hi on my 1980 450sl i replaced the servo with a used working unit and a used climate control . first turned it on but only defroster blew air and the thmb wheel only stayed hot in ether positions. i replaced the amp speed control unit under the glove box . turned it on and the temp changed also the hi lo and by worked. the only thing the blower when in hi mode was not like in def mode
the system worked for 10 min then only defrost. , took out the amp box and opened it to see the transistor was toasted . what could cause this to happen,could the parts be that fiff, my old servo said 102 the replacement said 104 inside is the same
any help please also the door locks dont operate vaccume issue , the air dosent blow out center just top and bottom