[donaldp]

I noticed my AC is cold on the drivers side and less cold on the passenger side, when both controls are set to "LO". I tested with a digital thermometer and found the difference was 10 degrees.

If I turn the temp all the way to "Hot" and then back to "LO", then both sides blow cold air.

Any ideas, suggestions on what the issue is or what the remedy is?

[bishopts]

Usually it's a sign of low freon. Not empty, just low.
That being said... my ATS does the same thing if i remote start it and if i move the temp to anything but its coldest setting. For mine its the passenger blend door actuator. It works but the motor in it is weak. So once it's doing the kinda cold but not really cold like yours. I have to leave it on low and after a couple of days and start cycles it will manage to get the blend door all the way closed.
I can't say yours is definitely a blend door actuator like mine is but it sounds like it.
I will try to remember to look up the procedure tomorrow when i get to work for you.

[bishopts]

Also you can try disconnecting the battery for a few mins and then reconnecting it to force the hvac system to relearn door limits.

[donaldp]

Originally Posted by bishopts

Usually it's a sign of low freon. Not empty, just low.
That being said... my ATS does the same thing if i remote start it and if i move the temp to anything but its coldest setting. For mine its the passenger blend door actuator. It works but the motor in it is weak. So once it's doing the kinda cold but not really cold like yours. I have to leave it on low and after a couple of days and start cycles it will manage to get the blend door all the way closed.
I can't say yours is definitely a blend door actuator like mine is but it sounds like it.
I will try to remember to look up the procedure tomorrow when i get to work for you.

Thank you. I look forward to hearing what you find.

[chevy409]

Your passenger blend door actuator is sticking. Cycling hot then cold resets it, but it’ll get worse. Try an HVAC recalibration.

[bishopts]

Originally Posted by donaldp

Thank you. I look forward to hearing what you find.

The labor time for the right actuator is 7.8 hours. The procedure starts with pulling the dash panel off.

You could possibly get access to it from pulling the glovebox assembly out but, i dunno.

[ctrlz]

Originally Posted by chevy409

Your passenger blend door actuator is sticking. Cycling hot then cold resets it, but it’ll get worse. Try an HVAC recalibration.

it's either this or low refrigerant.
I would check duct temps when they are both blowing cold. You may need a probe thermometer to get a good reading. The ones with a dial gauge are like $10 on amazon.
To get an idea of charge, you would need gauges compatible with r1234yf. I have r134a gauges, and I bought a set of adapters for the newer fittings on amazon. r1234yf is ridiculously expensive. I bought 4 Honeywell cans for $100.

[bishopts]

Originally Posted by ctrlz

it's either this or low refrigerant.
I would check duct temps when they are both blowing cold. You may need a probe thermometer to get a good reading. The ones with a dial gauge are like $10 on amazon.
To get an idea of charge, you would need gauges compatible with r1234yf. I have r134a gauges, and I bought a set of adapters for the newer fittings on amazon. r1234yf is ridiculously expensive. I bought 4 Honeywell cans for $100.

I got adapters as well. But i top of cars with 134 instead of 1234yf. Ive been doing it for a couple years now. It saves people money and doesn't seem to affect the system at all.

[donaldp]

Originally Posted by chevy409

Your passenger blend door actuator is sticking. Cycling hot then cold resets it, but it’ll get worse. Try an HVAC recalibration.

How do you perform an HVAC recalibration?

[bishopts]

Use a scanner to recalibrate or disconnect the battery for a few mins and then reconnect it.

[ctrlz]

Originally Posted by bishopts

I got adapters as well. But i top off cars with 134 instead of 1234yf.

There are some issues and "potential" issues with this. I've read that some service facilities will not touch an r1234yf system if r134a has been added. Certainly I would not do this on a car still under warranty.
I have a honda with a slow leak and have been recharging with the yf once per year. It's a very small leak and I don't have a good dye stain anywhere (yet).
https://top-refrigerants.com/en/can-...r1234yf-system

[bishopts]

Originally Posted by ctrlz

There are some issues and "potential" issues with this. I've read that some service facilities will not touch an r1234yf system if r134a has been added. Certainly I would not do this on a car still under warranty.
I have a honda with a slow leak and have been recharging with the yf once per year. It's a very small leak and I don't have a good dye stain anywhere (yet).
https://top-refrigerants.com/en/can-...r1234yf-system

I see hondas leak through the rubber hoses more than other makes. But the most common leak between all makes ive see is the service ports.

[ctrlz]

Originally Posted by bishopts

I see hondas leak through the rubber hoses more than other makes. But the most common leak between all makes ive see is the service ports.

There's an intermediate hose which tops my list of suspects. I am watching it for now because the leak is so slow. There is an extended warranty for the compressor which (rarely) leaks at the shaft seal. Honda charges almost $300 for a recharge with dye, which I did for like $60.

[12GoFast]

Had this problem with mine, except drivers side blew hot. Dealership replaced the door motor on ducting. Saw no signs of them pulling the dash, and was done in one day. It was done under warranty