Rep Power: 0

I've just replaced the radio in my car and now tonight, when driving home, the car got really hot inside. When I dialed the temp gauge down to cool area, it continued to blow hot air into the car.
I'm up here in Canada where is was pretty frosty tonight, but having the heat on max no matter where the dial is pointing is not a good thing.
All connections from the radio install seem fine and were working okay earlier.

Thoughts?

 
Rep Power: 812

might have blown a fuse, it sounds like the temp switch is broken tho. check the fuses just in case. you may need to get a new module that has the dials and swap it in. hmm oh you plugged in the connectors when you put everything back right? theres one for the dials and one for the buttons. does the fan speed and position work?

 
Rep Power: 0

Everything is plugged back in - both the vent selection switch and the fan speed dial are working fine. Just the heat - just hot, but was working fine this afternoon when I tested everything out after installation.

 
Rep Power: 812

hmm, well put the fan on the lowest speed (not off) and put your ear up against the vents. turn the dial from full cold to full hot and you should hear some noises from the flap closing and opening for several seconds. if nothing, its prolly a bad temp switch. it could just be coincidence that it happened today.

 
Rep Power: 0

What's the dealio is it is a bad temp switch? That a DIY or a mechanic sorta thing. Any idea cost?

Thanks for the advice...I will go listen in the AM and hear what I can hear.

 
Rep Power: 812

well its pretty easy, you just find another console piece on ebay (all you really need is the module with the dials) and swap it in. when you have the console out, the dial module comes off from behind with a few screws. pull the ***** out from the front first tho. then change with the new piece, screw back in, and plug the connector. you can even try to open up the old one and check for problems with the circuit board and clean the metal contacts with qtips and alcohol.

 
Rep Power: 308

If this is a 7th gen Civic the water valve is located near the middle of the car on the firewall it has a blue linkage cable attached. It should open and close as you work the temp selector back and forth (my guess is that it is not closing to shut off heat)

Here is the test procedure for the 01-05s:

The heater control panel has a self-diagnosis function. To run the self diagnosis function, do the following:

1. Turn the fan switch OFF

2. Press and hold the recirculation control switch and the rear window defogger switch down.

3. Turn the ignition switch oN ll

4. Release both switches. The recirculation indicator and the rear window defogger indicator come on. The recirculation indicator goes off 3 seconds later and the A/C indicator comes on. then the self-diagnosis will begin. About 10 seconds later, the self-diagnosis will finish and the A/C indicator goes off.

If any trouble is found. the recirculation indicator blinks the diagnostic trouble code (DTC) to indicate a faulty circuit or component.

If the system is OK, the recirculation indicator stays off.
Here are what the fault codes mean.

7 An open in the air mix control motor circuit

8 A short ln the air mix control motor circuit

9 A problem in the air mix control linkaqe, door, or motor

10 An open or shon in the mode control motor circuit

11 A problem in the mode control linkage, doors, or motor

12 A problem in the blower motor circuit

13 A problem in the EEPROM in the heater control panel; the control panel must be replaced

14 An open in the evaporator temperature sensor circuit

15 A short in the evaporator temperature sensor circuit

In case of multiple problems, the recirculation indicator will indicate only the DTC with the least number of blinks.

In case of an intermittent failure, the heater control panel will store the DTC until the ignition is turned off.

 
Rep Power: 0

I tried this and it did not work. Can you verify the steps are accurate? I held the buttons and turned the car to On II. The fan was off. When I turned to on II the fan came on full blast but the only light on was the rear defrost. Fan stayed on and on high till I touched something and then it shut down as per the switch. So, doing this did do something....it just didn't do any diagnosis along the lines mentioned above.

 
Rep Power: 308

It worked on my 05, only difference was the defroster light stayed on solid when it was done (no flashing)

Take a look at the valve I mentioned to see if it is moving. Look at the bare wire coming from the blue cable, it has a small loop at the end that should move back and forth as someone cycles the heat control back and forth between min and max settings (car on)

I will double check the test procedure again.