Recharging the refrigerant on your vehicle's air conditioning system requires that you connect your R-134A recharge kit to the low side fitting near the compressor. With the air conditioning running, the refrigerant from the recharge kit is sucked into the compressor's storage system. However, if the compressor is not turning on, then you must troubleshoot the compressor itself before recharging the air conditioning. If the compressor cannot be turned on, then you must take the vehicle to a professional mechanic to have the system purged, replace the compressor and recharge the refrigerant.
Things You'll Need
- OBD II scanner
- Jumper wire
- R-134A recharge kit
Hook an OBD II scanner to your OBD II terminal on your car, which is typically located to the lower left part of the steering column behind a small panel. Turn on the OBD II scanner and turn on the car's ignition to the accessories position. Retrieve the OBD II code for any sensors or circuits that have malfunctioned or failed. If the air conditioning pressure sensor or switch comes up on the OBD II code, then you may need to replace it before the compressor will turn itself on. If your scanner does not tell you the interpretation of the code, you will need to look it up on websites such as OBD II Code or AutoZone.
Turn on your engine and air conditioning and listen for sounds such as metallic bearings clicking or loud knocking noises coming from the compressor. If you are hearing any of these sounds or have recently heard them, then your compressor is either lacking lubricant and refrigerant or has air that needs to be purged by a mechanic. If the compressor is low on lubricant and refrigerant, then you may be able to re-engage the clutch by using a jumper wire.
Locate the single wire connector near the front side of the air conditioning compressor. Unplug the single wire connector and hook it up to the jumper wire. Connect a jumper wire to the positive terminal of your car battery. Turn on the air conditioning system to full blast inside your car, which should cause the clutch to engage on the compressor.
Attach the recharge kit to the low side fitting, which is marked with an upper case "L," and turn on the recharge kit's valve. The low-side fitting is located between the compressor and the accumulator. Continue to allow the kit to recharge the vehicle's refrigerant until it is blowing out cold air again, measuring between 40 and 50 degrees Fahrenheit on a thermometer installed on your dashboard.
Watch the low pressure gauge on your recharge kit if it is included. The low pressure gauge should read between 25 and 40 psi (pounds per square inch) when the refrigerant is fully charged. To avoid the risk of overcharging your air conditioning system, which can cause expensive leaks, shut off the recharge kit when the low pressure reading reaches 25 psi.
- Photo Credit Jupiterimages/Photos.com/Getty Images
Why Do Auto AC Compressors Turn Off?
An automotive air conditioning system is powered by a compressor. This compressor will turn off and on as needed to operate the...
How to Use Electrical Jumper Wires
The term "jumper wire" simply refers to a conducting wire that establishes an electrical connection between two points in a circuit. You...
How to Recharge an Auto AC
Recharging an auto air conditioning system is a fairly simple task. However, it does require some understanding of the system. The common...
How to Test an AC Clutch Coil
The A/C compressor is the heart of the system, and without a good compressor, the unit will not function. The compressor is...
How to Charge Auto AC With Freon
Freon is what keeps your vehicle's air conditioning unit producing cold air. Over time, though, the freon can be depleted, leaving you...
How to Connect Wiring to an AC Compressor
While wiring a compressor, there are a number of things to consider for a proper electrical hook up. A main concern is...
My Air Conditioner Compressor Is Not Kicking On
An air conditioner's compressor controls the distribution of cold air throughout the house. When the compressor is not coming on, your air...
The AC Compressor in My Nissan Frontier Won't Turn On
The Nissan Frontier, like many vehicles, sometimes suffers from air conditioning problems. If the compressor of the air conditioning won't turn on,...
The AC Compressor in My '98 Cadillac DeVille Won't Turn On
There are many potential reasons why an air conditioner compressor in a Cadillac DeVille won't engage. Some problems, for instance, may be...