I have a '96 E320 which has recently developed a problem with the A/C fan. The A/C cools good but the fan will not speed up. Regardless of the fan speed indicator in the dash, the volume of air feels like the fan is on low.

An aquaintance suggested that the blower might have a relay or resistor that was bad. Is this something that I can check myself before taking to a shop?

I do not mind taking to a shop but I like to be as informed as possible before I go.

Any advice would be appreciated.

Thanks,
John Hamilton

If you have a multi-meter, test the voltage that's being sent out from the controller. If it changes, and you fan speed doesn't change, it "might" be the fan problem.

If the voltage keep coming out the same, it's "probably" the controller problem.

If case the picture came out fuzzy, the green box read "Electronic Blower Control, Rear Of Engine Compactment"

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That is a great diagram, HOWEVER the electronic blower regulator is mounted to the blower motor INSIDE the car. The passenger side underdash panel must be removed to access the blower motor & regulator on the W210 chassis.

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