Two things, the connection between the new unit and the wire harness has to be a 100% good solder connection to carry the load. The other thing is the ground. There should be a ground connection near the headlight where a wire bolts to the inner part of the sheet metal. Make sure that is clean and tight.
1981 280GE SWB
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
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