So, I changed the thermostat in my car today (07 E60 525xi), and was curious to check the engine/coolant temperature after the job had been completed. As I went into the hidden menu the first time, I guess I incorrectly entered the unlock code into the menu at item 19 (screen where you see Lock: ON).

I didn't think much of it, but then I went in to try and re-unlock it, and if my engine is on, and I hold the trip reset button, I just see the warning triangle for a few seconds, then it goes back to my temp/date time. If I try to access the menu when the car is ignition on but engine off, I see just a yellow Exclamation point (!), and cannot see any information in the top window of my dash. I think I've locked myself out of even being able to try and unlock the thing!

Anyone ever experience this, and know how to overcome? Searching on the boards and google have revealed no results yet... Thanks in advance!

Hold the button in longer.

The red warning triangle appears, then goes back to normal, then about ten more seconds of holding the button brings up the hidden menu.

+1

The symbols you described are perfectly normal. If holding the reset button longer doesn't bring you to the '01' display eventually, then something's wrong.

Good luck

Thanks! Went back in this morning and was able to get to the instrument hidden menu when the car was started (engine on). When the car is in Igintion ON and engine OFF, though, I am still seeing just an Exclamation point. If i hold the trip reset button, it begins to ask me if I want to reset certain service intervals, and then I can see myself paging through the services (can tell by the mileage listed in the lower window which service it is), but the top, instead of having an image of the service icon, still has the exclamation point. Any ideas on this?

you need to hold it for about 10 seconds before letting go.

I've held it in for about 20-30 seconds... I keep seeing the Exclamation point (!), its yellow. It also asks me if I want to reset, which is referring to the service interval that it is on. The issue is, I can't see which service interval it's on because the top screen (where he hidden menu lives) is permanently displaying this yellow exclamation point...

take a video and post.... it's hard to judge this otherwise