If your Cosori TurboBlaze air fryer is flashing E01, E02, E21, E22, or E04 on its display, you’re dealing with a specific hardware or electrical fault. These codes are definitive error messages that tell you exactly what’s wrong. The good news is that each one has a clear path to resolution, and for most of them, the fix is straightforward and doesn’t require any technical skill. We’ll break down what each code means, why it happens, and the exact steps you need to take to get your air fryer working again.
Quick Answer: Error E04 means you’ve plugged the 120V-only air fryer into a 220–240V outlet; immediately unplug it and only use a standard 120V household outlet. Errors E01/E21 and E02/E22 indicate a faulty temperature sensor; do not attempt to repair it yourself—you must contact Cosori Customer Support for service or a replacement.
Understanding the Error Codes
These error codes are your air fryer’s diagnostic system. When it detects a problem it can’t compensate for, it shuts down critical functions like heating and displays a specific code to prevent damage and point you toward the solution. They fall into two distinct categories: a power supply issue (E04) and internal sensor faults (E01/E21, E02/E22).
E01/E21: Open Circuit in Temperature Monitor
When the display shows E01 or E21, it means the air fryer’s internal temperature monitoring system has an open circuit. The wire or connection to the temperature sensor has broken or come disconnected. This break means the control board can no longer receive a temperature reading from inside the cooking chamber. Without this critical data, the air fryer cannot safely regulate heat, so it stops the heating process entirely and shows you the code. This is a fault that requires professional attention.
E02/E22: Short Circuit in Temperature Monitor
Error E02 or E22 indicates the opposite problem: a short circuit in the temperature monitor. Here, the wiring or the sensor itself has failed in a way that creates an unintended electrical path. This typically sends an incorrect, often maximum, signal to the control board, making it think the temperature is dangerously high when it may not be. To prevent a potential overheating scenario, the air fryer immediately cuts power to the heater and displays the error code. Like E01, this is an internal electrical fault you cannot fix at home.
E04: Wrong Voltage (120V Only)
Error E04 is fundamentally different and is strictly related to your power source. The Cosori TurboBlaze 6 Qt air fryer is designed to operate only on 120V, 60Hz AC power, the standard for household outlets in the United States and Canada. If you plug it into a 220–240V outlet, common in many other regions or sometimes found in homes for dryers, the internal components receive double the intended voltage. The circuitry detects this over-voltage condition, prevents operation, and shows E04 to alert you before any damage occurs.
How to Fix Error E04 (Wrong Voltage)
Fixing an E04 error is about correcting your setup. There is nothing wrong with your air fryer; it’s protecting itself. Follow these steps in order.
Unplug Immediately
As soon as you see the E04 code, press the power button to turn the unit off. Then, go directly to the wall outlet or power strip and unplug the air fryer. This removes the incorrect voltage and is the only immediate action you need to take. Leaving it plugged into a 240V outlet, even if it’s off, can stress the internal components.
Check Your Outlet Type
Identify why it was plugged into a high-voltage outlet. Are you traveling or living outside North America? Standard outlet voltages differ by country. Alternatively, are you in a garage, laundry room, or workshop where a 240V outlet for a heavy-duty appliance might be present? These outlets often have differently shaped sockets. If you’re unsure, a simple outlet voltage tester can confirm the voltage.
Only Use 120V Outlets
This is the non-negotiable rule. You must plug the air fryer into a standard 120V household outlet. Do not use a voltage converter or transformer; these are not recommended for high-wattage heating appliances like air fryers and can pose a serious fire hazard. Using a converter voids the warranty and is unsafe. Once plugged into the correct outlet, the E04 code should clear, and you can resume normal use. If the code persists after being plugged into a confirmed 120V outlet, then a different internal fault may have occurred, and you should contact support.
For E01/E21 and E02/E22: Contact Support
Unlike the E04 error, codes E01, E21, E02, and E22 point to an internal failure. The solution is to contact Customer Support. Attempting a DIY repair is dangerous, will void your warranty, and could lead to electric shock or fire.
Don’t Try to Repair It Yourself
The air fryer contains high-voltage components and a complex heating system. Disassembling the unit to access the temperature sensor or its wiring exposes you to live electrical parts even when unplugged, due to stored charge in capacitors. Furthermore, using the appliance with a faulty temperature monitor is a severe safety risk, as it cannot accurately control cooking temperature. Professional technicians have the correct tools, parts, and training to diagnose and repair these faults safely.
Have Your Order ID Ready
To expedite your support request, locate your proof of purchase. This is typically the order confirmation email, receipt, or the order number from the website where you bought it. Having this information ready allows Cosori’s support team to verify your purchase date, determine if your unit is under warranty, and process a replacement or repair order much faster. Be prepared to describe the error code displayed and any circumstances leading up to it.
| Problem (Error Code) | Quick Fix | Expected Result |
|---|---|---|
| E04 on display | Unplug from outlet. Plug into a standard 120V household outlet only. | Error clears. Air fryer operates normally on correct voltage. |
| E01 or E21 on display | Stop use. Contact Cosori Customer Support for service. | Support will guide you through warranty repair or replacement process. |
| E02 or E22 on display | Stop use. Contact Cosori Customer Support for service. | Support will guide you through warranty repair or replacement process. |
Frequently Asked Questions
Can I use a voltage converter to fix the Cosori E04 error if I live overseas?
No, you should never use a voltage converter or transformer with this air fryer. It draws a high amount of power, typically 1500 to 1700 watts, and most consumer-grade converters are not rated for such a continuous, high-wattage load. Using one creates a significant fire hazard and will void your product warranty. The Cosori TurboBlaze is designed solely for 120V, 60Hz power.
My Cosori air fryer showed E04, but now it won’t turn on even in a 120V outlet. What’s wrong?
If the unit was briefly plugged into a 240V outlet, it may have survived without damage. However, prolonged exposure to double the voltage can damage internal components like the control board or blow a safety fuse. If it’s completely dead after correcting the outlet, an internal component has likely failed, and you will need to contact Customer Support for repair.
Are E01 and E21 the same error? What about E02 and E22?
Yes, they are the same underlying faults. The different code numbers are typically just different firmware versions or regional model variations reporting the same problem: an open or short circuit in the temperature sensor system. Treat them identically. Cease operation and contact support.
What causes the Cosori temperature sensor to fail (E01/E02 errors)?
These sensors can fail due to a manufacturing defect, a physical shock like dropping the unit, extreme thermal stress from constant high-heat use, or normal wear and tear over time. Moisture or grease ingress into the housing could also cause a short circuit. The reason isn’t as important as the response: the unit has correctly identified a failure and locked out heating for your safety.
I get an error code, but my food seems to be cooking. Should I keep using it?
Absolutely not. If an E01, E02, E21, or E22 code is displayed, the heating element should be deactivated. If you see heat, it means the safety system is malfunctioning, which is even more dangerous. Unplug the air fryer immediately and contact support. For E04, the unit should not heat at all.
My Cosori air fryer isn’t showing an error code, but it won’t heat up. What should I do?
That’s a different problem. First, check our guide for when your Cosori air fryer won’t turn on, which covers basic power checks. If it powers on but doesn’t get hot, the issue could be a different component failure not flagged by the standard error codes. For issues with food not crisping properly, our article on why your Cosori air fryer food isn’t crispy may also help.
Official Documentation
Want the full specifications and manufacturer instructions? Download the official Cosori TurboBlaze Air Fryer 6 Qt, PFAS-Free Ceramic Coating, Dark Gray | 90°–450°F, 5 Level Fan Speeds, 9 in 1 Air Fry, Roast manual (PDF).
