If you are facing Daikin error code U4-01 and don’t know what it means, don’t worry! You are in the right place. I will help you to resolve the issue with the help of this detailed guide.
Keep reading to learn about 4 possible reasons behind this Daikin Error code and its easy fixes. So, let’s not waste any time and get going!
Daikin AC Error Unit Code U4-01: The 4 Potential Reasons
The Daikin error code U4-01 may appear on the air conditioner’s display panel, alerting the user to a fault that has to be fixed. It’s important to quickly diagnose the error code and fix it accordingly.

In case, you get this malfunctioning error code, it can highly damage the air conditioner’s functionality and efficiency. There are four potential reasons that can lead to the Daikin air conditioner issue. Let’s check them out:
1. Potential Power Supply Issue
The Daikin error code U4 could have a power supply problem as one possible reason. The U4 error code can pop up if the power to the Daikin air conditioner is cut off or if there is an issue with the power cord. It is important to confirm that the power cord is plugged in securely and functioning properly.

2. Indoor and Outdoor Units Compressor Wiring Problem
Another potential cause of the Daikin U4 error is faulty or loose wiring connecting the compressor. To resolve this issue:
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- Thoroughly inspect the compressor wiring for loose or damaged connections.
- If you identify any issues, tighten the power cable securely.
- In case, the damage is extensive, consider replacing the wiring or power cable.
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3. Outdoor Unit Fan Motor Issue
The Daikin error code U4 signals potential problems with the outdoor unit’s fan motor or airflow obstruction. Inspect the outdoor unit, check for debris or damage, and reset the system if necessary. If issues persist, consult your user manual for model-specific guidance.

4. Additional Malfunction Possibilities
There are other issues with the air conditioner that may also cause the Daikin error code U4, such as:
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- Sensor issues;
- Control board problems;
- Flaws in other parts.
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It’s best to call a qualified HVAC specialist in these situations. He will help you find and fix these particular problems.
How to Fix Daikin Error Code U4-01?
This issue can be resolved in two different ways. Let’s talk in depth!
1. Clean the Filter and Drain the Pan
Before diving into the steps, it’s important to understand that resolving this issue typically involves cleaning the filter and addressing any potential blockages in the drain pan. These straightforward maintenance tasks can often restore your Daikin air conditioner to optimal functioning:

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- Start by inspecting the filter and the drain pan to ensure they are free of debris.
- Open the front cover of the AC to check for any debris or blockages.
- Examine the filter’s condition, and if it’s dirty or no longer effective, consider replacing it.
- The condensation drain pan can be cleaned easily using a bucket or tub and a water supply. [/su_list]
[su_note note_color=”#9ee7b3″] Note: To completely avoid the Daikin aircon error code, you can frequently wash these filters. [/su_note]
2. Reset the Power Supply
In order, to resolve the power supply system error code, follow these instructions:
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- Ensure the power cord is securely plugged in.
- Confirm that there are no interruptions in the power supply. [/su_list]
However, for minor fan motor issues, consider a power reset:
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- Turn off all switches connected to the unit for approximately 30 seconds.
- Then, if these components are already clear, switch them back on. [/su_list]
[su_note note_color=”#9ee7b3″] Note: Contact a certified service professional if this does not resolve the issue because there might be an electrical issue that needs to be fixed. [/su_note]
2 Easy Methods to Check Daikin AC Error Codes
Do you have a Daikin air conditioner and don’t know what to do when you see an error code? Don’t worry, it’s not always a big problem. I’ll show you two simple methods to check Daikin error codes and learn what they mean.
Method 1: Using the Daikin AC App
Daikin has now developed an app called Daikin Service that allows you to monitor and control your Daikin heating and cooling systems. Till now, these error codes were displayed through a remote, but now I recommend checking the latest version of their app and user manuals for any updates. Here are general steps for checking error codes through the app:

Step 1: Download and Install the App
First, make sure you have the latest version of the “Daikin Service” app installed on your smartphone. You can usually find this app on the Google Play Store for Android devices or the Apple App Store for iOS devices.
Step 2: Pair the App with Your Daikin Aircon System
Open the app and follow the on-screen instructions to pair it with your Daikin indoor unit PCB. This often involves connecting to your system’s Wi-Fi network or scanning a QR code on the unit or in the user manual.
Step 3: Access and Analyze System Information
Once your app is connected to your Daikin system, you should be able to access various settings and information about your HVAC system.
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- There, look for a section or menu within the app that provides information about the current status of your Daikin aircon system.
- If error code information is available in the app, it may be displayed in a “Diagnostics” or “Troubleshooting” section.
- You might see error codes along with descriptions of what each code means.
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Step 4: Troubleshoot the Error
If you encounter an error code, refer to your Daikin aircon user manual or the app’s built-in help section (if available) to understand the meaning of the error code and possible troubleshooting steps.
[su_note note_color=”#9ee7b3″] Note: Some error codes may be accompanied by suggested actions you can take to resolve the issue. Follow these recommendations if provided. [/su_note]
Method 2: With the Remote Control
In case you have a remote control, you can check out the issue by following the guidelines listed below:

