I have a '93 300E 3.2L and have two working auxiliary fans. They work fine in the "low" mode, but they sporadically turn on and off when they are in "high" mode, and of course, they cause the relay to click on and off up in the fuse box.
What causes the fans to switch to high mode? Whatever that is has the problem. Is it the Radiator Fan Controller/Resistor; For Auxiliary Fan?

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