This guide walks you through how to bypass the humidity sensor on an LG dehumidifier safely and effectively. Whether your unit won’t turn on or keeps shutting off prematurely, this fix can restore continuous operation—without damaging your appliance.
Quick Answers to Common Questions
Can I use a resistor instead of a jumper wire?
Yes! A 47kΩ resistor often works better than a direct wire, as it mimics normal sensor resistance and prevents error codes on some LG models.
Will bypassing the sensor damage my dehumidifier?
No, it won’t damage the unit. But it removes humidity control, so monitor moisture levels to avoid over-drying.
How do I know if the sensor is really faulty?
Use a multimeter to test resistance. If it reads 0 or OL, or doesn’t change with humidity, it’s likely bad.
Can I reverse the bypass later?
Absolutely. Simply remove the jumper wire and reconnect the original sensor (if functional) or install a new one.
Is there a way to clean the sensor instead of bypassing?
Yes—gently clean the sensor with compressed air or a soft brush. Avoid liquids. Sometimes dust buildup causes false readings.
Introduction: Why You Might Need to Bypass the Humidity Sensor
If your LG dehumidifier suddenly stops working—or refuses to turn on even when the room feels damp—it could be due to a faulty humidity sensor. These sensors are designed to measure ambient moisture and signal the compressor to cycle on or off based on your set humidity level. But over time, dust buildup, electrical faults, or calibration drift can cause them to malfunction.
When the sensor fails, your dehumidifier might interpret the air as “dry enough” even when it’s not, shutting off prematurely. Or worse, it might think the air is too humid and refuse to start at all. In these cases, bypassing the sensor can restore functionality—especially if you need continuous dehumidification in basements, crawl spaces, or during flood recovery.
This guide will show you exactly how to bypass the humidity sensor on an LG dehumidifier safely, step by step. We’ll cover tools needed, safety precautions, identification of the sensor, wiring methods, and post-bypass monitoring. While we encourage professional repair when possible, this DIY fix is a proven solution for many common LG dehumidifier issues.
Understanding How the Humidity Sensor Works
Before diving into the bypass, it helps to understand what the humidity sensor does. In LG dehumidifiers, the sensor—often called a capacitive humidity sensor—measures the moisture content in the air passing through the unit. It sends this data to the control board, which then decides whether to run the compressor.
Most LG models use a simple two-wire sensor that varies its resistance based on humidity. At high humidity, resistance drops; at low humidity, it rises. The control board reads this change and activates or deactivates the compressor accordingly.
When the sensor fails, it might send a constant “low humidity” signal (causing the unit to shut off) or a “high humidity” signal (preventing startup). Bypassing it tricks the control board into thinking the air is always humid enough to run—effectively putting the dehumidifier into continuous operation.
Note: This bypass does not damage the unit, but it removes automatic humidity control. You’ll need to monitor moisture levels manually to avoid over-drying, which can cause discomfort or damage to wood and furniture.
Tools and Materials You’ll Need
Gather these items before starting:
- Phillips and flathead screwdrivers
- Needle-nose pliers
- Wire strippers
- Electrical tape or heat shrink tubing
- Small piece of insulated wire (18–22 gauge, ~6 inches long)
- Multimeter (optional but recommended)
- Safety gloves and goggles
- Work light or flashlight
Optional: Soldering iron and solder (for a more permanent connection), but not required.
Safety Precautions Before You Begin
Working inside an appliance carries risks. Follow these safety steps:
Unplug the Unit
Always disconnect the dehumidifier from the power outlet. Do not rely on the power switch—unplug it completely.
Visual guide about How to Bypass the Humidity Sensor on a Lg Dehumidifier
Image source: m.media-amazon.com
Discharge Capacitors
Dehumidifiers store electrical energy in capacitors, even when unplugged. To discharge them, wait 10–15 minutes after unplugging, then briefly touch the capacitor terminals with an insulated screwdriver (with the unit unplugged). This prevents accidental shocks.
