W124 Mysterious Electrical Issues

[Midnightlsc]

As I 'm driving at times multiple items lose electrical power. For example, the radio turns off, windows & sunroof stop working, heated seats turn off and power seats do not work, sometimes power antenna lowers and raises and finally SRS light comes on for a few seconds. At other times everything works fine and then all items no longer work again. There is no consistent pattern except that perhaps movement and not time changes the situation. It is quite a nuisance when you park and can no longer roll up the windows or while driving the radio shuts off. The car is a 1995 E420 with 57,000 miles. I have changed the combination relay as I had erratic wiper movement and that is now resolved. Could the convenience relay be the culprit for some of the issues?

Also as of late the low beams do not go on, but high beams and fog lamps are fine. But these permanently stay off, not intermittent like the other problems.

Thanks ahead for any advice.

1995 E420 Fast!
1998 C280 Everything works!