ICGS3

My problem is that there is NO heat on the drivers side at all...it only blows cool air. Now the passenger side blows hot air. When I do use the A/C I get cold air on both sides in every mode. And when I put the heat on all the heat blows on the passenger side only on every mode. Now my bro in law says that he changed 3 servos and he says, "the right, middle and left side" do I know what he means? No. I opened up driver side and passenger side to see atleast visually see if the servos move. I saw that "Air Mix Control Serv Motor (Driver Side)" is working, I also saw the "Air Vent Mode Control Servo Motor" is working, and the "Air Inlet Control Servo Motor" working. Now when it comes to the "Air Mix Control Servo Motor (Passenger Side) it is being blocked so I can't see it if it operating. I also flushed out the heater core.Does anyone have an idea anything besides the servos?

clos430

iTrader: (21)

Is your car reaching normal coolant temperature readings on the gauge ?

ICGS3

Yeah it is reaching normal coolant temperature.

sakataj

iTrader: (182)

So did HE change all 3 on the right side or 2 on the right side and one on the left? if so he didnt change the drivers one....did he plug the plug back into the correct plug?

in all modes, does it blow cool air? in any modes it DOES function correctly?

thread # 100 million on servos btw....

ICGS3

He changed the driver side and 2 on the passenger side. and yes in all modes it blows cool air on the driver side only.

sakataj

iTrader: (182)

so the passenger side DOES have heat? then it sounds like he didnt actually replace the drivers side, didnt do it correctly, or for some crazy reason it went out again....

not exactly related but have you ever changed the thermostat and topped off radiator fluid?

xtremex626

iTrader: (3)

this may sound dumb.. but make sure you check your coolant level. i never checked mine since i bought it (didn't think there would be no coolant in there).. and it was almost near/completely empty.. so i was wondering why my car never blew hot air whenever i left it at 85 degrees on both sides.. added coolant to the full mark and now the heater blows hot at 85 degrees! i always thought my servos were messed up but it turned out to be that it needed more coolant.

ICGS3

thats the first thing I did.

ICGS3

does anyone know what the "Air Mix Servo" do?

ICGS3

I also just realized something....if you put the heat 85 degrees on both sides and press the a/c button that the driver side will blow cold air and the passenger will blow hot air.

smalldog

Hello ICGS3 .
Did you ever figure out your problem? Im' having the same issue on a 99 gs300. I haven't changed any servos yet because they all work (opening and closing) when I change temp and mode?

Mcon

iTrader: (1)

In my case was low freon. I put a freon (refill) and ready. Everything returns to work as it should.

Mcon

iTrader: (1)

I went back to read the entire thread and I know is just a little old. LOL But I read that your brother in law had changed all your servo motors. The two plugs of the servo passenger side are equal when you connected. Both plugs have the same shape and pins inside, but the color is what changes. The plug of the servo (air mix) to the central window of the console, passenger side is Black. The plug of the servo mode, the plug color is White. I just think that the plugs can be exchanged. Check the positions of the plugs, the plugs are invested perhaps even you've seen the work are the two servos. That may be is your problem.

01GSGUy

I am having the same issue, I only get heat from passenger side, even the middle center vent blows hot on the right center, and cold on the one to the left of it... super frustrated. I followed all the suggestions, I took the glove box off and i can physically see all 3 servos working the one on drivers side works too.. what the heck can this be????? I am cold on drivers side... help AND YES MY COOLANT IS CLEAN AND FULL

bratpane

I just wanted to add my experience with this for people to find. After searching like crazy to find out why I had cool air on the left, and warm air on the right, I figured I had to have a bad servo (after first making sure it was full of coolant of course). I took everything apart so I could watch them operate, and everything looked ok to me. Still people said, when in doubt, change all the servos, who cares if it costs $600, do them all or don't come back with questions. I didn't change mine, but finally decided to simply flush the heater core, and now I have all the heat again. I realize that the servos do go bad, but if they look to be working try the flush. It's free and might be all that is needed.