Home Error Code Fix Error Code 1505 Generac: How to Fix RPM Sense Loss

Error Code 1505 Generac: How to Fix RPM Sense Loss

by Timothy Ginn

To fix Error Code 1505 on a Generac generator, clear the active fault by pressing the OFF button, then the ON button. This error typically indicates a problem with the fuel pump and may cause the unit to not crank or trigger a shutdown.

It will not self-clear and may be resolved by troubleshooting the fuel pump or contacting a professional for assistance.

Introduction To Error Code 1505 Generac

Explanation of Error Code 1505 Generac

Error Code 1505 Generac, also known as RPM Sense Loss error, is a common issue faced by Generac generator users. This error occurs when there is a problem with the RPM (Rotations Per Minute) sensor, which is responsible for monitoring the engine’s speed. When the RPM sensor detects a loss of RPM signal, it triggers the error code 1505, indicating a potential problem with the generator’s fuel pump.

Common causes of RPM Sense Loss error

There are several factors that can lead to the RPM Sense Loss error in a Generac generator. These include:

  1. A faulty RPM sensor: If the RPM sensor becomes damaged or malfunctions, it may fail to detect the engine’s speed accurately, leading to the RPM Sense Loss error.
  2. Wiring issues: Poorly connected or damaged wiring between the RPM sensor and the generator’s control panel can result in a loss of RPM signal, triggering the error code 1505.
  3. Generator overload: When a Generac generator is overloaded with excessive electrical load, it can put strain on the engine, causing the RPM to drop and resulting in the RPM Sense Loss error.
  4. Fuel pump problems: A malfunctioning fuel pump can lead to insufficient fuel supply to the engine, causing a drop in RPM and triggering the error code 1505.

Importance of fixing RPM Sense Loss error

Fixing the RPM Sense Loss error is crucial for ensuring the optimal performance and longevity of your Generac generator. Ignoring or neglecting this error can have severe consequences, including:

  • Generator shutdown: The RPM Sense Loss error will trigger an automatic shutdown of the generator whenever it occurs. This can leave you without a backup power source, especially during critical times.
  • Potential engine damage: A faulty RPM sensor or problems with the fuel pump can result in the engine running at incorrect speeds or not receiving adequate fuel. This can lead to engine damage if not addressed promptly.
  • Inaccurate monitoring: The RPM sensor plays a vital role in monitoring the engine’s speed and performance. If the sensor is not functioning correctly, it can affect the accuracy of engine diagnostics and prevent timely identification of any underlying issues.
  • Increased repair costs: Ignoring the RPM Sense Loss error can exacerbate any underlying problems, leading to more extensive damage and higher repair costs down the line.

Therefore, it is essential to address the RPM Sense Loss error promptly and seek professional assistance for diagnosis and repairs. By doing so, you can ensure uninterrupted power supply and prolong the lifespan of your Generac generator.

Troubleshooting Steps For Rpm Sense Loss Error Code

If you’re facing the RPM Sense Loss Error Code (1505) on your Generac generator, there are a few troubleshooting steps you can take to resolve the issue. This error code typically indicates a problem with the fuel pump in the generator. Here are the steps you can follow to troubleshoot and fix the RPM Sense Loss Error Code:

Checking the Fuel Pump Connection

One of the first things you should do is check the fuel pump connection in your Generac generator. A loose or faulty connection can cause the RPM Sense Loss Error Code. Ensure that the fuel pump is securely connected and that there are no loose or damaged wires. If you find any issues with the fuel pump connection, fix them accordingly.

Verifying the Fuel Level in the Generator

Another step to troubleshoot the RPM Sense Loss Error Code is to check the fuel level in your Generac generator. Low or empty fuel can also trigger this error. Verify that the generator has an adequate fuel supply and fill it up if necessary. Ensure that the fuel is clean and free from any contaminants that could affect the performance of the generator.

