Location Low Side A/c Charging Port

[johnabby]

Could someone advise the location of the low side A/C charging port on 2003 GMC 1500HD? A/C seems less cold, and the compressor On cycle seems to be longer than other vehicles. My thought was to top up the refrigerant.

[Jsdirt]

If your low on refrigerant, the cycles will be short & rapid. You'll hear the compressor constantly engaging/disengaging.

 

Things to check are debris between or in front of the condenser & radiator, bad fan clutch, or a blend door problem.

[johnabby]

If your low on refrigerant, the cycles will be short & rapid. You'll hear the compressor constantly engaging/disengaging.

 

Things to check are debris between or in front of the condenser & radiator, bad fan clutch, or a blend door problem.

Smitty, Thanks for the tip. I was wondering about the fan clutch. The truck blows much colder @ highway speed and warm in traffic. Condensor and radiator verified clean and flushed with garden hoes. Is there any "test" for bad viscous fan clutch?

[txab]

If your low on refrigerant, the cycles will be short & rapid. You'll hear the compressor constantly engaging/disengaging.

 

Things to check are debris between or in front of the condenser & radiator, bad fan clutch, or a blend door problem.

Smitty, Thanks for the tip. I was wondering about the fan clutch. The truck blows much colder @ highway speed and warm in traffic. Condensor and radiator verified clean and flushed with garden hoes. Is there any "test" for bad viscous fan clutch?

 

 

Do you ever hear the fan lock-up and roar like it did when new. It's usually hard to tell visually when a clutch is getting weak. With extreme failure you can literally grab hold the blade still while the engine is running. (Not recommending to do this.) If you've got 70k + miles, I'd replace it for good measure. They do weaken and wear out. AC performance is where it shows first.

 

Have you had your system pressures checked with a good set of guages?

[Draenor]

If your low on refrigerant, the cycles will be short & rapid. You'll hear the compressor constantly engaging/disengaging.

 

Things to check are debris between or in front of the condenser & radiator, bad fan clutch, or a blend door problem.

Smitty, Thanks for the tip. I was wondering about the fan clutch. The truck blows much colder @ highway speed and warm in traffic. Condensor and radiator verified clean and flushed with garden hoes. Is there any "test" for bad viscous fan clutch?

 

 

Do you ever hear the fan lock-up and roar like it did when new. It's usually hard to tell visually when a clutch is getting weak. They do weaken and wear out. AC performance is where it shows first.

 

Have you had your system pressures checked with a good set of guages?

 

+1

Sounds like a failing fan clutch. Do you have a thermometer you can stick in the vent?

[bill190]

The low side charging port is usually near the metal can (accumulator) near the fire wall and would be cool to the touch with the A/C running.

[ZZ327]

If youre using the guage you can buy from the auto parts store. They ONLY fit the low side!