2nd Gen Non-Engine/Transmission Hot Air

[darkhorse]

I'm having problems with my heating/air conditioning system. The condensation drain was plugged. I cleared that & got nearly a gallon of water to drain out. Immediately after that the system put out hot air & no response to the heat control knob. The A/C condenser still gets cold but the blend door seems to be stuck in the hot position. It's actuator is electric but I haven't been able to locate a fuse for it but I don't see any blown fuses anywhere. Any ideas any one?

 

[darkhorse]

golly, 78 view & no ideas posted. . I guess motor heads don't necessarily do A/. It looks like to get at the blend door & it's actuator, the whole HVAC unit needs to come out. Since that means opening the A/C lines I'm taking it to a dealer Thuresday.

 

[RBallard]

I had problems with my HVAC so let me tell you what I found.



If your blend door isn't operating - moving, it could be two things. A dead servo or the plastic key broke.



Try this, key on your ignition and turn off the everything including the fan. Rotate your know from cold to hot and listen and look under the passenger side of the dash to see if the servo is operating. If it is, then your plastic key broke. If you remove the screws in the servo housing (I think it's two) and you'll need an S styled screw driver because it is TIGHT. When your servo housing drops down you should see a plastic adapter. It is normally keyed to the blend door shaft. When mine sheared it ruined the adapter as well. A new adapter is around $12 at the dealer but for what ever reason it doesn't include the key. I ended using my new plastic one to create a brass one that won't require a key. I will say this, the alignment of the keyed shaft and adapter is CRITICAL. My neighbor, a Chrysler mechanic, lead me to believe that this system was intelligent and that it self centered. BS. One of the gears in the servo housing has a wiper which indicates it's position. You can take it apart and position anywhere you want but when you connect everything up, it goes to the position selected on the controls.



If you don't get any movement from the actuator, then the motor is probably dead. I have an extra one here - they are $115 from the dealer - I have $50 in mine.



Hope this helps, let me know if I can help any further



Bob

 

[RBallard]

top view

 

[darkhorse]

Thanks, Bob. It's acting like it's the servo motor that's dead. I can see the shaft you have marked with the white & red lines. it doesn't move. I'll try removing it tomorrow.

 

[RBallard]

If you would like, send me your address and I'll ship it to you. Plug it in and try it out, at least then you'll know with out spending big bucks. If it doesn't work just ship it back and it must be in your temperature controller. I just sold my extra temp controller on ebay. We had the DRBIII hooked up to the truck thinking there was a control module where we could program the position but no luck. There are actually only a few control modules onbaord the truck, there wasn't a heck of lot I could change but did happen to turn on the 3 cylinder option.

 

[darkhorse]

That's a generous offer Bob. I'll try pulling the servo motor later this morning. I'll PM you later.



Is that 3 cylinder option something for idleing? It seems to me I read something about it once.

 

[RBallard]

Yep, the cold weather option. Not sure if it will ever be used as I generally keep the truck plugged in.



If you want I can priority mail tomorrow and be there in 3 days.

 

[darkhorse]

Bob, you'r right about the fit of the servo screws being tight! I'm wondering how I'm going to get the back one back in . There's little doubt what went wrong now. The bottom 1/3 of the servo housing was full of water, presumably from my clogged condenser drain. It's funny how the water got in there when I unplugged the drain. I've got the little electric motor from the servo out in the sun now. Maybe I'll get lucky & it will work when it's dry. If not I'll have you send me your spare.



Thanks for the help. It's saving me the bundle of $$ I would have $pent at the dealer'$

 

[darkhorse]

good news & bad news

First the bad news. No life in the servo motor. The good news is I can flop the blend door by hand so I don't have to blow hot air or nothing. There's no blending though. It's all hot or all cold. I can deal with that 'till I get a new servo motor.

 

[darkhorse]

the reason why

I discovered how my A/C drain got plugged in the first place, trapping the water that ended up in the servo motor. I have a lot of insects around my place. today I caught a wasp laying an egg in one of the zeros on my Ram 2500 name plate. There was also another one in the door handle to the battery box on the horse trailer. I take it that explains the dirt in the A/C drain. Dang buggers!

 

[RBallard]

Believe it or not I got it down to a 10 minute job. After taking the joker out a dozen I got easy. The back screw is the worse. I peeled the carpet out of the way and used this screw driver. I put the screw on the end and pushed down on the padding and angled it to get the tip in. Then spent along time screwing since you only get a quarter turn.

 

[darkhorse]

Bob, I just happened to have a screw driver just like that in the bottom of an old tool box. I too could only get a 1/4 turn at a time. It's a bit of a PITA but better than $55/hour at the dealer having them remove the whole HVAC. That's what I would have been doing this morning if you hadn't chimed in & told me it can be removed with the HVAC in place. The TDR is pretty cool!!

 

[BlowinBlackSmoke]

A/C is a pain in the ass when it goes out the windows and just gunna stay down and ill drive a little faster!