Have a 97 C280. A couple of weeks ago, we noticed that the door locks could not be locked with the switch on the dash. The doors can be locked with the remote key. Also, the dome light stays on all the time unless put into the off position (position 3).

The other day, the trunk opened all by itself when parked and sitting. So we closed the trunk, but we could not reopen it; not with the remote double-click, the key, or the interior trunk switch.

With the car off, sitting in the car with the doors closed, I press the door lock interior switch and I hear something run, but the locks don't lock. Still sitting in the car, I press the remote key and the same thing runs, and the doors lock or unlock as I need.

So then I figure something must be out of kilter with the computer, and after trying a few things, like locking the doors and unlocking the doors with the remote, and pressing the interior switch corresponding to the remote action, I now have the trunk unloking and locking as it should, but the door locks still only work with the remote and the interior light stays on unless turned off manually.

So, what do you think could be causing this?

Thanks
Fred