Work in a Dry, Well-Lit Area
Moisture increases shock risk. Choose a dry workspace with good lighting to see small components clearly.
Wear Protective Gear
Safety gloves protect against sharp edges; goggles prevent dust or debris from entering your eyes.
Avoid Static Electricity
Touch a grounded metal object before handling circuit boards to discharge static, which can damage sensitive electronics.
Step 1: Access the Internal Components
Every LG dehumidifier model varies slightly, but the general disassembly process is similar.
Remove the Front Panel or Cover
Most LG dehumidifiers have a front grille or panel held by screws or clips. Use a Phillips screwdriver to remove screws along the top, sides, or bottom. Gently pry off clips with a flathead screwdriver if needed.
Locate the Control Panel
Once the front is off, you’ll see the control board—usually mounted near the top. It’s a small circuit board with wires connected to buttons, displays, and sensors.
Find the Humidity Sensor
The humidity sensor is typically a small, round or rectangular component with two wires attached. It’s often mounted near the air intake, behind a mesh screen, or clipped to the evaporator coil housing. Look for a white or beige plastic housing with two thin wires (usually red and white or blue and white).
Tip: Consult your user manual or search online for your specific model (e.g., “LG LD501ELF humidity sensor location”) if you’re unsure.
Step 2: Identify the Sensor Wires
Once you’ve located the sensor, trace the two wires back to the control board. They usually connect via a small plug or are soldered directly.
Label the Wires (Optional but Helpful)
Use a piece of tape to mark each wire (e.g., “Sensor Wire A” and “Sensor Wire B”) so you don’t mix them up during reconnection.
Test the Sensor (Recommended)
Use a multimeter to check the sensor’s resistance. Set the meter to ohms (Ω). Disconnect the sensor wires from the board, then touch the probes to the sensor terminals.
- At room temperature and normal humidity (50–60%), resistance should be between 10kΩ and 100kΩ.
- If the reading is 0Ω (short) or OL (open circuit), the sensor is likely faulty.
- If resistance doesn’t change when you breathe on the sensor (increasing humidity), it’s not responding properly.
If the sensor tests fine, the issue may be elsewhere—check the control board or wiring.
Step 3: Bypass the Sensor with a Jumper Wire
Now for the core step: creating a bypass.
Disconnect the Sensor Wires
Carefully unplug or desolder the two wires from the control board. If they’re plugged in, gently pull the connector. If soldered, use a soldering iron to melt the joint and remove the wire.
Prepare the Jumper Wire
Cut a 6-inch piece of insulated wire. Strip about 1/4 inch of insulation from both ends using wire strippers.
Connect the Jumper
Twist one end of the jumper wire to one sensor terminal on the control board, and the other end to the second terminal. Secure with electrical tape or, better yet, solder for a permanent connection.
What this does: The jumper wire creates a fixed resistance path, simulating a constant “high humidity” signal. The control board thinks the air is always damp, so it keeps the compressor running.
Tip: For a cleaner look, you can solder the jumper directly to the sensor’s original connection points on the board.
Step 4: Reassemble the Dehumidifier
Once the bypass is in place, carefully put everything back together.
Secure All Components
Make sure no wires are pinched or loose. Tuck the jumper wire neatly away from moving parts like fans or coils.
Reattach the Front Panel
Align the panel and reinsert screws or clips. Don’t overtighten—snug is enough.
Double-Check Connections
Before plugging in, visually inspect all connections. Ensure the jumper is secure and no tools or debris are left inside.
Step 5: Test the Dehumidifier
Now it’s time to see if the bypass worked.
Plug In and Power On
Reconnect the dehumidifier to power. Turn it on using the control panel.
Listen for the Compressor
Within 30–60 seconds, you should hear the compressor start and the fan begin spinning. If it runs continuously (without cycling off), the bypass is successful.
