I have a 1974 240D. My question is about the passenger inner fender wall. Theres a fuse box with 3 wires brown, red& black that go to a female plug near alternator. What is this for & where does it plug into. Thanks

 

Is there actually Fuses there or is it a Termnial Block?

On the Later Models there is a Test Connector. I assume used at the Factory when the Car was built. I so far have not read of anyone using that connector for anything.