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Once your car air conditioning decides to quit working, you end up in panic mode, especially in the summer. After all, who wants to arrive at work drenched in sweat? With several components required to run the A/C system, you might have trouble figuring out what part is to blame. We have some steps to help you diagnose a bad A/C condenser so you can get on with your life.

Can You Drive with a Failed A/C Condenser?

It’s not comfortable to drive in warm weather without a working condenser, but this won’t harm your vehicle. Still, you don’t want to just ignore the problem.

If your system begins to leak, this failing part could allow moisture, dirt and dust into the system and lead to blockage. This might require additional repairs. That’s why you must perform diagnostics at the first sign of trouble.

Causes of Condenser Failure

Condenser failure occurs for two main reasons. The first probable cause is that the condenser began leaking. There are seals on the part that leak with normal wear and tear. The condenser tubes can’t be replaced, so you need a new condenser if it cracks or breaks. It’s also possible for the leakage to occur when physical damage stems from road debris or rocks. Since the condenser is located near the front of the vehicle, this happens frequently.

, How to Diagnose a Bad A/C Condenser
It’s not comfortable to drive in warm weather without a working condenser, but this won’t harm your vehicle. Still, you don’t want to just ignore the problem.

The second cause is that there is a blockage caused by metallic debris. This blocks the required circulation from happening. Typically, this results from a defective or failing compressor that breaks apart. As the internal parts disperse, the metallic debris ends up throughout the entire system. In this situation, you might need more than a condenser, but also the tubes, receiver dryer and compressor.

Troubleshooting a Leaky A/C Condenser

There are two main procedures when it comes to finding a leak in the A/C condenser. One is used by us mechanics at the dealership and the other method works well at home. Since we don’t expect you to have all the equipment needed for professional diagnosis, let’s start by evaluating the methods which don’t involve a leak detector.

No Leak Detector Required

Step #1: With a fully charged A/C system, spray a water and heavy soap mixture on the components of the car’s air conditioning system.

Step #2: Watch for leaks to appear. You won’t be able to try this method with evaporator or compressor front seal leaks.

It’s also possible to purchase Freon dyes that utilize a black light. Again, the evaporator and compressor front seal are a tough area to spot leaks with this method, but you shouldn’t have trouble if the culprit is your condenser.

, How to Diagnose a Bad A/C Condenser
To detect a leak, you can spray a water and heavy soap mixture on the components of the car’s air conditioning system.

If a small leak is present, you may be able to repair it with a Stop Leak product. If you notice visible holes or clear damage to the condenser, you have no option but to replace it. While I realize this is a pain, it’s the only way to ensure that your air conditioning works properly.

What if There is No Leak?

If you finish your leak testing without any incident, your next step is to look for a clogged condenser. Checking your pressures is the next logical place to start. With a clogged condenser, you will notice higher pressures even though you have the right amount of refrigerant in the system. These higher pressures are noticed on both the high and low side.

Condensers are subject to clogs because of the leftover particles in the refrigerant. As the condenser converts refrigerant, residue tends to remain at the bottom. It eventually turns into a sticky paste that hinders conversion.

Leak Detector Required

If your system doesn’t show any immediate signs of leakage, then you want to purchase a leak detector.

Step #1: Make sure the system is full of Freon. You also want the engine to be turned off. Ideally, there should be no breeze or wind. Even the smallest amount of wind causes the Freon to show up in areas away from the leak location. This might lead to a false reading. Consider checking your vehicle in a garage to be certain no outside factors affect your readings.

, How to Diagnose a Bad A/C Condenser
If you don’t receive any alerts to a leak using a leak detector, adjust the sensitivity settings and scan again. Continue to move up in sensitivity as you scan.

Step #2: Turn on your detector and adjust it to the lowest sensitivity setting. You will test the O rings first since this is a common place for leaks to occur. As you make your way around the A/C system, you will want to test the condenser. It often gets hit with debris and small rocks which can cause a leak. As you examine the condenser, don’t forget to look at the hose connections as well.

Step #3: Listen for a rapid beep as a sign. These signals indicate a leak. If you don’t receive any alerts to a leak, you want to adjust the sensitivity settings and scan again. Continue to move up in sensitivity as you scan.

The biggest sign that you have a clog other than the pressure check is a foul smelling odor during air circulation. When a clog is apparent, you have the option to attempt a flush or replace the condenser. At the dealerships, we’ve had many customers force us into a flush. While it might look like an easy solution, be forewarned, you might end up with bigger problems.

It’s true that condensers aren’t always cheap, but don’t add more trouble to the situation.

What if the Condenser Isn’t the Problem?

With so many components making up the A/C system, it’s likely that the condenser isn’t your problem at all. Many times, bad evaporators, leaks in the lines or a lack of refrigerant can cause the same symptoms. When in doubt, seek the help of a professional for further guidance.

Get Back in the Cold Again

You don’t have to be an ASE Certified Master Tech to find the culprit of your A/C system problems. Get your tools gathered and start the hunt. Once you’ve determined the problem, it’s time to move on to getting the repair done.

Products Mentioned in this Guide

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic.

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My ’07 Honda Civic AC works for 20 minutes and then blows warm air. I bought a can of refrigerant but the guage indicated the level was adequate…..was suggested the clutch was bad…How does one know and is it best to replace the entire compressor?

Hello Terry,

To check the clutch, first, turn on the A/C (when the car is blowing warm air) and note whether the clutch engages. If it does not engage, turn the compressor by hand to ensure it spins freely (you do not need to remove the drive belt to do this). Next, check the compressor control circuit to make sure power is getting to the clutch. A circuit issue, such as a faulty clutch relay, can prevent the clutch from engaging. You’ll also want to check the A/C thermal protector, which can prevent the compressor from operating as it should. If the compressor itself turns freely and the control circuit checks out, the clutch is likely at fault.

Sometimes, the clutch gap is beyond specification, so you might want to check that before replacing the clutch or compressor. If the gap exceeds the manufacturer’s specifications, you can use shims to dial it in, rather than replacing the clutch or compressor.

I recommend you consult a repair manual or repair database if you’re going to troubleshoot the problem yourself. Check out this article for more information:

Finally, there’s no need to replace the entire compressor if you find that only the clutch is bad. But replacing the clutch is more difficult than replacing the entire compressor. The good news is: Because you’re not opening up the system, there’s no need to recover, evacuate, and recharge the A/C refrigerant when you just replace the clutch.

ceasar ricks

where is the evaporator located 1994 mercury grand marquis

Hi Ceasar,

It’s located in the evaporator core case (plenum) behind/underneath the dashboard.


2017 Silverado LTZ – heavy rain at night and slid off the road and took out a tree And then ran over the tree. Damaged truck from the front bumper to the back passenger door. And then found my AC quit working. The collision center did a evac and recharge and filled it with Freon. Insurance covered. 2 days later AC back blowing hot. Collision center recommended i take to a true mechanic. Took to dealership to simply have light shined in grill and told condenser is bad and no way wreck could have caused it. AC worked fine until I had wreck.
How do I know for sure it’s the condenser.
How do I know the wreck didn’t attribute to the not working. No dye test done. Just a simple light shined in the grill.
Any help is appreciated. Too coincidental.

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