signals, but the error message still displays intermittently.
I have notified KTM, but they just referred me to my dealer. I will have them investigate further when I go in for my first service, but figured I would put this up for any one who doesn't want to wait for KTM or a dealer to figure it out.
The signals I installed are 1w each.
These are the signals I ordered. They are tiny and cheap, but bright and well built. https://www.ebay.com/itm/397466445435
I cut the wires off the stock signals and used some connectors I had on hand, but you could use these adapters instead. https://www.urbanobruni.it/en/lights/turn-lights-adapters-and-connectors/plug-play-adapters-and-connectors-for-ktm/single-pin-connectors-for-led-turn-signals-for-ktm-from-2024/
You could use these on the fronts as well, but they actually already have pigtails coming from the main harness. The main harness connectors look like these https://www.ebay.com/itm/335043961105?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1OaUzMMEQT3uG_mDrYgamtA48&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=335043961105&targetid=2446939459199&device=m&mktype=pla&googleloc=9057182&poi=&campaignid=23193939981&mkgroupid=188302949672&rlsatarget=pla-2446939459199&abcId=10495177&merchantid=5304468625&gad_source=1&gad_campaignid=23193939981&gbraid=0AAAAAD_QDh8VAQ82aTwtVpEJRCz9JtlYx&gclid=Cj0KCQiA-YvMBhDtARIsAHZuUzKcrnMzHdwez2M0I-KfI85SZXBjCFYdK7X1Nt_7CDhQen_EYB3yY7YaAobtEALw_wcB