Issue with interior air (heat/cold) fan. Any ideas?

Well go figure. The air had been out for 5-days, and I had one more trip to the mountains to take care of this weekend. Finally, I was hoping it would just stay off this time so I could dial in on the exact problem.

What do you know... it came back on at 7500' again, on my way back home. I'm so confused.

 

This weekend is going to be the one... I'll get a baseline this weekend, and whenever it goes out again, I'll be ready for it.

Hopefully I can find these components!

 

you have gremlins in your glove box.

 

How big are gremlins?... I've searched everywhere and not yet found them!

 

this is interesting. makes me want to take my tacoma up to the mountains just to see whats up. have you talked to the dealership about this issue?

 

Nope, figured that I'd ask around here and give it "the ol' college try" before crawling on my hands and knees to the dealership.

I doubt that you'll have an issue... seems as though I'm the only lucky one.

 

they are believed to vary in size. You probably have the midget gremlins in there. They are able to navigate through your dash too...they can get pretty destructive up in that shit..

 

Fuckin Gremlins! I did'nt even think of those! I hate those rat bastards!

 

Sorry for the lack of update. The thing started working again before I got a chance to dig into it.

Thankfully (ha ha....) it just cut out on me again this weekend, which is a PITA since it's below freezing outside. I have some time tomorrow night to get under there... hopefully I can find the components and determine the culprit.

Side Note: The Blower Motor testing says to use a 5V power source @ 30A... any ideas for what I could use to get those #s? I don't have a adjustable power supply.

 

Think I might could have found it!

I'm a mechanical engineer, so this electrical crap is a bunch o hokus pokus to me. I tried to get resistance measurements, and every measurement that I took was incorrect, based on the info provided on the first page. I swapped the heater relay with the DIM relay, and no change. I removed the resistor pack, and all looks good... no burn marks... jiggled the wires to no avail.

I then pulled the heater motor out and made sure it was spinning without resistance... all good. then, I pulled the connector from the motor and took voltage readings with the fan switch OFF: 0V, and with it on: 12V.

Looks like the motor is getting power, just failing to engage. I'll try find a part and let you know how it pans out!

 

Ah... I see now that there is a TSB for the fan motor. I picked up a new-style blower motor on toyotapartszone.com for ~$120shipped, and I'll install it as soon as it gets in.

I still can't figure out how the elevation change played into this, but it happened too frequently to be a coincidence.