jonnyb

Hi all, first post.

My front heater hasn't worked for a couple years and, after moving from the relatively temperate Portland, OR, to Colorado, the winter has been brutal. I am limited on funds so want to repair this as cheaply as possible. Here is what is going on:

*Small amount of heating coming from vents, but no air
*The colder it gets, the less heat--the defroster works minimally on warmer days, but barely at all now (at least so far as I can tell)
*Back heater works
*I checked the fuse behind the glove compartment and it wasn't blown, but there was some white corrosion on it

What am I looking at here?

Thanks!

jonnyb

While I'm at it, here's another one: especially when it is cold, the truck often revs up to about 2 on the RPM dial on idle--when stopped at lights, etc. Is this a simple matter of a low fluid? I'm long overdue for an oil change and have had a pretty bad oil leak that I think requires some repair (I've been putting a couple quarts in every 2-3 months).

keithguts

well if I was you, I would change the fuse if it had corrosion on it. It would be a cheap way to start. There might be more fuses as well, but not sure.

What year is the rig and type?

Also, welcome to yotatech.

jonnyb

Thanks for the welcome and quick response, Keith. It is a 1991 4Runner, 4-cylinder engine. Not sure model number.

Yeah, I will probably start with the fuses--but I put this off so long that we've been getting snow the last weak and it has been pretty cold! Luckily I just discovered that the back heater actually works, so this heats the cabin up a bit--and mollifies my wife somewhat! .

keithguts

Well it seems to me that the heater works, but the fan is out. Could just be a wire off of something. But as you said, it would be a good idear to change the fuse. Also if you have the book on the rig, it might tell you of other fuses that may control the heater fan as well. I have a 1995 runner. If you don't have the book with the rig, I will check mine out for you as it might be the same, but not to sure of this. I had this problem in a ford truck awile back, and one day it was really cold and I was freezing and pissed at the same time, so I gave the dashboard a good slap, and the dam thig came on. Every time it went out on me I would hit it.

jonnyb

Funny--although I don't think that will work.

I don't have the book, just the little manual, which is pretty useless. Although it seems that there is only that one fuse, as far as I can tell. I will swap it out for one of the spares from under the hood and see what happens.

jonnyb

OK, replaced the fuse and nothing. What are the options at this point, and would be the next diagnostic?

I'm assuming there are three options: 1) a wire (good, but hard to diagnose?), 2) a part of the blower motor like the fan (not good, but do-able), or 3) the entire blower (bad).

keithguts

Could be any one of the options. I'm sure others will tune in on this tho. Keep a look out for more info. Sorry I can not be of more help.

You can also go into the search any type HEATER, HEATER FAN, etc and see what comes up. Good luck. Keep us informed of your findings.

TRY THIS: https://www.yotatech.com/forums/f131...ght=heater+fan

jonnyb

That link is intriguing--the only problem is locating the heater fan relay without a manual. Any links to pictures that you know of?

Thanks for the assistance, btw.

keithguts

It should be right behind the glove box. That is what it says in trhe link I sent to you.

jonnyb

OK, i found it--now the tricky part is getting the housing off as on first try it was a no go. I'll play with and see what i can come up with.

keithguts

Cool. keep us informed.................

jonnyb

Didn't work. I got the relays undone (there were two of them)--one was corroded, one wasn't. I scraped until the corroded one was pretty clean and hooked it back up. Nothing.

Unless there are some other ideas, I'm probably going to have to take it to the shop