To all the experts,

I am working on a 1992 300E with a heater blower problem. The controls are fine, the blower it self is fine, the regulator underneath is fine. What I found out was from the blower connector (3 wires), the red wire is not giving any juice at the connector referred to in (1) below. If I jumped the line directly from the battery, everything seemed in order. It could be anything, but does anybody know:

1. If the black male three-pronged connector (bolted down to the firewall) is some kind of resistor device? How do you remove it for checking? Does it require getting inside the dashboard?

2. Does the blower utilize any relay? If yes, where is it located? If inside the relay box next to the main fuse box, which one is it?

3. Any hint as to why this outtage is very much appreciated.

Thank you.