107 heater problems
 

having heater problems 82 380sl.
tested blower with 12 volts ,at outside terminal blower works all stages.
replaced climate control unit & heater regulator.
only get blower working if i wiggle the harness on the left side of the unit. opened harnesses and all solder joints looked ok.
when working do get heat so i think temp regulator is ok
do the wire harness deteriate and short out.
should i replace wire harnesses for heater units where do you get them?
is there a part missing that controls the blower motor that i am missing and don't know about. there does not seem to be any on the schematic