HVAC Temperature Control

[DoneThoo2]

2000 LC. AC and heat work fine. The issues is I either have ice cold or steaming hot air. There is no in between. The temperature control knob, as soon as I turn it warmer than the second indention between 65 and 70 it starts blowing hot air. This is only for the front AC not the rear HVAC.

Any suggestions?

 

[Mark WV]

Two possibilities.

Cabin temp sensor- located lower dash below key switch - pop it out and clean with electrical cleaner. When reinstalling make sure to hook up the little plastic tube which will be hanging loose

2nd -and most expensive -possibility is a bad “ac amplifier”. Basically it is the computer module that runs the automatic temperature control.

On my 03 model with the exact issue you describe it was a bad ac amplifier…

Also do a search on here as other have had different but similar issues with different causes

 

[DoneThoo2]

Two possibilities.

Cabin temp sensor- located lower dash below key switch - pop it out and clean with electrical cleaner. When reinstalling make sure to hook up the little plastic tube which will be hanging loose

2nd -and most expensive -possibility is a bad “ac amplifier”. Basically it is the computer module that runs the automatic temperature control.

On my 03 model with the exact issue you describe it was a bad ac amplifier…

Also do a search on here as other have had different but similar issues with different causes

Hey Mark,

I checked the AC Temp Sensor and it was disconnected. So I took it off and cleaned it up and reinstalled it. AC isn't going from freezing cold to hot as fire anymore. Thanks for the info and fix.

 

[Mark WV]

Glad it worked out for you!

 

[FJKai]

This is exactly what my heater and a/c does. Any additional information about where exactly this sensor is, or what it looks like would be greatly appreciated. I need to look into this also. Thx

 

[DoneThoo2]

If you look where your right knee is under the ignition you will see a small vent. The sensor is attached to that vent. I popped the trim off in front of the speedometer cluster then the large plastic piece around the steering column. I had to also remove the metal framing to find the wire for the sensor. It was tucked in behind the steering column.

 

[FJKai]

If you look where your right knee is under the ignition you will see a small vent. The sensor is attached to that vent. I popped the trim off in front of the speedometer cluster then the large plastic piece around the steering column. I had to also remove the metal framing to find the wire for the sensor. It was tucked in behind the steering column.

I gotcha. Thanks for info. I’ll be looking into it this weekend.

 

[ClassyJalopy]

I gotcha. Thanks for info. I’ll be looking into it this weekend.

So?

 

[Greenbean]

I am thankful for this thread,
I have a 2000 LC lots of miles…

Just had a new Denso compressor installed as the old one was making terrible noises and the A/C light of course flashed inside the cabin and the clutch would disengage.

After the shop did the compressor and bag filter it blows freezing cold now BUT on AUTO you have to be at just a click above 85 on the dial before it stops blowing the ice cold air.

I thought maybe it needed a calibration of sorts. I’m going to check the sensor under the ignition switch there.

The outside temp sensor seems to be accurate, thanks for the above tips.

Seems even on 75 and at 66 ambient outside air it wants to blow ice cold! Hmmm