2020 Jeep Grand Cherokee AC Not Working – Diagnose And Fix

By • March 2, 2026 • Jeep

There’s nothing quite like the open road, the wind in your hair, and the roar of a powerful engine. But when the summer heat hits, or you’re stuck in traffic, a broken air conditioning system can quickly turn an adventure into an ordeal. For owners of a 2020 Jeep Grand Cherokee, an AC that’s not working properly can be particularly frustrating, especially when you’re counting on that comfortable cabin for long hauls or dusty trail rides.

You’ve invested in a capable vehicle, and you expect its comfort systems to keep up. When your 2020 jeep grand cherokee ac not working, it’s more than just an inconvenience; it can impact your focus and enjoyment, whether you’re commuting or heading to a remote campsite. Don’t sweat it just yet! This expert guide from FatBoysOffroad will walk you through the most common reasons your Grand Cherokee’s AC might be failing and empower you with practical, DIY diagnostic steps and solutions. We’ll help you pinpoint the problem and get that cool air flowing again, saving you time, money, and a lot of discomfort.

We promise to provide clear, actionable advice, explaining complex issues in simple terms. By the end of this article, you’ll have a solid understanding of your Jeep’s AC system and the confidence to tackle many common repairs yourself, or at least know exactly what to tell your mechanic.

Common Reasons Your 2020 Jeep Grand Cherokee AC Not Working

When your climate control system starts blowing warm air, or nothing at all, it can stem from several different issues. Understanding the most frequent culprits is the first step in diagnosing why your 2020 jeep grand cherokee ac not working.

We’ll break down the usual suspects, from simple fixes to more complex system failures.

Low Refrigerant Levels or Leaks

The most common reason for a failing AC is often a lack of refrigerant, also known as Freon. This vital fluid circulates through your AC system, absorbing heat from the cabin and releasing it outside.

Refrigerant doesn’t get “used up”; if it’s low, you likely have a leak somewhere in the system.

  • Identifying a Leak: Leaks can occur in hoses, O-rings, the condenser, evaporator, or compressor seals. A professional can use UV dye or an electronic leak detector to find the exact source.
  • Recharge Considerations: While an AC recharge kit might seem like a quick fix, it only masks the problem if there’s a leak. The refrigerant will eventually escape again, potentially pulling moisture and contaminants into the system.

Electrical System Failures: Fuses, Relays, and Wiring

Modern AC systems are heavily reliant on electrical components. A simple blown fuse or a faulty relay can completely shut down your cooling.

These are often the easiest and cheapest fixes.

  • Checking Fuses: Your Jeep Grand Cherokee has several fuses related to the AC system, including for the blower motor, compressor clutch, and control module. Consult your owner’s manual for the exact fuse box locations (usually under the hood and/or inside the cabin).
  • Inspecting Relays: The AC compressor clutch relay is a common point of failure. You can often swap it with a known good, identical relay from another non-critical system (like the horn) to test if it’s the culprit.
  • Wiring Issues: Corrosion or damage to wiring harnesses can interrupt power. Visually inspect accessible wiring, especially near the compressor and blower motor, for any signs of fraying or burning.

Compressor Clutch or Compressor Failure

The AC compressor is the heart of your system. It pressurizes the refrigerant, getting it ready to cool your cabin.

If the compressor or its clutch isn’t engaging, you won’t get any cold air.

  • Compressor Clutch Check: With the engine running and AC on high, look at the front of the compressor. The outer part of the clutch should be spinning. If it’s not, power isn’t reaching it, or the clutch itself is seized.
  • Compressor Health: A failing compressor might make grinding noises or simply refuse to engage. This is a more complex and costly repair, often requiring specialized tools and vacuum pumps for proper replacement.
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Blower Motor or Resistor Problems

Even if your AC system is making cold air, you won’t feel it if the blower motor isn’t pushing that air into the cabin.

A faulty blower motor or its resistor can lead to no air, or air only at certain speeds.

  • No Air Movement: If you turn on the AC and hear nothing from the vents, suspect the blower motor or its fuse/relay.
  • Variable Fan Speeds Only: If the fan only works on high speed, or only on some speeds, the blower motor resistor is likely faulty. This component regulates the voltage to the blower motor to control fan speed.

Blend Door Actuator Issues

Your Jeep’s climate control uses blend door actuators to direct airflow and mix hot and cold air to achieve your desired temperature. If one of these fails, your system might blow only hot air, even if the AC is technically working.

These small motors are often located behind the dashboard.

  • Symptoms: Common signs include clicking or whirring noises from behind the dash, or the AC blowing warm air on one side of the vehicle and cold on the other (dual-zone climate control).
  • Diagnosis: While diagnosing these can be tricky, sometimes a simple calibration sequence (check your owner’s manual or a Jeep forum) can reset them. Otherwise, replacement often requires significant dashboard disassembly.

