dhonsey1

I have a 2000 Tahoe LT with the 5.3. I have had no heat in the front but the rear heat works just fine. This has been going on all winter and i finally got sick of it and started to tear into it because i was told that it was probably an actuator. But there are 3 of them in this model. I have 3/4 of the dash off so i can try and get to it but it looks like it is a pain in the ***. If anyone has had this problem and knows anything about it or if i am on the wrong track i would love any info on this subject. Also if there is an easier way to get to the actuator that would reallly help also.

RacerX

Well, you gotta isolate your problem before you start taking junk apart. When you say you have no heat. Do you mean no air distribution and from where? Does the blower motor work?

dhonsey1

yes the blower motor works just fine but there is no heat in the front. the rear heat works great. and the only reason i started taking stuff apart is because i have nothing but time for this week so i wanted to test the actuators and try and get it fixed while i have this time off.. but as i tore into it it looks like there not very easy to get to. i have diagrams and everything but i was just trying to see if i am doing alot of unessasary removel or maybe in over my head or the easiest way to go about this whole thing. thanks for the help

73shark

Is the coolant leaving the front heater core hot as soon as the inlet? May have a clogged core if it isn't.

dhonsey1

I dont know for sure the two black hoses that run through the firewall are bot the same temp. If that means anything otherwise if there is a different way to check the front heatercore let me know?

dhonsey1

I was trying to test the temp. actuator/motor and when i turn the temp dial the motor only turns about a 1/8 of an inch. could anyone tell me if when i do that if it should turn more or what is the best way to test that?

dhonsey1

this may seem like a dumb question but there is only 1 heater core for both the front and rear?

RacerX

Ok same temp, cool but are they both HOT though? If so, the heater core is good. And you hear blower motor so we ll say that works. Ok, lets see here. For sure your CCP is electronic. So first thing first is when you work the dials do you hear ANYTHING move? There are 2 or 3 actuators in the dash. One is behind the glove box(you ll have to pull the glove box out to see it, bring a flashlight). One should be right behind the ash tray by your right calf on the lower part of the dash and the 3rd one if it has one is most likely in the area right behind the radio.

Now you have to determine if they are getting a signal from the CCP and if so, which one is moving and which one isnt.

The one on the lower dash by your leg only does air distribution(3). The one behind the radio maybe does air distribution to the windshield & vents or temperature control(2). The one behind the glove box should be for blend door(1). IF this one doesnt work you cant heat into the car because essentially you cant divert air past the heater core. If the 2nd one doesnt work you cant get the move the temp. control to hot OR wont push air in the direction you want to, same as the 3rd one. BUT the default setting if something broke is to divert air to the windshield. To assist the driver in bad weather from fogging. So that eliminates the 2 & 3rd one. But if 1 is bad then you wont get heat in any circumstance.

Of course all this would mean your CCP works. Work the functions and listen for doors moving and try to isolate where the sound are coming from and see if you get any airflow and from where.

You got it?

RacerX

Well if it moves an 1/8 of an inch it depends on what is it moving from. Like 78 to 82 degrees would be something like that, and that is ok. But something like 60 to 90 degrees it should move in a greater range than that. The armature should move in a range a little greater than 90 degrees(right angle) from max. cold to max. hot. If it doesnt move at all, it may be seized. That does happen. I think the screws are like 4mm or 3mm.

The other question: Are there 2 heater cores? I dont know. Ford uses 2 in the passenger vans and run hoses from the radiator to a plenum in the rear. You ll have to crawl under the car and follow the hoses. But you just may. Rear controls also indicate that you may have a rear evaporator also.

dhonsey1

Thanks for all of that and here is what i have done..... The actuator on the floor i have taken off and run manually and i cant seem to get good heat that way and that according to my diagrams is the temp motor/actuator. the one behind the glovebox i can see and it does move when i hit the buttons that have the arrow for bringing in fresh air or recirculation. and according to my diagram that is the air inlet actuator also they have it named as the recirculation actuator. The 3rd actuator according to my diagram runs the door to wsitch from def. to floor ect. and all of that works just fine as well as the blower motor but 4 some reason i just cant get heat. and yes both lines are the same temp going and coming from the heater core. thanks 4 the help