AC warm zone/cold zone

[armcomdes]

My 2007 Lexus ES350 (105k miles) has the AC putting out warm air to the driver side while cool comes out the passenger side. The car is equipped with a Dual Zone capability. But this is happening when dual zone is off and the unit is set at "LO" or the coldest setting.

I thought maybe a system recharge is in order but one side is very cold. Maybe a fuse/relay/rubber pressure tube?

[gbhrps]

armcomdes,

Your system may have one of two issues causing it. The first is easy, just pull the HVAC fuse, or disconnect the battery for 20 minutes or so. Either one will reset the HVAC computer to factory specs and things should work as normal IF ... the door actator on the driver's side hasn't died or the door itself become jammed/broken.

 

The second fix, as I alluded to above, involves tearing apart a good chunk of the center console in some cars, in order to get at the HVAC air box and its related actuator motors and wiring harnesses. At this point you'll need to decide whether to try a fix yourself, or leave it to a good independent mechanic (who'll be cheaper than a Lexus tech). Good Luck!

[armcomdes]

Pulled the fuse for the AC and it did not help the problem. So it looks like a fix is in order. Would love to get my hands on a step by step. Haynes/Chilton don't address this type of issue, especially taking apart the console.

It's too bad. The issues comes and goes. Wish it were a maple seed that eventually un-lodges itself.

[armcomdes]

On 7/8/2016 at 8:14 PM, gbhrps said:

The second fix, as I alluded to above, involves tearing apart a good chunk of the center console in some cars, in order to get at the HVAC air box and its related actuator motors and wiring harnesses. At this point you'll need to decide whether to try a fix yourself, or leave it to a good independent mechanic (who'll be cheaper than a Lexus tech). Good Luck!

I'm in northern NJ. Any recommendations of a good mechanic to do this work?

[TrevC]

I know on Honda climate control there is a reset procedure for the electronic panel to power down and recalibrate the settings when powering back up (done by holding demist button and pressing fan speed button several times, if I remember correctly)....not too sure if Lexus has this facility?

Also, worth checking all the vents are actually open and allowing the cold air flow through them.

Regards   Trevor - Moderator

[armcomdes]

Trevor

When the system is on with both zones set to "LO" (which is the coldest) the Passenger Center Vent blows cold and the Driver Center Vent blows warm. Because of the Dual Zone feature, the two side by side vent can be set to different temps. But it doesn't matter if the Dual botton is pressed or not, warm air continues to blow on the passenger side.

I've already pulled the fuse for the AC and waited 25 minutes as one post suggested. I will search the internet for what you said of the Honda.

[armcomdes]

After contacting an good mechanic and also my Lexus dealership, I opted to have the dealership have a look. They did a recharge which included a tracer for leaks (@ $210). The A/C is performing like new, so it wasn't a blend door after all. If the A/C continues to work well, we're done. If there are leaks, it could be as easy as tightening a connection, or replacing a major system part.

Thanks to all that gave me advise.