How do I test my generator in Manual mode after clearing an error?

Some errors can occur intermittently due to conditions at the time of the event (for example, temporary fuel supply/pressure issues, brief load/voltage changes, or a transient sensor/connection condition). This procedure walks you through clearing an error and performing a short no-load test in Manual mode to see if the condition returns.

If the same error returns, the underlying condition is still present and will need further troubleshooting or service. See here for a list of error codes that require dealer service.

Environment

This article applies to Generac air-cooled home standby generators with the following control panels:

• Power Zone 200
• Evolution 1 / Evolution 2 (Evo 1 / Evo 2)
• Sync 2.0 / Sync 3.0
• Nexus

Before you begin

• Never start or stop the generator while it is under load. To avoid equipment damage, carefully follow these steps in order during utility outages. Immediate shutdown while a generator is running under load can cause damage to engine components: How do I shut down my generator when it’s powering my house (during an outage)?
• Keep people, pets, and combustibles away from the generator while running.
• If you smell gas or see damaged wiring, stop and contact a dealer using the dealer locator.
• Need your owner’s manual for controller button locations? Find it on the product lookup page.

Procedure

IMPORTANT: Do not attempt to run the generator if the error is related to oil pressure, oil temperature, or engine coolant. Doing so may cause engine damage. Contact an Independent Authorized Service Dealer.

Initial troubleshooting steps

• Identify the alarm code: Alarm codes can be identified by checking Mobile Link or the generator’s control panel.
• Consult the owner’s manual: Confirm the meaning of the message/code and review recommended troubleshooting steps for the specific alarm code. Find your manual on the product lookup page.
• Clear alarm: Attempt to clear the alarm and manually restart the unit using the steps below.

1. Clear the error on the control panel

Use the controller-specific method below to clear the error, then return the unit to AUTO unless directed otherwise. For more detailed instructions, see How do I clear an error or alarm code on my home standby generator?

• Next Generation series (Power Zone 200): Press and hold OFF for 3 seconds to clear the error, then press AUTO.
• Evolution 1 / Evolution 2 (Evo 1 / Evo 2): Press OFF, press ENTER twice, then press AUTO.
• Nexus: Move the rocker switch to OFF, press ENTER twice, then move back to AUTO. (For Nexus panels without a rocker, press OFF, then press ENTER twice.)
• Sync 2.0 / Sync 3.0: Press OFF, press ENTER twice, then press AUTO.

2. Prepare for a no-load test in Manual mode

1. Make sure utility power is present. If you are in an outage, confirm the generator is not carrying load before proceeding (set the generator MLCB to OFF).
2. Set the generator’s main line circuit breaker (MLCB) to OFF to ensure a no-load start. For more detail, see What is the generator main line circuit breaker? (MLCB)

3. Start the generator in Manual mode

IMPORTANT: Do not attempt to run the generator if the error is related to oil pressure, oil temperature, or engine coolant. Doing so may cause engine damage. Contact an Independent Authorized Service Dealer.

With the MLCB set to OFF, start the unit using the controller-specific methods below:

• Evolution 1 / Evolution 2 (Evo 1 / Evo 2): Press MANUAL.
• Next Generation series (Power Zone 200): Press MANUAL on the controller.
• Nexus: Move the rocker switch to MANUAL.
• Sync 2.0 / Sync 3.0: Press MANUAL

4. Observe for 3–5 minutes

• Watch Mobile Link or the generator’s control panel for errors and watch the status lights. Listen for smooth running and check for new errors.
• If the same error returns during or shortly after the test, see What to do if the error returns.
• If no error returns, the event may have been caused by temporary circumstances. Proceed to Step 5 to return to service and continue monitoring.

5. Return the generator to service

1. Press OFF to stop the unit (if still running in Manual mode).
2. Set the generator MLCB to ON to restore the path to the home’s electrical system.
3. Press AUTO. The unit is ready to run on utility loss.

What to do if the error returns

Search on this help center for the error-specific article. Examples:

• Overcrank, code 1100
• RPM sense loss, codes 1501/1505/1511/1515
• Undervoltage, codes 1900–1916
• Overload / remove load, codes 2100–2103

IMPORTANT: Do not attempt to run the generator if the error is related to oil pressure, oil temperature, or engine coolant. Doing so may cause engine damage. Contact an Independent Authorized Service Dealer.

Intermittent or difficult-to-replicate error?

If the error is intermittent or difficult to reproduce, see Troubleshooting intermittent or difficult-to-replicate alarms, faults, and error codes.

What to note for intermittent errors

• The exact message/code shown on the control panel and/or in Mobile Link.
• Whether utility power was present and whether the generator was carrying load.
• Fuel type and any known supply/pressure issues in your area.
• Weather conditions and any recent maintenance or wiring work.

Note: During widespread natural gas outages or low fuel pressure events, contact your gas utility. Supply issues can trigger false or transient alarms.

Still seeing the error?

Contact an Independent Authorized Service Dealer via the dealer locator.

See also

• What is the generator main line circuit breaker? (MLCB)
• How do I clear an error or alarm code on my home standby generator?
• How do I run my generator in Manual mode?
• How do I shut down my generator when it’s powering my house (during an outage)?
• Troubleshooting intermittent or difficult-to-replicate alarms, faults, and error codes
• How do I perform a hard reset on a home standby system?
• Where can I find a list of error codes for my generator?
• What error codes do I need to call a dealer for?
• What is the difference between maintenance reminders, warnings, and alarms?
• My generator shows switched to OFF, how do I put it back into AUTO?