DIY Diagnostic Steps for Your 2020 Jeep Grand Cherokee AC Not Working

Before you rush to a professional, there are several straightforward checks you can perform in your driveway. These steps can help you identify obvious issues or narrow down the problem, saving you diagnostic fees.

Always prioritize safety when working on your vehicle.

Step 1: Check Your Fuses and Relays

This is the simplest starting point and can resolve many issues where the 2020 jeep grand cherokee ac not working at all.

Always disconnect the battery before working with fuses or relays to prevent electrical shorts.

  1. Locate Fuse Boxes: Refer to your owner’s manual for the locations of your Jeep’s fuse boxes. Typically, there’s one under the hood (Power Distribution Center) and one inside the cabin (Integrated Power Module or similar).
  2. Identify AC Fuses: Find the fuses specifically labeled for the “AC clutch,” “blower motor,” “HVAC,” or “climate control.”
  3. Inspect Fuses: Pull each relevant fuse using a fuse puller. Hold it up to the light; if the wire inside is broken, the fuse is blown. Replace it with a new fuse of the exact same amperage.
  4. Test Relays: Identify the AC compressor clutch relay. If you have an identical relay for a non-essential circuit (like the horn or fog lights), swap them. If the AC now works, you’ve found your culprit.

Step 2: Listen to the Compressor Clutch

The compressor clutch makes an audible click when it engages. This indicates that it’s receiving power and attempting to compress refrigerant.

No click suggests an electrical issue or a seized clutch.

  1. Start Engine: Ensure the engine is running and in park.
  2. Turn AC On: Set your climate control to MAX AC and the fan speed to high.
  3. Observe Compressor: Locate the AC compressor, usually on the lower front of the engine, driven by the serpentine belt.
  4. Listen for the Click: You should hear an audible “click” as the clutch engages, and the front plate of the compressor should start spinning with the pulley. If you hear no click or the clutch doesn’t spin, there’s a problem.

Step 3: Check Blower Motor Operation

If you have cold air at the vents but no airflow, or only airflow at certain speeds, the blower motor or resistor is likely at fault.

This check is quick and easy.

  1. Turn On Fan: With the engine running, turn your climate control fan speed through all its settings, from low to high.
  2. Listen and Feel: Listen for the blower motor operating and feel for air coming from the vents.
  3. Diagnose:
    • If there’s no air at any speed, check the blower motor fuse and relay first. Then suspect the blower motor itself.
    • If air only works on high speed, or only some speeds, the blower motor resistor is almost certainly bad.
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Step 4: Inspect the Cabin Air Filter

A severely clogged cabin air filter can restrict airflow, making your AC feel weak or ineffective. It’s often overlooked but can cause significant discomfort.

This is a quick and cheap maintenance item.

  1. Locate Filter: On a 2020 Grand Cherokee, the cabin air filter is typically located behind the glove box. Consult your owner’s manual for exact instructions.
  2. Remove and Inspect: Carefully remove the filter. If it’s dirty, dark, or packed with leaves and debris, it needs to be replaced.
  3. Replace if Needed: Install a new cabin air filter, ensuring it’s oriented correctly (airflow arrow pointing towards the cabin).

Step 5: Check Refrigerant Pressure (Requires Tools)

This step requires an AC manifold gauge set, which can be purchased at most auto parts stores. This tool measures the high and low side pressures of your refrigerant system.

Incorrect pressures are a strong indicator of low refrigerant or a system blockage.

  1. Connect Gauges: With the engine running and AC on MAX, connect the blue low-side hose to the low-pressure service port (usually on the larger diameter line) and the red high-side hose to the high-pressure service port (smaller diameter line).
  2. Read Pressures: Compare your readings to the manufacturer’s specifications (often found on a sticker under the hood or in a service manual). Low pressure on both sides usually indicates low refrigerant. High pressure on both sides can indicate an overcharge or a system blockage.
  3. Safety First: Refrigerant is under pressure. Wear eye protection and gloves. If you’re unsure, this is a good point to consult a professional.

Advanced Troubleshooting and When to Seek Professional Help

While many AC issues can be diagnosed by a diligent DIYer, some problems require specialized tools, knowledge, and certifications. Knowing when to call in the pros is crucial for safety and preventing further damage.

Don’t hesitate to seek expert advice if you’re out of your comfort zone.

Diagnosing Complex Electrical Gremlins

If fuses and relays are good, but the compressor still isn’t engaging, you might have a deeper electrical issue. This could involve the pressure switches, temperature sensors, or the HVAC control module itself.

These components require more advanced diagnostic tools, like a multimeter and potentially a scan tool.

  • Pressure Switches: Your AC system has high and low-pressure switches that prevent the compressor from running if pressures are too low (due to a leak) or too high (due to a blockage or overcharge). A faulty switch can prevent the system from engaging.
  • HVAC Control Module: The central brain of your climate control system can fail. This often presents with erratic behavior, like controls not responding or incorrect temperatures.
  • Professional Scan Tools: A mechanic’s scan tool can read fault codes from the HVAC module, pinpointing specific sensor or actuator failures.

