Generally no Air conditioning in my 2003 Honda Accord Coupe EX-L 3.0L V6. The compressor comes on for a short time and the air starts to cool, but then it stops and the unit blows air from the outside it seems.
I changed the 40A fuse just in case. Also, the AC pressure seems good.
But the compressor responds to cooling requests from the cabinet rather randonly; it mostly doesn't come on at all even though its quite hot in the car's cabin and the cooling settings is set to the lowest I can request in the dash controls.

Thanks for your suggestions.

 

When the compressor isn't running, the air from the outside isn't cooled or the air inside your car if you have the recirculation turned on is not cooled.

When the a/c compressor is commanded on, both cooling fans on the radiator should turn on. To get some direction on the root cause, watch the a/c compressor clutch plate. The plate will spin with the pulley if the a/c compressor is commanded on.

There is also a way to test for HVAC codes. See the common diy thread in the gen tech help section on how to read HVAC codes. Let us know of any codes you get.

Open the hood and watch the compressor clutch and the two fans. Let us know if the clutch is spinning, or turning on/off. Let us know how the fans operate when the compressor clutch is spinning and/or not spinning.

Please do not add R-134a to your system using one of those cans with pressure gauges. The charge may not be the problem and you could create a bigger problem.

Also, how did you test the system pressure? A manifold is necessary, where you read the high and low pressures.

Has your car ever had a/c work, where the system was recharged?

 

Thanks for the reply.
Here is what I found:

The a/c compressor clutch plate and the two fans comes on and off together. However, they stop at seemingly random points even when the air in the cabin is not cooled. In general, they blow cool air only for short periods then stop and the air after that is uncooled. Its seems when the air is uncooled, the compressor and the fans are not running, even through in the cabin the request is to continue to cool.

I "tested" the pressure system by attaching a can of the R-134a and observing the pressure guage there. It was Red, which meant bad and not to go further. And I didn't.

I guess I have to try to read HVAC codes.

Thank you.

 

Reading the HVAC codes from the car is also a good idea, because the compressor/fan controls are working.

Next step would be to test the low and high pressure lines with a manifold. Parts stores have these as loaner tools. You'll need to read the pressure when the compressor is running to get an idea of how the system is working. Watch some youtube videos on how to setup and use the gauges.

 

Ok. I just purchased a Manifold gauge and will readup on how to use it.

Should get it on Friday.

 

So faced a more fundamental issue:

The AC will not come-on on command. It comes on sometimes and seems to go off shortly after - it mostly stay off. This evening it would not come on at all. And
by this I mean the AC clutch plate as well as the two fans aren't spinning even though I have the AC on the dash ON and at maximum.
Today was a bit cool...but even so my 2015 Honda's AC came-on on command, the 2003 won't budge at all.

What do you think?

Also, I do have the manifold gauge to measure my pressure.

Thanks.

 

Try reading the hvac trouble codes to see if something in the system is malfunctioning like an evaporator temp senor, pressure switch etc. It is pretty simple to do and may give you a direction on what is happening.

I'll have to dig into the wiring to see if you have something you can easily test with a volt meter or test light to get a direction.

 

Do you read auto HVAC does with a ODB2 meter?

 

Open the common diy thread in the gen tech help section, There is a link in there on how to read HVAC codes, Just hitting some buttons on the hvac controls inside the car.

 

So went through some of that section. However, they key to interpret the results were not clear to me.
I got a DTC on the leftermost 8 at the upper right hand vertical side. See below at A
I am not sure what that means!

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