BMW Repair: 1998 BMW 328i, coolant level, replacement button

Question
I see your expertise is with 1999 and newer, but I thought I would ask questions anyway as I saw answers for older models as well.  So here it is:  I just acquired a 98 BMW with 160K miles.  It use to be mine but I gave it away for a few years.  Since getting it back it has an array of little quirks and issues.  I will list them in the order of importance for me.
1) The driver seat will not go forward or backward.  The motor for moving the seat up and down work.  Is there a quick fix for this or do I have to take the seat out?
2) On the warning lamps, the airbag light is always on?
3) The check control seems to work, but the outside temp as well as clock and time do not work?  (outside temp reads -35 degrees), the clock and date do not illuminate at all.)
4)In the glove compartment, the button for the trunk is gone? Is there a replacement button?
5)Sometimes the check coolant check control comes on, but if you add a little coolant all is ok.  However, the coolant level looks fine.
6)The instrument panel is very dim. How do you replace the led?
7)When it is cold outside, less than 40 degrees, the check engine light comes on.  When it is warm outside, it does not?

I guess is there a good book that I can buy to help me fix these little issues.  It is an old car in decent shape that I do not want to sink a lot of money into, but would like to continue to drive.  Female and all I am a little mechanically inclined, so I think I can tackle most of this.  Definitely don't want to do anything with the engine.

Thanks!
Sandy

Answer
Sandy, BMW's are expensive to fix plain and simple. I would remove the mounting bolts for the seat and lean it back and opperate the button and see what is or isn't going on. You need to have the airbag faults read out to see what fault is stored. Outside temp sensor needs to be checked in is in the bumper corner area. I would imagine the button for the trunk mounting has broken and the button has fallen back. You should be able to get these parts through your dealer. Coolant level sensors are a common problem with your model. If it is questionable replace it (bottom of expansion tank). Instrument cluster has to be removed to replace the back lighting bulbs. You need the faults read out of the engine computer to see what faults are stored for your temperature issue.
-Evan