Jumbo Jet

We have an 04 TSX with around 80k miles and last week the fan just quit blowing. The readout on the display is working, but nothing blows, even heat or highest fan settings. Checked the fuses under the hood and they are ok. Unplugged the blower motor and I'm getting power to it. Read a ton of posts about the transistor problem so went to Honda and bought a new transistor. Plugged in the new transistor and everything worked perfectly. Then my wife calls me the next day and said the blower quit working again. Worked great for a day then back to square one.

I tested the old and new transistors with the DMM and I'm getting 1500 ohms on both of them. I thought the transistor that Honda gave me might be a dud, so I tried to swap it for another one. They gave me a hard time because its an electrical component, but one of the techs told me that if I'm blowing transistors...I have a bad blower motor that is over loading the transistor.

I'm not sure what it could be a this point. When the new transistor was put in, everything worked, so I'm ruling out the compressor or blower, but I could be wrong. Cabin filter is brand new as well.

Any advice is greatly appreciated.

Thanks in advance

TexasHonda

since you're getting power to the blower, most likely explanation is faulty blower motor (worn brushes). This will cause intermittent operation as the brushes make contact, motor runs for a while, then on shutdown refuses to start again.

Sometimes you can confirm worn brushes by firmly thumping the blower case w/ your hand. If motor comes on and runs w/ this action, worn brushes is confirmed. New motor is required as brushes are not replaceable.

good luck

Jumbo Jet

Thanks for the response TH, its very much appreciated. Ok,I took your advice and went out and beat the hell out of it, we'll actually just tapped the hell out of it, and still nothing. However, when I plugged in the new transistor again, the compressor kicked on for about 3 seconds, then shut off. But the fan never came on in those 3 seconds. It is sounding more and more like the blower motor..huh?

Thanks again for your help.

TexasHonda

If you have 12V to the blower motor and no movement, motor is kaput.

good luck

Jumbo Jet

Ok.. Back to the drawing board. Replaced the motor with a new one and still nothing. I'm going to try and return the transistor I bought from Honda dealer tomorrow and see if they'll exchange it. The dealer had told me a bad motor will blow the transistor, so I'm wondering if that's why it's not working with the new motor in.

Any other ideas?

Thanks again.

TexasHonda

Try removing the transistor module and installing a jumper across contacts 2-4 or simply supply a ground wire to contact 4 (blu/blk wire). Blower should run wide open w/ keyswitch On. If it does not the blower is bad or wiring problem to blower, fuse 30 open, or ignition switch fault.

If blower is good and system won't work w/ transistor modulating AC, there could be a problem w/ audio/hvac panel which supplies input to bias the transistor and control the blower.

good luck

Jumbo Jet

Ok. Quick update, but first a big thank you for all your helpful advice. It was like pulling teeth, but after 30 minutes of discussion, I somehow convinced the dealer to swap out the transistor for a new one. Then we ordered a new blower motor off of eBay, installed that and plugged in the new transistor and its been working for the past three days. Also changed out the cabin filter and its blowing great. It's lasted two days longer than the last time, so that's good. I'll update if it conks out again, but again, thank you so much for your help and advice... very much appreciated.