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GENERATORCODES

Home / Generac / 1200

Evolution 1.0 / 2.0

1200

Overspeed, prolonged

Engine · Alarm

Alarm 1200 is prolonged overspeed. On a 60 Hz set the table describes frequency over the specified limit (72 Hz) for 3 seconds. On a 50 Hz set the same row uses 60 Hz. The listed cause is the stepper motor or mixer body.

Seen on: Air-cooled home standby generators with an Evolution 1.0 or 2.0 controller.

Likely causes

  • Stepper motor or mixer (throttle) unplugged, jammed, or otherwise holding engine speed up.
  • This is a speed alarm. It is not e-code 1300.

Checks an owner can do

  1. Leave the generator shut down. Do not keep clearing 1200 and letting it restart.
  2. A look for an obvious disconnected stepper plug is reasonable only with the battery disconnected and no attempt to run the set.

When to call a pro

The manual sends this alarm to the stepper-motor and mixer tests. Fuel-mixer work is technician work, and an overspeed can damage the alternator.

Source

Generac Diagnostic Repair Manual 10000041488 (Evolution 1.0/2.0 air-cooled). E-code rows below match that manual's alarm table as published by Home Generators for Sale and the manual text extracted from document 10000041488.

Wording follows that document. Firmware can change a threshold. If this page and the manual shipped with your unit disagree, follow the manual.

What fixed mine

No approved reports for this code yet. Send one. It stays in the review queue until it is approved.

Related Generac codes

https://generatorcodes.com/brand/generac/1200