I have an 89 300CE and my a/c heater blower doesn't work. WHen I looked at it, the fuse housing had arced and the wiring was cooked. I mended the wire and replaced the fuse, but no air! I checked the voltage but couldn't get a reading. What's next???

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89 300CE
91 Supercharged Miata
99 E320 Wagon

If you don't have 12V at the fuse then the electrical portion of the ignition switch is bad!

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MERCEDES Benz Master Guild Technician (6 TIMES)
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Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Thanks for replying, MBDOC. I am not familiar with the electrical schematics, but from what you're saying, it's the ignition switch that isn't working? You may be on to something, because before the motor went bad, I had a problem with the ignition switch... I had to turn the switch counterclockwise fractionally to get the motor to work. Is this it? Is your recommendation to change the ignition switch, and is this something a DIYer like me can do?

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89 300CE
91 Supercharged Miata
99 E320 Wagon

The switch takes about 1.5 hrs at dealer to replace. Removal of underdash panel & laying on your back is necessary.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator