I had some problems/questions a while back, some without response, perhaps because they were just plain silly? Remember, I did not have a manual at the time.
As mentioned, @ the time, I did not have an owners manual, but I bought one from one of out members here a couple of weeks ago and today I took the time to read it over and learn more about my 1985 380SE.
I had mentioned something before about thinking these cars are supposed to start out in 2nd gear. Mine was starting out in 1st and I was thinking something was wrong. Well, according to the manual, all is normal, because the 380SE is supposed to start out in 1st, whereas the 500SEL and 500SEC for 1985 are supposed to start out in 2nd. I have no idea why however. I am assuming it is where the 500SEL/SEC is more powerful and 1st is really not needed?
I also learned how to set the clock on the original Becker radio. It was not correct and I am assuming that the PO did not know how to set it, considering that he had no manual either.
It also dawned on me why my "brake" warning lamp is illuminated. When the PO bought the car, he said that the light was always on, but went out when you pulled up on the E-Brake pedal - which it does, but when you let it go, the light illuminates again. Yesterday, I removed the rear tires to discover that the rear pads are virtually worn down to nothing.

I did not have the rear pads, as I thought it was the fronts that were worn, so I put the tire back on. It dawned on me today that I bet it is where the pads are so worn, that it is allowing the e-brake pedal to move down too far, thus illuminating the brake warning. My "anti-lock" also activates when I first go down our driveway, then the "anti-lock" lamp stays illuminated, so I am hoping that new pads will fix this too.
I still have a lot of reading in those manuals to do. I have learned alot about recommended oil grades, capacities, etc.
I should have read it a long time ago.