Check for Error Codes
Some LG models display error codes (e.g., “CH” for sensor issues). If an error appears, double-check your wiring or try a different jumper resistance (see troubleshooting below).
Troubleshooting Common Issues
Even with a proper bypass, problems can arise. Here’s how to fix them.
Unit Still Won’t Turn On
If the dehumidifier doesn’t start at all, the issue may not be the humidity sensor. Check the power cord, fuse, or control board. Use a multimeter to test for continuity in the power switch and thermal overload protector.
Compressor Cycles On and Off Rapidly
This could mean the jumper resistance is too low. Try adding a small resistor (e.g., 10kΩ) in series with the jumper to simulate a more realistic humidity level.
Error Code Persists
Some LG models require a specific resistance range. If you see “CH” or “E1,” try a 47kΩ resistor instead of a direct wire. Solder it between the two sensor terminals.
Overheating or Strange Noises
Stop use immediately. This could indicate a blocked airflow, faulty fan, or electrical issue unrelated to the sensor.
Water Leakage
If the unit leaks after reassembly, check that the drain hose or bucket is properly seated. Also, ensure the evaporator coil isn’t obstructed.
Alternative: Use Continuous Mode (If Available)
Before bypassing, check if your LG dehumidifier has a built-in continuous mode. Many models (like the LD501ELF or LD701ELF) include a “Continuous” or “Turbo” setting that runs the compressor nonstop, ignoring the humidity sensor.
To activate:
- Press the “Mode” or “Function” button until “Continuous” appears on the display.
- Set the fan speed to high for maximum airflow.
This is the safest and easiest solution—no disassembly required. Only bypass the sensor if continuous mode isn’t available or doesn’t work.
Post-Bypass Monitoring and Maintenance
Once bypassed, your dehumidifier will run continuously. This is effective but requires attention.
Use a Standalone Hygrometer
Place a digital hygrometer in the room to monitor humidity levels. Ideal indoor humidity is 30–50%. If it drops below 30%, turn off the dehumidifier to prevent over-drying.
Empty the Water Tank Regularly
Continuous operation fills the tank faster. Check it every few hours during heavy use.
Clean the Air Filter Monthly
A dirty filter reduces efficiency. Remove and wash the filter with mild soap and water, then dry completely before reinstalling.
Inspect for Frost Buildup
In cold environments, the evaporator coil may frost over. If you see ice, turn off the unit and let it defrost. Consider using the dehumidifier only in temperatures above 65°F (18°C).
When to Avoid Bypassing the Sensor
While bypassing is effective, it’s not always the best solution.
Under Warranty
If your LG dehumidifier is still under warranty, bypassing may void it. Contact LG support or an authorized repair center first.
Suspected Control Board Failure
If the sensor tests fine but the unit still won’t work, the control board may be faulty. Bypassing won’t help—and could cause further damage.
High Energy Costs
Continuous operation increases electricity use. Only use bypass mode when necessary, such as during water damage restoration.
Unstable Power Supply
In areas with frequent power surges, running the compressor nonstop increases wear. Use a surge protector if possible.
Conclusion: A Practical Fix for a Common Problem
Bypassing the humidity sensor on an LG dehumidifier is a straightforward, effective solution when the sensor fails. By following this guide, you can restore continuous operation without replacing expensive parts or calling a technician.
Remember: Safety comes first. Always unplug the unit, discharge capacitors, and work carefully. Use a multimeter to confirm sensor failure, and consider using a resistor instead of a direct wire for better compatibility.
While bypassing removes automatic humidity control, it’s a reliable workaround for basements, garages, or emergency drying. Just monitor moisture levels with a hygrometer and maintain the unit regularly.
If your dehumidifier is under warranty or you’re uncomfortable with electronics, seek professional help. But for most users, this DIY fix saves time, money, and frustration.
With the right tools and precautions, you can keep your LG dehumidifier running smoothly—even when the sensor says otherwise.