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Tesla HVAC - When using heat drivers side hot and passenger side cold

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Hey guys,

2012 Tesla Model S

I've been trying to figure this issue out for a while and I'm wondering if anyone experienced anything similar. The A/C works fine (cold on both sides) but when using heat, only the drivers side gets hot but the passengers side blows cold (max A/C like) air. I've taken the car to Tesla and initially had the front passenger temperature actuator replaced. The old actuator was chipped but it did not solve the issue. Tesla then diagnosed it as a failing PTC heater.

I bought a new 3rd gen PTC heater online and had a third party shop change it because Tesla won't change it unless I buy it from them. The issue still persists and now the HVAC makes a slight whistling sound like a kettle boiling slowly. I've read other owners having the whistling issue with their new Model 3's and it just went away over time. Can this be related to the PTC heater or is there somewhere else it can be coming from? I've tried playing with the cabin filter which was likely removed during the PTC replacement but it hasn't helped. I don't think it's related to the PTC because the noise happens even when the A/C is on unless all air passes through the PTC whether it's A/C or heat and it'll hopefully correct itself over time?

Tesla refuses to move past the PTC heater diagnostic. They said if I bring the car back to them I need to buy and replace the PTC heater with them before continuing their diagnostic. They won't refund me for a misdiagnosis either despite them being unwilling to continue. I'm pretty sure the PTC isn't the problem so I'm not willing to fork out thousands because they also won't refund me anything if it doesn't fix the issue.

Anyone else have this issue or know how to proceed from here regarding either the faint whistling noise or heat coming from the drivers side only? The passenger side blows freezing cold air like the A/C is on max despite what temperature I got the heat on while the drivers side blows hot air but not as hot as it should be even on max heat.

Thanks!
 
It sounds like ur actuator for passenger side died n stuck in cold position
do u have codes in service mode?
does pass side always AC cold or outside cold if u manually turn off AC?

No codes in service mode anymore.

Used to have the THC_d0021_RCCMActuator code. I had Tesla replace the front passenger temperature actuator and then the code went away but it didn't help fix the issue. Is there another passenger side actuator? I believe that should be the one Tesla replaced for me.

Passenger side is always cold I believe, maybe less if I manually turn off A/C but it won't get warm on the passenger side no matter what I do.
 
If they replaced it then maybe the actuator door has issue, either stuck or broken
According to epc, only one for each side to control temp
If u can get to it, then remove actuator n try moving door by hand n see if u get heat
There's only one ptc heater as I'm aware...
 
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If they replaced it then maybe the actuator door has issue, either stuck or broken
According to epc, only one for each side to control temp
If u can get to it, then remove actuator n try moving door by hand n see if u get heat
There's only one ptc heater as I'm aware...

Assuming the actuator door is broken, can it be replaced?

When I check the EPC by Tesla, there's no actuator door. It was something I was thinking also but I was hopeful if the door was broken Tesla would have informed me when changing it - but with my history with them it's usually bottom of the barrel work. I will check the door myself or with another mechanic. Do you know what the recourse is if the door is stuck or broken?

I meant if there's another actuator for the passenger side. There's only one PTC heater.

Thanks for your insight on this!
 
I've never seen one in person but it looks like there's intermediary plastic gears/pieces..
For ex. these are common failure point on Jeep that i had to replace...
Its also quite possible it got misaligned during replacement (maybe watch its operation 1st before taking apart)
If the actual door or shaft is broken then u might be out of luck...
I did read on Jeep forum that some ppl had success drilling a small hole in the shaft n securing that plastic piece with a screw (last resort)

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