1990 740GL "Service" light.

[MasterBlaster]

It's the one that reminds you to change the oil, *not* Check Engine.
How do I make it turn off? (Besides waiting 2 minutes)

I pulled out the rubber plug on the face of the instrument panel.
I got a skinny pen refill so I could poke the button inside.
I've tried:
- Single poke with the engine running.
- Single poke with the key on, engine not running.
- Single poke with key off.
- Holding the button for 20 seconds, engine running.
- Holding the button for 20 seconds, engine not running.
- Holding the button for 20 seconds, key off.
- Holding the button while turning key to "on".
- Holding the button while passing through "on" and starting engine.
- Poking button 5,327 times with engine running, while cursing loudly.
I'm out of ideas.