Hello All,

First time user. I have a 2005 Honda Accord Sedan and I turned on my heater to warm up and in the morning it worked just fine. Did it in the afternoon and nothing. The lights come on, but no air blows out on A/C or Heat, not even defroster. I don't even know where to start to look. Can someone please point me in the right direction to start?

 

First welcome to HAF.

Next, do you have a testlight or voltmeter to do some testing?

My guess, replace nothing on a guess, is that the transitor/resistor for the blower motor has given out.

One thing you can do without tools, need a few feet of wire. If you remove the plug from the blower and use two pieces of wire from the battery to the blower motor....does it spin? You are "hot wiring" the blower by giving it direct power and ground.

 

A common problem on many Hondas is the blower power transistor. But, answer some of the following questions before replacement of anything.

Here is a thread regarding where the blower power transistor is located and repair/replacement.
https://www.hondaaccordforum.com/for...-repair-40796/

A. What trim level is your Accord (e.g., DX, LX, EX, EX-L) and 4 or 6 cylinders?
B. Does the blower work on HIGH? The blower power transistor controls the blower motor in all speeds except HIGH. If it works on HIGH; but, not on the other speeds, it usually will be the blower power transistor.
C. If it doesn’t work on HIGH either, try this simple test. Essentially, you’re going to ground the Blue/Black wire on the electrical connector for the blower power transistor. With the Blue/Black wire grounded and the ignition turned ON, the blower should run. If the blower motor runs with this test, then the problem can be the blower motor transistor or a wiring or a connection problem.

1. Locate the blower power transistor under the passenger dash.
2. Unplug the electrical connector to the transistor unit.
3. Attach one end of a piece of wire to the cavity (where the Blue/Black wire is on the connector). With the connector plugged back in, touch/attach the other end of the wire to a ground source (the other end of the piece of wire touching exposed metal on the car (like a metal bracket). Turn the ignition ON, does the blower motor now run?

• Blue/Blk wire is a wire with blue color insulation and a black stripe.
• The piece of wire (speaker wire works) can be relatively short, you only need enough to reach from the blower transistor power connector plug to touch a metal bracket or exposed metal for a ground source under the dash.

 

I was just looking at the circuit diagram again and thought of this even easier test than the one I previously mentioned. If it doesn't run this way, then you can perform the test I previously wrote to check that the Black ground wire/connection is good.

1. Locate the blower power transistor under the passenger dash.
2. Unplug the electrical connector to the transistor unit.
3. Attach a jumper wire (short piece of wire) from the Blue/Black wire cavity to the Black wire cavity on the unplugged electrical connector. Leave the connector unplugged.
4. Turn the ignition ON, does the motor run?

 

Thank you all so much for your help!! I didn't think that could do it!! But I did. It was a connection problem! Easily fixed! I didnt waste hundreds of dollars!! Thank you all so much!!!

 

Thanks for reporting the issue was resolved easily.

 

Can you please tell me where the bad connection was.
Thanks
Mike Williams