Running the Automatic Climate Control test...

[Speedmaster]

So, I am new to this forum. Just started downloading manuals, etc. and went to start my first project; testing the auto climate control. I ran both tests per manual and my system responded to neither...as in, it did zero analysis. I did note that the mechanism sounded like it was working (loud, but operable).

Any ideas on how to proceed?

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Ugh...operator error. I didn't hook up the testing device. I expected it cycle through and display on the unit itself.

 

[captngaryr]

I found the test to be confusing as well
Gary

 

[ftuhy]

When I ran the test, per page 22-12 of the 1991-1996 manual, I found there was little margin in "push both the AUTO and OFF buttons on the control unit at the same time". I used my thumbs to make sure it was a simultaneous push.

And it is a slow process;
set temp to 61, hit both buttons, wait a minute
set temp to 62, hit both buttons, wait a minute
set temp to 63, hit both buttons, wait a minute
ad naseum all the way up to 90 degrees

All the results are read out on the CCS faceplate, so, Speedmaster, I'm not sure what "testing device" you are referring to. The picture on the manual page shows what icon lights up on the faceplate to indicate what component of the system is having a problem.

Perhaps BrianK can offer more insight on this.

 

[JD Cross]

I expected it cycle through and display on the unit itself.

Are you running the system checks on pages 22-12 and 22-13.
If you are, the results are shown on the face of the CCU.
What testing device are you referring to in your post?

I'm assuming your climate control system is not working properly
You don't state your car year but if it's an early 90's vintage it's likely easiest to remove the CCU and send it to BrianK.
He'll check it out and repair what's needed.
Many of us have found the CCU's to need a repair after 20 years or so.
It's a well known item.

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Looks like Frank replied while I was typing out my reply. :smile:
Same questions on the testing device and both agree Briank is the CCU guru.

 

[Speedmaster]

So on page 22-2 of the Climate Control Troubleshooter, special tool "ECU Test Harness" is mentioned. Now I see the corresponding Page Reference and realize it is not applicable here.
Still, my CCU display does not throw any error codes. I ran it up and down the temp range and heard the door flap open, close, etc. Maybe my CCU is fine. Who knows. It just felt like an oven in the car the other day (80+ degree day, no a/c, black car) and I assumed the system was allowing hot air to enter from the heater core. Maybe it was hot air, but just ambient hot air. Ha!

 

[JD Cross]

Is the problem that your A/C doesn't work?
If you are not getting cold air it could be your CCU or your A/C system has a leak.
Could you elaborate on exactly what the problem is, and the year of your car to help narrow it down

 

[Speedmaster]

JD thanks. Not trying to solve for a/c yet (thought it seems like you may be hinting that without a/c the cabin will get hot anyway). I know the a/c is not hooked up (belt unattached). I will get the guys at ProjectX to look over the system as I don't want to monkey around with ruining a compressor unnecessarily.

The car is a 1991.

All components seem to be there.

The CCU does not seem to show codes or cycle through the test using either test per manual.

The CCU does seem to be opening the flap and changing air speed as well as temp okay though.

Hope this helps.

 

[Briank]

Most likely the freon has leaked or been let out of the system.

 

[jwmelvin]

At least in my car, the air coming in will never be quite as cool as ambient when AC is off, even with temp to full cool.

 

[JD Cross]

The car is a 1991.
The CCU does not seem to show codes or cycle through the test using either test per manual.
The CCU does seem to be opening the flap and changing air speed as well as temp okay though.

I have a 91 black and at this time of year you really need the A/C running properly or the car becomes an oven.
I'll share my A/C repair story to point out what I did wrong and what I would do today if I had a do-over.

My A/C stopped working in 2011.

I removed the CCU circuit board and sent it to BrianK for repairs and all was well for a while.
In 2012 I installed Cantrell headers and here was mistake #1. Installing headers is a big job and the A/C compressor was right there......
Anyway in 2013 my R12 A/C system stopped working again and checking the sight glass in front of the radiator I could see the system was empty.
I took the car to the A/C shop the Acura dealer used for conversions and had them check the system for leaks, install the Honda r134a retrofit kit, and refill the system.
This worked fine until I drove to NSXPO 2013 in Raleigh where on the return trip I started hearing a whirring sound when I had the A/C on.
This was the A/C compressor beginning to fail so I had to drain the system, remove the front header, replace the compressor and recharge the system.
Now I have a rebuilt CCU, an r134a converted system, a new compressor and it blows ice cubes so all is well and should be indefinitely.

Looking back here's what I should have done.

When my A/C CCU first went on the fritz I should have concluded, I had a 20 year old R12 system that was starting to fail.
When I did the headers I should have, at that time, drained the system, installed the OEM r34a retrofit kit, installed a new compressor, refilled the system, and been done with it.
It would have saved me much money, and much time.

So were I in your shoes today I'd remove the CCU circuit board, send it to BrianK, and get that behind you.
Then I'd have the R12 drained, test the system for leaks, have any leaks repaired, and install the OEM r134a retrofit kit.
Then I'd remove the old compressor, install a new one, fill the system with r134a, and enjoy 20 more years of nice cold A/C.

And while I had the lower beam etc. out for the A/C compressor change, I'd install headers if you don't already have them.

Sorry for the long winded reply but if you have the $, then bite the bullet, get the system re-done, and you'll be way ahead.