Hey everyone, first post and need help or guidance.

My 06 nissan quest s blows cold air through the front vents, the rear heat seems to work fine however.

I replaced my valves covers front and back last month so i thought maybe i had somehow gotten air in my system, so i jacked up the front topped off the radiator and revved about 2500 rpm for several minutes while squeezing the hoses. I got a few air bubbles out, topped back off and let run for about an hour with the radiator cap off and the level didnt lower anymore. Ive drove it for a few days and the level in the overflow hasn't changed and the coolant level is at the top of the radiator still, im pretty sure ive gotten all the air out?...i hope.

So next i turned my attention to the heater control valve and heater core hoses. With a mulitmeter im getting 12 volts to the valve when heater is on and nothing when its off, as i would expect. With the heater off, one hose isnt nearly as hot as the other and when its on they are both really hot and i can feel coolant flowing, i assume this is normal operation.?

So now im thinking blend door actuator or possibly the A/C/Heater controls themselves are to blame.
I already had to replace one actuator for the mode door i believe it was because it was making the extremely common annoying clicking sound.
So my next question, wouldn't i hear the same sound if the blend door actuator had failed? Wouldn't I at least hear the movement of it even if it was working properly? Currently when i change the temperature dial from heat to cold and vise versa it's complete silence. I don't think that's normal and that why im leaning toward the temperature a/c control's themselves.
I have an Autel scanner that i can monitor some live data with. When connected i have all the available items below. Im not sure which ones correspond to the front temperature dial but when i turn it one way or the other i get no voltage changes indicated by my scanner on any of the below items.
The rear temperature dial however does have one of the tempset volatges change and one of the FDBCK voltages change.
I ordered new ac contols based off what i found.
Has anyone had this problem? or could recommended further troubleshooting tips? Any input is appreciated
Thanks!



BATT VIA CAN "V" Displays battery voltage signal.
IGN VIA CAN "ON/OFF" Displays ignition switch signal.
DVR SUNLD SEN "W/M2" Displays optical sensor (driver) signal.
PAS SUNLD SEN "W/M2" Displays optical sensor (passenger) signal.
AMB TEMP SEN "°C/°F" Displays ambient temperature sensor signal.
EVAP TEMP SEN "°C/°F" Displays intake sensor signal.
INCAR TMP SEN "°C/°F" Displays in-vehicle temperature sensor signal.
RR TEMPSET FR "V" Displays air mix door (front) set point signal.
RR TEMPSET RR "V" Displays air mix door (rear) set point signal.
MODE FDBCK "V" Displays mode door motor feedback signal.
DVR MIX FDBCK "V" Displays intake door motor (driver) feedback signal.
PAS MIX FDBCK "V" Displays intake door motor (passenger) feedback signal.
RR FDBCK "V" Displays air mix door motor (rear) feedback signal.
RECIRC "ON/OFF" Displays recirculation switch signal.
DEFROST "V" Displays defroster switch signal.
AUTO "ON/OFF" Displays AUTO switch signal.
A/C "ON/OFF" Displays A/C switch signal.
MODE "ON/OFF" Displays MODE dial signal.
L TEMP UP "ON/OFF" Displays driver side temperature cont

'RR TEMPSET FR "V" Displays air mix door (front) set point signal.'

That one needs to change for the front I'd bet.

Thanks, yeah, it dosen't indicate any voltage changes when i rotate the temp dial, none of them do for that matter. When i get the new controls ill update. One thing worth mentioning is the FSM showed a quest version with dual climate contol and auto settings. Mine dosent have any of that.

You seem to be at war with yourself...........saying 'none of them do' after saying this...

'The rear temperature dial however does have one of the tempset volatges change and one of the FDBCK voltages change.'

"None of them do" is in reference to voltages being changed when rotating the front temperature control dial
After a little more observation i have noticed that RR TEMPSET FR voltage changes with the front temperature dial controlling the rear heat and RR TEMPSET RR voltage changes when i rotate the temp set dial on the headliner.
Other nissan FSMs use DVR MIX FDBCK for troubleshooting the front temperature control dial.Since i have no voltage change there, I feel like im still on the right track with the new controls.

It may well be that too much heat going to the rear may cut heat going to the front..........I'd hate to think that I had a system design limited enough that I had to cut max volume back just to get some heat. I would want both volume AND heat myself.

Found the problem, It was me. Previously i mentioned i had already changed one actuator due to it making the common clinking noise. I thought it was the mode door but apparently it was the air mix door or blend door that i replaced,(temp change) I didn't really pay attention at the time just wanted the noise gone.Well, I bought the wrong actuator. It looked identical to the one that it replaced but after troubleshooting today i figured out it wasn't. The one that i replaced it with only had 2 pins in the connector the proper one has 5.