Dealing with Refrigerant Leaks and System Contamination

If your refrigerant is low, there’s a leak. While some minor leaks can be temporarily sealed with stop-leak products (which we generally advise against for long-term health), a proper repair involves finding and fixing the leak.

Refrigerant is a controlled substance, and proper handling is essential.

  • Leak Detection: Professionals use UV dye and specialized sniffers to accurately locate leaks.
  • Evacuation and Recharge: After a leak repair, the system must be properly evacuated (vacuumed) to remove all air and moisture before being recharged with the correct amount of refrigerant. Moisture is highly detrimental to AC system components.
  • Component Replacement: If a major component like the condenser or evaporator is leaking, replacement is necessary. This can be labor-intensive and costly.

Compressor or Major Component Replacement

A failed compressor, condenser, or evaporator is a significant repair. These jobs typically require evacuating the system, removing and replacing the faulty component, and then re-evacuating and recharging the system.

Don’t attempt this without the right tools and knowledge.

  • Specialized Tools: You’ll need a vacuum pump, manifold gauges, and potentially a flush kit to ensure no debris from a failed compressor contaminates the new one.
  • Safety Risks: Working with pressurized refrigerant and heavy components can be dangerous. Leave these complex repairs to certified AC technicians.
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Maintaining Your Jeep Grand Cherokee’s AC System

Preventative maintenance is key to avoiding future AC headaches. A little care goes a long way in ensuring your climate control system remains robust, especially for off-roaders who push their vehicles harder.

Regular checks can extend the life of your AC components.

  • Regular Cabin Air Filter Replacement: Change your cabin air filter at least once a year, or more frequently if you drive in dusty conditions (like off-road trails). A clean filter improves airflow and AC efficiency.
  • Run Your AC Regularly: Even in winter, run your AC for 10-15 minutes once a month. This lubricates the compressor seals and prevents them from drying out, which can lead to leaks.
  • Keep Condenser Clean: The condenser, located in front of your radiator, needs good airflow. Regularly clear leaves, bugs, and debris from its fins using a soft brush or compressed air. Be gentle to avoid bending the delicate fins.
  • Monitor for Strange Noises: Pay attention to any new or unusual sounds when your AC is running, such as grinding, squealing, or clicking. These can be early warnings of component failure.

Frequently Asked Questions About 2020 Jeep Grand Cherokee AC Not Working

Why is my 2020 Jeep Grand Cherokee AC blowing warm air but the fan is working?

If your fan is working but the air isn’t cold, the most common causes are low refrigerant (due to a leak), a faulty AC compressor clutch not engaging, a bad AC compressor, or an issue with the blend door actuator stuck on hot. Start by checking the compressor clutch engagement and then consider refrigerant levels.

Can a simple fuse cause my 2020 Jeep Grand Cherokee AC to stop working completely?

Absolutely. A blown fuse for the AC compressor clutch or the blower motor can completely disable your AC system. Always check the relevant fuses in your under-hood and in-cabin fuse boxes first, as this is a quick and inexpensive fix.

How often should I recharge my Jeep Grand Cherokee’s AC system?

Ideally, never. Your AC system is a sealed unit, and if it’s losing refrigerant, there’s a leak that needs to be repaired. Only recharge the system after a leak has been fixed and the system has been properly evacuated to remove air and moisture.

Where is the AC compressor clutch relay located on a 2020 Grand Cherokee?

The AC compressor clutch relay is typically located in the Power Distribution Center (PDC) under the hood. Consult your owner’s manual or the diagram on the inside of the PDC cover for the exact location. It’s often labeled “AC Clutch” or “HVAC RLY.”

Is it safe to drive my 2020 Jeep Grand Cherokee if the AC compressor is seized?

If your AC compressor is seized, it can put excessive strain on your engine’s serpentine belt, potentially causing it to break. A broken serpentine belt can lead to loss of power steering, alternator function, and water pump operation. It’s best to address a seized compressor promptly, either by replacing it or bypassing it if possible (though bypassing isn’t always feasible on all engines).

Conclusion

Dealing with a 2020 jeep grand cherokee ac not working can be a real pain, especially when you’re counting on your rig for comfort on those long drives or dusty trails. But by following the diagnostic steps outlined in this guide, you’re well-equipped to identify many common problems yourself.

Remember, safety is paramount. Always wear appropriate personal protective equipment, disconnect the battery when working with electrical components, and never work with a hot engine. While many fixes are DIY-friendly, don’t hesitate to seek professional help for complex issues, especially those involving refrigerant handling.

With a little patience and the right approach, you can get your Jeep’s AC blowing cold again, ensuring your adventures remain comfortable and enjoyable. Stay cool, stay safe, and keep those wheels turning!

Thomas Corle
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