2099
What This Code Means
Generator running underspeed for > 30 seconds when undervoltage alarm set; Single Zero Cross missing; Undervoltage due to faulty excitation winding, or zero cross circuit, or circuit in general; One zero cross missing for greater than 1.5 seconds; Field Current measured value is above threshold; The controller fuse is missing or damaged in such a way that it does not work; Fuse problem must be detected for 1.5 seconds; Command and position feedback not matching or taking too much time to achieve; Governor in open position for greater than one second; Governor in closed position (commanded otherwise) for greater than one second; Prolonged Undervoltage; Generator voltage below 80% of nominal for 10+ seconds.; Both Zero Crosses missing Undervoltage; Controller measuring no voltage resulting in undervoltage; Generator voltage less than 120V when undervoltage set; No field current during undervoltage alarm; Generator running underspeed for > 30 seconds when under - voltage alarm set; Single
Possible Causes
- •Broken wire
- •Brushed Alternator Problem 1 – Generator Shuts Down for Under Voltage page 53
- •Brushless Alternator Problem 5 – Generator Shuts Down for Under Voltage page 57
- •Circuit in general failure
- •Customer connection low voltage and high voltage wires are crossed
- •Faulty excitation winding
- •Field boost hardware failure
- •Firmware older than V1.30
- •Loose connections
- •Loose wiring
- •Missing / Damaged Fuse
- •Zero cross circuit failure
- •circuit in general
- •engine intake exhaust or mechanical issues
- •faulty excitation winding
- •field boost hardware failure
- •fuel supply/control system
- •governor module
- •governor wire loose
- •overload
- •zero cross circuit
Suggested Actions
- 1Check customer connection in generator
- 2Contact Technical Support.
- 3Procedure for Alarm E-Code 1905
- 4Procedure for Alarm E-Code 1916
- 5Procedure for Alarm E-Code 2101
- 6Procedure for Alarm E-Code 2400
- 7Procedure for Alarm E-Code 2500
- 8Procedure for Alarm E-Code 2501
- 9Procedure for Alarm E-Code 2502
- 10Remove Load
- 11Test 101 – Check for Short Circuits page 172
- 12Test 28 – Test for an Overload Condition page 75
- 13Test 68
- 14Verify VCC settings.
- 15Verify customer connection wiring.
- 16Verify wiring on Wire 194 and Wire 23.
ASK RUDY ABOUT THIS FAULT
Get a diagnosis walkthrough for 2099 on your specific Generac unit — cited to the OEM manual, not a forum guess.
Free account required — we'll bring your question with you.