A/C condenser fan not switching on

[gregp1962]

1984 300CD US.
I notice that the fan isn't switching on even when it is very hot. It does seem to affect the function of the AC system. It isn't getting cold in city traffic in hot weather. It does ok on the freeway. I tried jumping the temp switch. That didn't do anything. This fan was replaced just a few years ago. The fan shouldn't be bad. Any other ideas?

[Diseasel300]

Fuse? Relay? Pull the plug to the fan and check for voltage?

[ROLLGUY]

Check the link in my signature. You need the fan relay. It powers the fan from a separate fuse whenever the compressor clutch is engaged.

[sixto]

I thought the aux fan was triggered by a refrigerant temp switch on the dryer.

Sixto
98 E320s sedan and wagon
02 C320 wagon

[engatwork]

I think it is sixto. To the OP get ahold of Rollguy. He has a kit you can install that will make the electric fan run anytime the compressor is engaged.

[tangofox007]

Originally Posted by sixto

I thought the aux fan was triggered by a refrigerant temp switch on the dryer.

It is. But the OP states that he jumpered the temp switch and the fan still did not operate.

[tangofox007]

Originally Posted by gregp1962

This fan was replaced just a few years ago. The fan shouldn't be bad. Any other ideas?

Here is an idea: power the fan directly and find out for sure if it works or not.

[sixto]

Originally Posted by engatwork

I think it is sixto. To the OP get ahold of Rollguy. He has a kit you can install that will make the electric fan run anytime the compressor is engaged.

I misread ROLLGUY’s post.

Sixto
98 E320s sedan and wagon
02 C320