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ErrBase

Generac Generator Error Codes

All Generac generator error codes with step-by-step troubleshooting, multimeter specs, and OEM part numbers.

15 error codes

CodeMeaning
0Code 0 indicates the controller lost communication with one or more sensors or modules. This is a general communication fault similar in concept to a watchdog timeout.
mediumintermediate
1100Code 1100 means the controller lost the RPM signal from the engine speed sensor while the engine was running. Without RPM feedback, the controller cannot regulate engine speed and shuts down as a safety measure.
highintermediate
1300Code 1300 means the generator detected an electrical overload exceeding its rated capacity. The controller shuts down to prevent damage to the alternator and wiring.
highintermediate
1501Code 1501 specifically indicates the oil pressure sensor circuit has a fault - either open circuit, short circuit, or reading out of expected range. Unlike 1505 which indicates actual low oil pressure, 1501 is a sensor circuit problem.
mediumintermediate
1505Code 1505 indicates the engine oil pressure dropped below the safe operating threshold while the engine was running. Generac's controller immediately shuts down the engine to prevent catastrophic bearing damage. This is a critical safety shutdown.
criticalintermediate
1600Code 1600 means engine speed deviated significantly from the target 3600 RPM. The governor system could not maintain proper speed under the current load conditions.
highintermediate
1603Code 1603 indicates the controller detected excessive current draw from the governor stepper motor (iSMA). The motor is either shorted or mechanically jammed.
highintermediate
1900Code 1900 indicates the controller lost the governor position feedback signal. The controller cannot confirm the throttle position.
highintermediate
1902Code 1902 indicates the electronic governor actuator (also called the stepper motor or iSMA - intelligent Speed Management Actuator) has failed to respond to the controller's speed commands. The governor controls engine speed by adjusting the throttle.
highintermediate
2099Code 2099 means engine speed exceeded safe limits. The governor lost control and engine RPM rose above the maximum threshold, triggering immediate shutdown.
criticaladvanced
2100Code 2100 means engine speed dropped below acceptable threshold while running. The engine is bogging down under load.
highintermediate
2400Code 2400 indicates the 12V starting battery voltage has dropped below the minimum threshold. Without adequate battery voltage, the generator cannot crank the engine.
mediumbeginner
2780Code 2780 indicates the ignition system is not producing adequate spark. The controller detected cranking without successful ignition events.
highintermediate
2800Code 2800 on a Generac generator means the engine cranked for the maximum allowed time (typically 10-12 seconds per attempt, 6 attempts) without achieving a stable running speed. The controller detected cranking RPM but never saw running RPM, indicating a fuel delivery or ignition problem.
highintermediate
HUBComplete reference for all Generac standby generator alarm and fault codes. Generac uses numeric error codes displayed on the Evolution or Nexus controller panel, with codes ranging from 0 to 2800+.
mediumbeginner