How to charge AC on any Cadillac   ATS, CTS, XTS, CT6, XT5, Escalade, SRX, DTS, STS, BLS, XLR

How to charge AC on any Cadillac

Last Updated on Thursday Apr 05, 2018

In this guide, you will find instructions on how to charge Air Conditioner (A/C) system with refrigerant (R134a freon) on any Cadillac. If your A/C is blowing hot air, there is a good chance that the system is low on freon. Charging Cadillac A/C system with refrigerant is easy and takes about 15 minutes. These instructions will help the owners of Cadillac ATS, CTS, XTS, CT6, XT5, Escalade, SRX, DTS, STS, BLS, XLR vehicles, and other models. The only difference between various Cadillac models is that the A/C charging port is located in different places in the engine bay. 


One of the most common symptoms that your Cadillac is low on refrigerant is the A/C blowing hot air even when the temperature is set to cold settings. 

What you will need


Before you start charging your Cadillac A/C system make sure that other components are in good working condition. Cadillac A/C may stop working if it is low on freon but also due to other problems such as A/C compressor not working, bad A/C clutch, bad temperature sensor, major freon leak etc. 

Step 1: Park Vehicle

Park your Cadillac in a safe area. Turn off the engine.

Step 2: Open hood

To add freon to your Cadillac you need to locate the A/C low pressure charging port in the engine bay. Pull the hood release under the dashboard until you hear your Cadillac hood pop open. 

Step 3: Locate A/C port

location of a/c low pressure port on Cadillac  3rd

Next, locate the low-pressure port. Label 11 in this picture shows where the A/C charging port is on a Cadillac. Note that there also is a high-pressure line as well. The A/C charging kit connector will not fit on the port for the high-pressure line.

Step 4: Remove cap

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Carefully remove the cap from the low-pressure port by twisting it counterclockwise.

Step 5: Connect recharge kit

 Cadillac  ac recharge diy video allmo allyr

Connect your A/C charging kit to the A/C charging port. You are almost ready to add freon to your vehicle A/C system. Don't start adding refrigerant to your Cadillac A/C system yet.

Step 6: Start Engine

how to charge the ac on Cadillac

Start the engine of your car and allow your Cadillac to idle.

Step 7: Turn A/C on

Next turn A/C on and set it to the max cold setting. Set the blowing fan to maximum speed. Now you are ready to start adding refrigerant to your Cadillac air conditioner system.

Step 8: Charge

Add refrigerant as directed by the manufacturer of the A/C recharge kit you are using. You will need to press and hold the trigger until your Cadillac A/C is fully charged. This process can take several minutes. When the a/c system is low on freon, the compressor may not be engaged at first. As you add refrigerant you should hear the compressor kick in.  As you charge the system stop pressing the trigger every couple of minutes to obtain a pressure reading.  Continue adding refrigerant until your gauge reaches in the charged range. Do not allow the system to overcharge or be in the overfilled range.

 Important Notes

  • Keep the can upright and rotate it between 1 and 2 o’clock as you charge the a/c. 
  • If your vehicle uses a clutchless compressor also known as variable displacement compressor, the clutch will always look as being engaged. 
  • Do not overfill your system with freon. 
  • Do not turn the can upside when you charge the A/C. It can introduce liquid refrigerant to a/c system which can cause the locking up the a/c compressor.
  • Always follow the instructions that are provided with your specific kit.
  • It is normal for the gauge to point in the high range when the engine is turned off.

Frequently Asked Questions

The most common problem is vent actuator in vehicles with dual zone A/C. They can get stuck in one position and do not switch when you change the temperature. In vehicles that use duo-valves they can also get stuck in which case half of the car blows hot air and the other blows cold air.

The cooling fan for the condenser may not be working.

The blower fan may be defective.

AC may be low on freon. Also check low-pressure switch. If defective it can prevent the compressor from operating.


Posted by Jennifer on Apr 5, 2018 @ 21:48 pm