2002 Honda Civic Heater/AC Blower Fan Failed

SMOOTHRIDE

MEMBER
2002 HONDA CIVIC
1.7L
4 CYL
2WD
MANUAL
120,000 MILES

A few months ago, I noticed that my Civic's heater/AC fan blower was suddenly intermittently inop when attempting to control it with the dashboard switch. Last week, I found that the fan would no longer turn on at all in any switch position.

Troubleshooting included removing blower fan from housing under glovebox and observing it as the ignition switch 'accessory' position was selected. Fan blades could be seen moving for a split second only to then stop. After the blower fan motor was replaced with a new part, repeating the ignition switch troubleshooting had the same results.

Next, the fan motor relay under the hood was replaced. Still no change in fan behavior. All fuses in the fuse box appeared normal. Have been also told that the symptoms described don't point to a bad resistor.

Any ideas out there?

3 Replies

HOMER1967

MECHANIC
875 POSTS

It sounds like the fan speed switch may be faulty, can you get it to run on any speed at all?

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Monday, November 17th, 2014 AT 5:12 PM

SMOOTHRIDE

MEMBER
2 POSTS

Changing fan speed position did not change the momentary behavior of the fan with the ignition switch in the 'accessory' (pre-engine start) position. This really intrigued me since it was apparent some current was briefly getting to the fan motor.

I had a Chilton's manual and looked at the electrical wiring diagram and noted that a solid state transistor was also present. NAPA Auto and O'Reilly's said it was a 'resistor' and that this probably wasn't the cause based on my symptoms. Honda parts department said that it likely *could* be the problem, so I bought the part at O'Reilly's for about $48 (Honda wanted over $80. Yikes!).

Once I swapped out the blower fan transistor/resistor (easy.2 screws) mounted next to fan motor under dash, I turned on the ignition to the 'accessory' position and noted first that the fan impeller did NOT move! When I turned on the fan speed selector knob, sure enough. The fan functioned flawlessly!

Problem solved! Thanks Homer1967 for your kind reply.