I recently installed a new Thermostat, sensor and changed my coolant. Everything went great. I was able to enter the service menu with the key by pressing 3 times on the reset button, etc and it showed my engine was a little low on oil.

long story short my oil sensor wasn't accurate and I ended up topping the oil up too much so figured time for an oil change anyway.

i did a complete oil change first with a Liqui Moly flush and filled with new With Mobile 1 European synthetic 0w40 (8.5Q)

Anyway after doing the oil change the service menu doesn't work, like it doesn't exist? I didn't spill any oil. There's also no option to check the oil level reading without the service menu like I once could.Car sounds and is running fine.

should I maybe disconnect & reconnect the battery? Has anyone ever had their service menu just disappear?

any advice or opinions appreciated.

I disconnected the negative terminal of the battery and upon reconnecting the service menu is back. It shows the oil quarts as quite low. When I try checking the oil level the non-service menu way it says checking followed by "observe waiting period" seemingly indefinitely.

after letting it sit for about 5 minutes with the engine off the observe waiting period goes away for me and being on uneven surfaces messes with the sensor and it won’t read correct