Two issues... A/C and Radio
 

I'm the owner of an 1993 Buick LeSabre Limited and have two small issues...

#1 - When I press the AUTO button on my heater controls, the ECON button lights up. I cannot get the temperature control to go into Automatic mode. Does this mean the A/C compressor isn't working?

#2 - When I set the radio balace to full LEFT and fader to full FRONT I get no sound at all. Since there is more that once speaker involved I assume that I have a faulty radio, or possibly a bad wire feeding the speakers in that corner. What is most likely the cause? This is a cassette radio with the equalizer.

The best way I can attempt to explain this is;
If the pilot wants the plane to go left and the message doesn't get to the rudder ,the plane will not respond.
The compressor gets the message from the controls and until the cause is found as to why the message is not getting through , the compressor may or may not be functioning.

You did not say if you can or are able to get anything from the right side speakers. How do we stand with them?

For the A/C controls, the AUTO button does beep when I press it. So that seems to be working. It just doesn't switch from ECON mode. I'm going to get the A/C checked later today.

As for the radio, all the other speakers work - Right front and both rear.

There is a good possibility the speaker for the left front has gone out to lunch !

One way to confirm this (without some special tools) is to try the RF speaker at the LF . It might be a little trouble , but that way you will know for sure..

Well... there are two speakers in each door. What are the chances of both failing?

I think I'm going to upgrade the head unit and then deal with the speakers if they turn out to be faulty.

So... as far as the A/C goes, I've tried bypassing the low pressure switch near the compressor and the high pressure switch that is on the compressor but still no change.

Checking the HVAC control diagnostics (Hold OFF and WARM) I get two error codes. A 48 and a 152. No idea what they are yet, but I'm looking.

I'm pretty sure that I have refrigerant in the system. When I attach a gauge it moves from 0 to around 40psi... I don't really trust the gauge though as it's pretty old, but it's all I have.

I should also mention that the system was converted to R134a back in 2003.

A/C Fixed? We will see...
 

So, I disconnected the battery to clear the HVAC error codes.Hooked it all back up and the A/C compressor is cycling now and I can choose AUTO on the HVAC controls. Just to be on the safe side I added a can of stop leak to the A/C system. While adding the sealant the pressure did go up to about 100psi and then slowly tapered off and remained steady at 40psi, which is where it should be from what I've seen online.

Hopefully that cures the A/C issues!

There is a whole history of the internal barriers in R12 hose and R134A hoses that involves sizes of the molecules etc In the absence of a good working gauge you might try adding some refrigerant and feeling the accumulator/dryer top. If all it needed was some addl refrigerant you will notice the top of the accumulator starts getting colder.
You don't want to add too much because it can flood the system and prevent it from cooling..