Davebarbier

It's cold in CT and I now have no heat...

I was going for a drive in the snow with my '94 Pickup 4WD. I slid the heat slider to the cold side for some reason and felt something weird in the slider. The air turned cold obviously but when I slid it back to the hot range the heat didn't come back on. Also the slider feels different...maybe looser a bit but also binds sometimes but you can push through it.

I pulled into a gas station and thought the cable or lever disconnected from the heater control valve but I can see it moving as my passenger moved the heat selector from cold to hot. It looked to have full range of motion.

Any ideas? Could the valve have broken inside? The engine was up to temp and it stayed normal during the drive. Now my wipers freeze and won't clean the windshield...please help!

Thanks,
Dave

arlindsay1992

iTrader: (8)

The temperature slider has two cables connected to it, one goes out through the firewall and opens the heater control valve. The other goes to a flapper door to direct air either through the heater core or around it behind the dash. The cable for that one connects near the floor behind the radio. You access it from the passenger footwell. Crawl under there and see if you can find anything fishy.

Davebarbier

Ah, good to know. Thanks arlindsay, I'll report back!

Davebarbier

You were completely right. But the cable is attached and pulls the lever properly to the cold position but it doesn't push it. I can push it with my hand, though. Something is preventing the cable from being able to pull the lever. The lever in the dash isn't stuck, it feels smooth. It feels like the problem is on the hot/cold slider selector end.

Thanks for the help! Now to dive in to the dash.

arlindsay1992

iTrader: (8)

You can disconnect the cable from the flapper door and see if the door moves freely by hand.

You might have broken the cable at the Z bend where it connects to the control lever. I think you can see it if you remove the radio surround and radio.

When I was installing my new/used heater control assembly (my original one broke at the pivot for the temp slider) all the cables were pretty gummed up. I sprayed some brake parts cleaner in them and worked them back and forth until they freed up then blew compressed air through them. Finally I lubed them up with silicone spray. All the controls work like butter now. It's unlikely to cause a total failure, more likely to just gum things up, but you might look into cleaning them if you have it all apart.

Davebarbier

I'll do that, thanks for the help. Glad I still have heat when it's supposed to be in the negatives at night soon, ha.

Davebarbier

Ok, back at this. I put this on hold because I was able to slide it to the heat section by hand down at the footwell. But now that it's getting warmer I need to be able to adjust it at will.

I have the dash apart a little and I see the connection. I just have a question how the white ferrule/connection thing is supposed to be held on by the little black plastic bracket. I took some pictures and also drew a little simplified diagram. To me it seems like the white ferrule got dislodged and is just free to move around when I slide the heat selector. I tried to push it back in but it's really tight so it's not easy to do. Anyone have a picture of this on a working truck?

In my drawn diagram it's currently like the top one but I think it should be like the bottom one. Is that true?

Thanks in advance!

dropzone

iTrader: (6)

this might have what you need
http://tacoma.site40.net/4Runner_90-...e/ac/airco.pdf

Davebarbier

Hmm, thanks Dropzone but I think I came up with a remedy. I made a metal clip to slide up into the black plastic bracket to hold the white ferrule in place. Seems to work well.

I'm checking out that link and it's hard to see the diagrams in detail but I'll refer to this if my makeshift clip fails.

Thanks!

Oh, here's a picture of my clip installed.

dropzone

iTrader: (6)

looks like your solution will do the trick.