What Causes the UU Code on Kohler Generators

What Causes the UU Code on Kohler Generators?

Ian Mutuli
Updated on
Ian Mutuli

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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UU code is also known as under-voltage shutdown. What Causes the UU Code on Kohler Generators? The code UU indicates that the generator's onboard diagnostic electronics have detected a low AC output. The system will shut down if the voltage falls below 80% of the nominal system voltage for more than 10 seconds to safeguard itself.

Under the low AC output condition, the generator set shuts down automatically, and the control board displays a fault UU code. The controller also displays engine runtime, crank cycle status, high engine temperature, over crank issue, fuel pump relay and low oil pressure. The generating set will not resume until the fault state has been resolved and the ADC controller has been reset.

When a battery voltage issue is resolved, the controller automatically resets. The generator's shutdown remote switch is automatically reset when the problem is fixed. The high engine temperature remote start switch automatically resets when the generator set cools.

The issue, however, does not go away until the controller is rebooted. To resolve this issue, refer to your service manual for safety precautions, reduce the load on the generator and restart it. Contact Kohler engines customer service or an authorized distributor/dealer for assistance if the problem persists.

What is the Procedure for Resetting My Kohler Generator?

  1. Go outside to the generator, open the lid, press the blue OFF button on the generator controller and wait for a few seconds.
  2. Push the blue RUN button next. The generator will either start or attempt to start three times.
  3. Let it run for 5 minutes before pressing the blue OFF button if it starts.
  4. Please wait 30 seconds for it to completely shut down before pressing the blue AUTO button to return it to standby mode.
  5. It will clear the issue and reset the controller.

Frequently Asked Questions(FAQs)

1. What Causes a Kohler Generator to Fail?

Most portable generators fail to produce energy due to the loss of residual magnetism. Generators transfer electrical conductors through a magnetic field. Your generator is devoid of magnets. It can also happen if a generator is run without a load for an extended period.

2. What is the best way to troubleshoot a gas generator?

Before troubleshooting a portable generator, always check the fuel tank to ensure you have enough fuel. There's always the possibility that you're getting a misleading fuel level reading while the tank is genuinely empty. In addition, you may have an oil leak.

Examine the spark plugs. Check to see whether the spark plugs have any evidence of wear and tear. Examine the Air Filter. Examine the battery. Examine the oil level.

3. Does a Generator use more Gas when more Things are Plugged in?

When the wattage of the TV and refrigerator is lower than the AC, the generator uses less gas. It consumes more gas if it is higher. More load equals more power, which equals more fuel. Assuming your generator's capacity isn't exceeded. The fuel intake is controlled by a device known as a governor.

4. How do I test an AVR on My Generator?

You can perform a simple test with the AVR still mounted on the AC generator. Watch what happens to the AC generator output voltage when you adjust the voltage trim pot. A variable output Autotransformer (variac) and a test load that replicates the AC generator field resistance can also be used to bench test any AVR.

5. What Happens if a Generator is Overworked?

An overloaded generator may cause intermittent power to rise, causing damage to any other equipment directly linked to your generator. Consequently, soot begins to form in your generator's exhaust.

6. How Do I Prevent My Generator from becoming Overloaded?

Identify any non-essential circuits for gadgets or equipment you can live without during the power outage and switch them off. Set a timer for when the essential dedicated circuits can be turned on and only run one at a time. It will prevent the generator from becoming overloaded and the voltage from falling.

7. How Can I Tell if My Kohler Generator or Regulator is Malfunctioning?

Suppose your electrical equipment doesn't come on. It could be due to a faulty voltage regulator, which could either be allowing no power through or allowing too much, causing damage to the other components.

Featured Image Credits: couponxoo.com

Ian Mutuli

About the author

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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