1980 280TE Euro... blower fan died.... a slow, motor-bearing demise...
replaced fan... fan works only when ignition is on and the engine is not running...
Once engine fires up, fan goes away.

Thought it was a damaged switch due to overload caused by previous fan failure... but then again, my limited experience has opened me to the possibility it might be more complex... perhaps tied in with air conditioning somehow.

before I buy a new switch, wanted to check with somebody who might know here...

searched previous threads, but to no avail. insights would be mucho appreciated.

__________________
Wil B
1980 TE
1983 TE
1884 TD
1971 450SEL
1959 220S

so, I bought a new fan switch at the dealer, and was able to corner a clearly knowledgable tech... he said, wrong switch. ignition switch is probably the problem, which, when you think about it, makes sense.
very common on the 124s, not so common on the 123s but it still happens.

so now i am hopeful. will research a new ignition switch and keep my fingers crossed.

hope this helps someone else... weird posting a reply to myself, but a lot have threads have been helpful to me on this forum, hope this might be helpful to someone in the future.

as the saga continues, will post. hopefully, will solve.

__________________
Wil B
1980 TE
1983 TE
1884 TD
1971 450SEL
1959 220S