04 Limited Climate Control issue

[nicheel8]

I have a 2004 2WD, V8, Limited with automatic climate control and its acting weird.

I live in AZ and it was 94 degrees today. So when turn on the AC and press "Auto" it works fine. As soon as I started to raise the temp from "LO" to 65, 66, etc. the heater kicks on. If I put it back to LO it blows cold air again.

Doesn't matter if I change the Driver or Passenger Temp it will blow hot air on that side. The only time it blows any cold air is when the the display is set to LO.

Any ideas?????

 

[nicheel8]

Bump

 

[CXS]

I didn't have the same issue but, since nobody is replying, I'll mention that I had a circuit board section fry for some reason. I replaced mine and all's good now.

 

[nicheel8]

I didn't have the same issue but, since nobody is replying, I'll mention that I had a circuit board section fry for some reason. I replaced mine and all's good now.

Where is the circuit board located?

 

[mizak82]

id guess its the air/mix servo (happened in my lexus) or the switch/circuit board in the HVAC is malfunctioning..

have you been hearing clicking or grinding noises coming from the dash lately?

 

[nicheel8]

id guess its the air/mix servo (happened in my lexus) or the switch/circuit board in the HVAC is malfunctioning..

have you been hearing clicking or grinding noises coming from the dash lately?

No clicking or grinding. Just blowing hot air/heater whenever I raise the temp above "LO"

A new symptom today. Auto light does not turn off after I change manual flows.

 

[CXS]

Where is the circuit board located?

Pull the HVAC panel (easy) and the circuit is in the top section. My problem was evident since there was a black/burned section.