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No ac output from generator

Why generators show "no ac output from generator": 23 documented causes and brand-specific fixes, compiled across 7 manufacturers.

Generator internal failure

3 brands
  • Carrier: 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. Contact a dealer facility.
  • Generac: 1. Reset circuit breaker to ON (or CLOSED). 2. *; 1. Reset generator disconnect to ON (CLOSED). 2. * 3. Check the controller screen to verify status.
  • Nexus: 1. Reset to ON/CLOSED. 2. * 3. Auto-reset - Wait 5 min. and attempt restart. *Contact the nearest Dealer for assistance.

Check main line circuit breaker; Check circuit breaker & fuses; Transfer switch set to NORMAL position; Generator internal failure; Thermal circuit breaker open

3 brands
  • Ford: 1. Reset to ON or CLOSED; 2. Reset and replace, if necessary; 3. Set to GENERATOR position; 4. *; 5. Auto-reset - Wait 5 min. and attempt restart
  • GenSpec065: 1. Reset to ON or CLOSED; 2. Reset and replace, if necessary; 3. Set to GENERATOR position; 4. *; 5. Auto-reset - Wait 5 min. and attempt restart
  • Olympian: 1. Reset to ON or CLOSED; 2. Reset and replace, if necessary; 3. Set to GENERATOR position; 4. *Contact the nearest Authorized Dealer for assistance; 5. Auto-reset - Wait 5 min. and attempt restart

Check main line circuit breaker

2 brands
  • Carrier: 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. Contact a dealer facility.
  • Generac: 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. * 5. Auto-reset - Wait 5 min. and attempt restart.; 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. *Contact the nearest Dealer for assistance. 5. Auto-reset - Wait 5 min. and attempt restart.

Check circuit breaker & fuses

2 brands
  • Carrier: 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. Contact a dealer facility.
  • Generac: 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. * 5. Auto-reset - Wait 5 min. and attempt restart.; 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. *Contact the nearest Dealer for assistance. 5. Auto-reset - Wait 5 min. and attempt restart.

Transfer switch set to NORMAL position

2 brands
  • Carrier: 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. Contact a dealer facility.
  • Generac: 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. * 5. Auto-reset - Wait 5 min. and attempt restart.; 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. *Contact the nearest Dealer for assistance. 5. Auto-reset - Wait 5 min. and attempt restart.

Thermal circuit breaker open

2 brands
  • Generac: 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. * 5. Auto-reset - Wait 5 min. and attempt restart.; 1. Reset to ON or CLOSED. 2. Reset and replace, if necessary. 3. Set to GENERATOR position. 4. *Contact the nearest Dealer for assistance. 5. Auto-reset - Wait 5 min. and attempt restart.
  • Nexus: 1. Reset to ON/CLOSED. 2. * 3. Auto-reset - Wait 5 min. and attempt restart. *Contact the nearest Dealer for assistance.

Main line circuit breaker is tripped/open

2 brands
  • Generac: 1. Reset to ON/CLOSED. 2. * 3. Auto-reset - Wait 5 min. and attempt restart. *Contact the nearest Dealer for assistance.; 1. Reset to ON/CLOSED. 2. * 3. Auto-reset - Wait 5 min. and attempt restart.*Contact the nearest Dealer for assistance.
  • Nexus: 1. Reset to ON/CLOSED. 2. * 3. Auto-reset - Wait 5 min. and attempt restart. *Contact the nearest Dealer for assistance.

1. Check main line circuit breaker.

1 brand
  • Generac: Reset to ON or CLOSED.

Check circuit breaker

1 brand
  • Generac: 1. Reset to ON or CLOSED. 2. Reset and replace if necessary. 3. Set to GENERATOR position. 4. Take generator to an Authorized Generac facility.; 1. Reset to ON or CLOSED. 2. Reset and replace if necessary. 3. Take generator to an Authorized Generac facility.

Check vehicle circuit breaker & fuses

1 brand
  • Generac: 1. Reset to ON or CLOSED. 2. Reset and replace if necessary. 3. Set to GENERATOR position. 4. Take generator to an Authorized Generac facility.; 1. Reset to ON or CLOSED. 2. Reset and replace if necessary. 3. Take generator to an Authorized Generac facility.

Transfer sw. set to NORMAL position

1 brand
  • Generac: 1. Reset to ON or CLOSED. 2. Reset and replace if necessary. 3. Set to GENERATOR position. 4. Take generator to an Authorized Generac facility.

1. Check circuit breaker.

1 brand
  • Generac: 1. Reset to ON or CLOSED.

Defective Control Module circuit board

1 brand
  • Generac: *Contact the nearest Authorized Dealer for assistance.; Replace board.*

Defective AUTO/OFF/MANUAL switch Open/disconnected wire #15A between AUTO/OFF/MANUAL switch and Control Module circuit board.

1 brand
  • Generac: 1. Replace switch.* 2. Reconnect/close wire.

Defective AUTO/OFF/MANUAL switch

1 brand
  • Generac: Replace switch.*

Common questions

What causes no ac output from generator?

Common causes, most-reported first: Generator internal failure; Check main line circuit breaker; Check circuit breaker & fuses; Transfer switch set to NORMAL position; Generator internal failure; Thermal circuit breaker open; Check main line circuit breaker; Check circuit breaker & fuses; Transfer switch set to NORMAL position; Thermal circuit breaker open.