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When many people face trouble with their LG dishwashers, their first instinct is to call a qualified technician to troubleshoot and fix the problem. However, that doesn’t have to be the first step you take. Instead, you can use the machine’s diagnostic mode to narrow the problem to its root cause.
You can enter the diagnostic mode (or ‘test’ mode) on an LG dishwasher by pressing the Power and Start buttons simultaneously. There are 7 tests in total, and you can cycle through them manually by pushing the Start button when you’re ready to move to the next stage.
So, before you spend money calling a technician, use the test mode to troubleshoot the problem yourself. This guide will show you how to do that and also explain what each of the 7 tests does.
How Do You Enter Diagnostic Mode On An LG Dishwasher?
Here are the 5 steps you’ll want to follow to enter diagnostic mode on your LG dishwasher and cycle through its many tests:
Step 1: Enter Test Mode
The diagnostic mode on LG dishwashers is commonly called ‘test mode’. So, don’t be confused if you see that term used in the user manual and other technical materials.
Entering the test mode is incredibly straightforward. You only have to press the Power and Start buttons simultaneously.
There are 7 tests will be explained to you in the second half of this guide.
Read: 5 LG Dishwasher Problems You Need To Know
Step 2: Close Dispenser Door And Machine Door
When entering the test mode, close the detergent dispenser door and then close the dishwasher door.
All the lights on the display will turn on while you’re in test mode. You’ll also see the display flashing with numbers or alphabets related to the current test being run.
Step 3: Begin First Test
Next, press Start again to begin the first test. For LG dishwashers, that first one will test your detergent dispenser to ensure it’s working.
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Again, you’ll learn about each of the 7 tests in the next section.
Step 4: Cycle Through Tests
Each of the 7 tests in your LG dishwasher’s diagnostic mode will run continuously until you cycle through to the next one.
You can cycle to the next test by pressing the Start button again.
By having to do that manually, you can control how long each test runs. It also allows you to skip to the specific test you want to perform instead of waiting.
Read: How To Fix LG Dishwasher Which Has No Power?
Step 5: Finish Diagnostic Tests
Finally, you can end and exit the diagnostic mode by pressing the Start button again while the seventh and final test is running.
What Are The Different Diagnostic Tests On An LG Dishwasher?
Earlier, you saw the 5 steps to enter diagnostic mode and cycle through the different tests.
Here is what you need to know about each of those 7 tests:
Test #1: Detergent Dispenser
About this part: The detergent dispenser is responsible for distributing dishwasher detergent during a wash cycle.
This first test ensures that the solenoid can correctly open and close that dispenser door.
What appears on the display: While running the first test, the display will show the sump temperature in Celsius.
Read: How To Fix LE Error Code On LG Dishwasher?
Test #2: Door Vent Blower Motor
About this part: Your LG dishwasher relies on a blower motor to drive air through the door vent. Doing so helps remove excess moisture, speeding up the drying process for your dishes inside.
The second test ensures that the blower motor is working as it should.
What appears on the display: The display will only show that you’re in the second test in the dishwasher’s test mode. It won’t display any other diagnostic information at this time.
Test #3: Soil Sensor
About this part: LG dishwashers also have a soil sensor that measures how dirty the items inside still are. With that information, the dishwasher can lengthen or shorten the cleaning cycle time as needed.
What appears on the display: During this test, the dishwasher will show the current soil level inside the machine.
Test #4: Drain Motor
About this part: Gravity helps to remove used water from the dishwasher. However, there’s also a drain motor that helps to drive water out more efficiently.
The fourth test ensures the drain motor is functioning without clogs, jams, or other problems.
What appears on the display: While the fourth test is running, the display will show the drain motor’s turning speed, measured in revolutions per minute or RPMs.
Test #5: Water Inlet Valve
About this part: The water inlet valve controls water inflow into the dishwasher. The test will ensure that the valve can open, let clean water in, and also shut to prevent overflow.
What appears on the display: The display will show a measurement of how much water is flowing into the dishwasher. Not only must there be an inflow of water, but it should also be at the correct volumes.
Read: How To Reset CL Error Code On LG Dishwasher?
Test #6: Washing Motor
About this part: The washing motor ensures the spray arms are spinning fast enough to wash all your dishes efficiently.
What appears on the display: This test will display data about the washing motor’s turning speed, measured in revolutions per minute or RPMs.
Test #7: Washing Heater Vario Valve
About this part: The final test is responsible for testing the washing heater vario valve. This valve directs water between the upper and lower wash or spray arms inside the dishwasher.
What appears on the display: Some several different numbers and alphabets will appear on the display during this test. Here is what they are and what they mean:
- 1Un: The test is diverting water to the upper wash arm only.
- 1Lo: The test is diverting water to the lower wash arm only.
- 0LO: The test is allowing water to flow to both wash arms simultaneously.
- NE: The test senses that the valve is not working at all.
Read: What Means NE Error Code On LG Dishwasher?
Frequently Asked Questions (FAQs)
Here are a few more questions and answers to help you as you run diagnostics on your LG dishwasher:
How Do I Reset My LG Dishwasher?
If you find that a reset is necessary, you can do so by shutting off the power to the dishwasher. Turning it off is not enough, so you’ll have to pull the plug from the wall socket or shut off the circuit breaker. After a minute passes, you can turn the dishwasher back on, and the reset will be complete.
How Do You Clean The Spray Arm On An LG Dishwasher?
Firstly, take the removable spray arms out of your LG dishwasher. Then, wash the spray arms to remove any buildup of grease or other food stains. Next, grab a toothpick to clean any clogged water jets on those arms.
Can You Use Pods In LG Dishwashers?
Yes, you can use pods in an LG dishwasher. But make sure that those pods only have dishwasher detergent, as any other kind of pods will cause problems for the appliance.
Do LG Dishwashers Recycle Water?
Yes, to increase water efficiency, LG dishwashers recycle some of the water it uses during a wash cycle. That water is filtered to remove any food bits and other impurities before it’s recirculated.
What Does A Vario Valve Do In An LG Dishwasher?
The vario valve in an LG dishwasher controls how water is diverted between the upper and lower wash arms.
