Here's a tricky one:

My climate control fan has been gimpy: every other time I started the car, it wouldn't work. Once it started working after having driven for a 1/2 hour or so.

So I figured it was the fan relay in the fuse box. Ordered and installed a new relay (Part Number:MT1240). Didn't fix the prob right away, but wife reported that when I shut the hood, the fan kicked into life. https://www.hondacivicforum.com/foru...s/confused.gif

So we drove around, turned the car off, and then started again: NO FAN. So I said what the Hell, and opened and slammed the hood (not too hard--I love this car) and the fan KICKED ON AGAIN!

Thoughts?

 

Could also be the fan motor or the power transistor. Measure voltage at the fan motor with the fan still plugged in, the key on, switch on high, and while the problem is there (the fan not running.) Measure voltage between the two wires.

12 volts between the two wires: motor is bad.

If you have zero volts between the two wires, measure from each wire to ground.

12 volts on both wires: almost certainly a bad power transistor. This part fails a lot. The power transistor is mounted in the ductwork near the fan, you need to remove the glove box for access. Some parts stores call it a resistor even though it is not.

Zero volts on both wires: Lack of power from under the hood (fuse, relay, fuse box, other connections).

 

Thanks mk378! Rolling up my sleeves. . .