Step 1: Open the Remote Control Cover
Firstly, locate the remote control for your Daikin air conditioning or heating system. Now, find the cover or panel at the front of the remote and remove it by sliding.
Step 2: Press and Hold the SETUP Button
Afterward, identify the “Cancel” button. It may be labeled as such or have a similar name. Now, press and hold the “Cancel” button for approximately 5 seconds. This action will initiate a menu or mode for diagnostic or troubleshooting purposes.
Step 3: Navigate to “Checking Error Code”
Following this, use the remote control’s up or down buttons to navigate through the menu options. There, look for and select the option that says “Checking Error Code.”
Step 4: Display the Error Code
Press the “APPLY” button on your remote control. Make sure you’re pointing the remote toward your indoor unit. The remote control’s display should now show a fault code, and you’ll hear a long beep simultaneously. The fault code is the specific error message that will help diagnose the issue with your Daikin aircon system.
[su_box title=”Quick Tip” style=”default” box_color=”#0CB964″] You have two options to exit the diagnostic mode and return your remote control to normal operation. First, press and hold the “Cancel” button for about 5 seconds once again. Alternatively, simply leave your remote control untouched for approximately 60 seconds, and it should automatically revert to its standard mode of operation. [/su_box]
In case to learn this process more smoothly, you can check out the helpful video to gain better assistance.
Resetting Daikin Error Codes: Quick Guide
Resetting your Daikin air conditioner can be a time and cost-saving solution. Different reset techniques can address specific issues, like malfunctioning green lights, thermostats, or timer issues. However, it’s important to know why a reset is recommended for each situation.
Error Code U4-01 Daikin
When you see the U4-01 error code, it means something is not working right. Usually, it’s because either the indoor coil temperature sensor or the outdoor fan motor is having issues. This problem makes the fans in your air conditioner not work properly.

[su_box title=”How to Fix It?” style=”default” box_color=”#0CB964″] To reset your Daikin AC, simply switch it off for a few minutes, and then turn it back on. If the issue continues, inspect the indoor coil temperature sensor and the outdoor fan motor for any signs of damage or loose connections. If you find any issues, try to repair or replace the faulty components. [/su_box]
Daikin VRV U4 Green Light Error Code
If you see the green light Daikin VRV error code U4, it’s a warning that something’s wrong with the control board of your unit. This code usually shows up when there’s a problem with the wires, like a short circuit, or when the temperature sensor isn’t working right.
[su_box title=”How to Fix It?” style=”default” box_color=”#0CB964″] Check all the wiring connections and sensors on your Daikin VRV unit and then follow the tips listed below:
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- Make sure there are no loose wires or visible damage.
- If you find any issues, fix or replace the affected wires or sensors.
- Reset the unit by turning it off and on to see if the error code U4 clears. [/su_list] [/su_box]
Daikin Error Code U4-00 for Indoor Unit
The Daikin error code U4-00 on your air conditioning unit means that there’s a problem with the fan motor inside the unit. This can happen because of different issues, like damaged wires or worn-out bearings.

[su_box title=”How to Fix It?” style=”default” box_color=”#0CB964″] Inspect the inside fan motor of your air conditioning unit. Look for any damaged wiring or worn-out bearings. If you find any issues, repair or replace the damaged parts. Reset the unit by turning it off and on to check if the error code disappears. [/su_box]
Daikin VRV Error Code U4-01
The Daikin Error Code U4-01 VRV points to a communication problem between different parts of your air conditioning system. This error code happens when there’s damage to the wires or control board, which makes the components not properly connect to or detect each other.
[su_box title=”How to Fix It?” style=”default” box_color=”#0CB964″] Examine the wiring connections of your system to ensure they are properly connected. Look for any visible damage to the wires or control board. If there’s damage, repair or replace the affected components to resolve the error code U4-01. [/su_box]
Daikin Error Code U0
When you see the U0 error code on your Daikin air conditioner, it means there’s a problem with one of the indoor unit parts, like the fan motor or compressor.

[su_box title=”How to Fix It?” style=”default” box_color=”#0CB964″] If you encounter the U0 error code, try resetting your Daikin air conditioner by turning it off and then on again.
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- If the problem continues, examine the indoor unit’s parts, like the fan motor or compressor, for any apparent harm or loose connections.
- Repair or replace any faulty parts you find or call a professional HVAC technician. [/su_list] [/su_box]
What If There Are No Error Codes Shown?
Daikin air conditioners without inverters may not display error codes. If this occurs, there are some tips you can take to address the issue:
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- When no error codes appear, it often indicates compressor overheating, usually resolved with a chemical coil cleaning.
- If problems persist, specific electrical repairs may be needed, best handled by a qualified technician.
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[su_note note_color=”#FFBFBF”] Be cautious: If the compressor keeps running when the interior unit is off, it can lead to indoor freezing and water leakage. Seek professional HVAC technician assistance for unusual behavior. [/su_note]
FAQ
How do you clear a Daikin error code?
How do I diagnose Daikin’s error code?
What is the blinking code for Daikin?
What is the red light on the Daikin error?
Conclusion
The final say is that the Daikin Error Code U4 01 indicates a malfunction within the unit, potentially caused by a faulty electrical connection or component failure. In case, if you suspect an electrical issue, inspect wiring connections for damage.
However, if a component failure is suspected, consider testing or replacing the damaged air conditioner part. If nothing turns out in your favor, it is best to get in touch with an HVAC professional or Daikin Support.
Have you encountered this error code before? If yes, Share your experiences and tested solutions in the comments below.