Testing the RPM Sensor

The RPM sensor is responsible for detecting the rotation speed of the generator. A faulty or malfunctioning RPM sensor can cause the RPM Sense Loss Error Code. To test the RPM sensor, you can use a multimeter to measure the voltage across the sensor terminals. Compare the measured voltage with the manufacturer’s specifications to determine if the RPM sensor is functioning correctly. If the sensor is faulty, it may need to be replaced to resolve the error.

Resetting the Error Code

If you have checked the fuel pump connection, verified the fuel level, and tested the RPM sensor, but the error code persists, you can try resetting it. To reset the error code, follow these steps:

  1. Press the OFF button on your Generac generator to turn it off.
  2. Wait for a few seconds and then press the ON button to turn the generator back on.
  3. Monitor the generator’s operation to see if the error code clears.

If the error code persists even after resetting, it’s advisable to contact a professional technician or Generac customer support for further assistance.

By following these troubleshooting steps for the RPM Sense Loss Error Code on your Generac generator, you can identify and resolve the underlying issue. It’s essential to address this error promptly to ensure the proper functioning and reliability of your generator.

Preventive Measures To Avoid Rpm Sense Loss Error

Regular maintenance of the generator

Regular maintenance is essential for keeping your generator in optimal condition and preventing RPM sense loss errors. By following a maintenance schedule, you can identify and address any potential issues before they lead to a complete breakdown. Here are a few key maintenance tasks to consider:

  • Change the oil regularly to ensure proper lubrication of the engine.
  • Replace spark plugs as needed to maintain efficient combustion.
  • Inspect and clean the air filter to prevent clogging and ensure proper airflow.
  • Check and tighten any loose connections, including electrical and fuel lines.

Cleaning and inspecting the fuel pump

The fuel pump plays a crucial role in supplying fuel to the generator’s engine. If the fuel pump becomes dirty or clogged, it can lead to RPM sense loss errors. To prevent this, it’s important to regularly clean and inspect the fuel pump. Here’s how you can do it:

  1. Turn off the generator and disconnect the fuel supply.
  2. Remove the fuel pump cover and carefully clean the pump using a soft brush or cloth.
  3. Inspect the pump for any signs of damage or wear, such as cracks or leaks.
  4. If necessary, replace the fuel pump with a new one to ensure optimal performance.

Monitoring fuel levels and RPM readings

Monitoring the fuel levels and RPM readings of your generator is crucial for avoiding RPM sense loss errors. Here’s what you can do to ensure proper monitoring:

  • Regularly check the fuel level in the generator’s tank and refill as needed.
  • Use a fuel stabilizer to prevent the build-up of contaminants and ensure the fuel remains clean.
  • Monitor the generator’s RPM readings using the control panel or a separate RPM gauge.
  • If you notice any fluctuations or abnormal readings, investigate the issue further to prevent potential RPM sense loss errors.

By following these preventive measures, you can maintain the optimal performance of your generator and minimize the risk of RPM sense loss errors. Remember to conduct regular maintenance, clean and inspect the fuel pump, and monitor fuel levels and RPM readings to ensure the smooth and uninterrupted operation of your generator.

Frequently Asked Questions Of Error Code 1505 Generac

How Do I Fix Generac Error Code 1505?

To fix Generac error code 1505, press the OFF button to clear the active fault. Check for cranking issues and ensure the battery is charged.

What Is Error 1505?

Error 1505 is an RPM loss alarm on a Generac generator, indicating a problem with the fuel pump. It will trigger a shutdown and requires manual intervention to clear the fault.

How Do I Clear My Generac Error Code?

To clear your Generac error code, press the OFF button to clear the active fault.


To resolve the Error Code 1505 Generac, it is crucial to address the underlying issue causing the RPM sense loss. One common cause is a problem with the fuel pump in the Generac generator. This issue triggers an RPM loss alarm and leads to an automatic shutdown that cannot be self-cleared.

Another potential reason for the error code is a low battery, which can result in a cranking issue. It is recommended to check the battery voltage using a voltmeter or charge the battery with a charger. Clearing the active fault by pressing the OFF button is also essential for the unit to crank properly.

By understanding and addressing these potential causes, users can effectively troubleshoot and resolve the Error Code 1505 Generac, ensuring their generator operates smoothly and reliably.

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