Haraisuru

My '03 Civic's blower stopped working a few months back and now with the weather turnig I had to pay it some attention.

Started with the easy and cheap fix and checked all the fuses under the hood and driver side but no joy find a fix.

Turned to the next culprits on my list the blower motor and its resistor (appears to be called a transistor on some places).

At first observed the motor kick when power is applied by the key on position but it immediately stops so we pulled it and verified the motor work (on all speed settings) by hooking it up in another civic, and moved onto the resistor. We got no readings across the resistor initially so thought we had found the problem. Bought a new aftermarket resistor and threw it in but to our surprise there was still no air blowing from the vents.

Feeling rich, impatient or just stupid sitting in front of the parts store bought new relays with no luck and now a lighter wallet.

Frustraited again we returned to the house and started searching the web. After some reading we check the voltage at the blower relay connections and got 12 volts. Moved on to resistor and got 12 volts and the connector to the the blower motor also showed 12 volts with the key in the on position.

So at this point were are totally at a loss. We know the motor, resistor, fuses, and relays are all good, which seems only to leave the wiring itself or possible the control panel on the dash.

Realizing there is power at the blower motor connector it is hard to believe it is a problem with a wiring short or the switch but not sure how to proceed with narrowing it down.

Maybe worthy of noting is that regardless of the control **** setting the power at the blower motor connection is always 12 volts. I would think this voltage would change as the control setting changed the resistance in the resistor for the fan speed but I could be wrong here as I am a total noob.

We did attempt to go throughout the DTC 12 steps found at: https://honda-tech.com/forums/showpo...9&postcount=10 but ran into several problems and weren't sure if we found problems in the continuity or was just not doing it correctly...

Any advice would be much appreciated and thanks in advance.

Haraisuru

Got everything working again! This was a case of a rush to judgement and bad luck. I tested everything but the control panel and then began searching firums again where a case very similar to mine ended up with the resistor being bad. So I put in my old resistor and did a defective return on the new resisitor.

I got home and decided I would start the guide linked above over from re beginning and got about half way through it to the point of testing the resistor. As I was checking the resistor I turned the key to the on position with the blower switched on, and to my surprises it worked.

Everything is my original parts except the blower relay so my best guess is that the original issue was a bad relay. The simpleton that I am I verified the motor was good and replaced a perfectly good resistor with a bad one that was DOA out of the box. Since everything was still not working with a bad relay and now bad resistor, I then continued by checking everything else including replacing then originally bad relay which I replaced leaving only with the new bad resistor. SO then when I put my original resistor in to do a defective return on the new resistor just because nothing was working, I lucked out with everything working.

Could have been worse but I guess I deserve what I got since I tried cutting corners...

Just glad that it works now.