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Generac Generator Error Codes: Complete Alarm Code Reference

Quick Answer

Generac standby generators display numeric alarm codes on the Evolution or Nexus controller. The most common codes are 1505 (low oil pressure), 2800 (overcrank - engine failed to start), 1100 (RPM sense loss), and 1902 (governor actuator fault).

Generac standby generators display numeric alarm codes on the Evolution or Nexus controller. The most common codes are 1505 (low oil pressure), 2800 (overcrank - engine failed to start), 1100 (RPM sense loss), and 1902 (governor actuator fault). The Evolution controller stores the last 10 alarm events with timestamps, accessible by pressing OFF then ENTER twice. Generac Mobile Link remote monitoring sends fault codes to your phone app before the audible alarm sounds on some models. Key distinction: Generac uses two different controller generations - the older Nexus has a simpler 2-line LCD, while the newer Evolution has a full graphic display and more detailed diagnostic information.

GeneracGenerator

About These Generac Generator Error Codes

Generac uses numeric alarm codes on the Evolution or Nexus controller. Access fault history: press OFF, then ENTER twice. Most common: 1505 (low oil), 2800 (overcrank), 1100 (RPM loss).

Most Common Error Codes

Low oil pressure from oil level or sensor40%
Overcrank from fuel delivery issue24%
RPM sensor failure14%
Battery voltage low12%
Governor actuator fault10%

Symptoms You May Notice

  • Alarm code on controller display
  • Red alarm light on controller
  • Generator not starting during outage
  • Generator starts then shuts down
  • Audible alarm beeping

Tools Required for Diagnosis

FlashlightMultimeterOil dipstick

How to Identify Your Error Code

1

Read the alarm code on the controller display

Read the alarm code on the controller display. On Evolution controllers, press OFF then ENTER twice to view the fault log with timestamps. Write down the code number.

2

Press the red ALARM RESET button on the controller to clear the alarm

3

Check the Generac Mobile Link app (if equipped) for remote diagnostics

Frequently Asked Questions

How do I read the fault log on my Generac?
On Evolution controllers: press OFF, then press ENTER twice. The display shows stored fault codes with date and time. Scroll with the arrow buttons. On older Nexus controllers: hold ALARM and ENTER simultaneously for 3 seconds.
Can I reset Generac alarms myself?
Yes. Press the red ALARM RESET button on the controller. Some codes (like 2800 overcrank) clear easily, while others (like 1505 low oil) require fixing the underlying cause first. If an alarm returns repeatedly, call an authorized Generac dealer.
What does the red light on my Generac controller mean?
A solid red light means an active alarm. A blinking red light means the generator has shut down due to a fault. Check the display for the alarm code number. Yellow/amber light means a warning (not critical). Green light means ready/running normally.

Related Generac Generator Error Codes

Code: 2800Generac 2800: OvercrankCode: 1505Generac 1505: Low Oil PressureCode: 1100Generac 1100: RPM Sense LossCode: 1902Generac 1902: Governor Fault

Models Known to Experience HUB Errors

This repair applies to most Generac generators with this error code. Common model numbers include:

Guardian 22kW, Guardian 24kW, Guardian 16kW, EcoGen 15kW, Protector 20kW, CorePower 7kW

Last verified for technical accuracy on March 15, 2026