THF40

Its bloody cold where i live and i need my heat!!!

So, my fan suddenly stopped working after ~15 min drive. I have hot air rising from the vents.

No matter where i turn on the fan dial, the fan doesn't wanna turn on.

Here are the troubleshooting I've done so far,

I checked the anti-freeze level, its good.
I checked for broken fuses and replaced with spares.
I took out my fan and attached it to a 9 volt battery, it works. I don't know what else it can be.

Please help.

Redneck_cdn

on most cars there is a resistor pack in the duct-work just outside the fan/blower motor, not sure on the hondas but take a look under the passenger side kick panel for some large gauge wire plugging into a removable resistor pack. Normally if this goes you would have high fan only as the resistor pack is used to drop the current down for the slower speeds and needs to be in the air stream to keep cool.


FYI,,
http://www.rockauto.com/catalog/more...051&cc=1425451

Check the Blower fan relay?

Have you cleaned/replaced the cabin air filters as if they are clogged it could reduce the cooling on the resistor pack causing pre-mature failure.

THF40

So if the resistor pack goes, i should still have my fan running on high but I have no fan at all. The fan doesn't even come on when i crank it all the way up.

I have checked the blower motor relay, it is fine.

I have not checked the cabin air filters. I will do that shortly & clean them out.

Any other suggestions?

ezone

Blower power transistor is what failed.

It does not act the same as the old type blower resistor, you will not have any speeds at all when it fails.



Locate the power transistor unit, jumper the 2 fat wires and the motor should run full blast.
Google for ideas on hacking it. I made a test unit that way to speed diagnosis.
It should be replaced though.

Redneck_cdn

By the look of the image in the link and the attached head sink, it may be a MOSFET (aka) electronic variable load pack and if it fails you may get no output... no fan at all.


Ezone da Man.....

Inspect/replace the cabin air filters while you are at it.

ezone

The usual failure is the thermal fuse inside the power transistor unit.

Could be from high amp load like a failing fan motor, overheating from poor airflow like clogged filters, or just plain went bad.

CraigW

iTrader: (1)

For 01-05 an easy test is set fan to on, remove cabin filter then peer in at fan cage as you turn key to II.... if it turns a tiny bit, then stops the TCO is open.

THF40

how do i set the fan to on?

ezone

Use that **** on the dash.

THF40

Oh...Hahaha! Okay I will try that!

I also tested the power transistor. It does not fall into the range of 1.4-1.5k ohms. My multimeter shows values between 1.7k & 1.8k. Does that mean my power transistor is bad?

CraigW

iTrader: (1)

That may be within tolerance.

Did you try either of the 2 test ??