Rehlko

FS (1A-T)

UnclassifiedElectrical

What This Code Means

Abnormal low voltage, charger is operating; Battery is discharged, but the charger has power and is operating; Charger not operating; Red LED stays on for more than 24 hours; Red and green LEDs stay on for more than 24 hours; Green LED stays on when the battery is known to be below (normal charge level); Neither of the LEDs turn on when the AC power is applied; Green LED is off and there is no output voltage

Possible Causes

  • •Battery completely discharged
  • •Charger operating at current limit
  • •Blown fuse
  • •No power to the charger
  • •One or more inoperative or damaged cells
  • •Battery charger has reduced its output voltage below the normal level due to a DC overload or a DC short
  • •Onboard DC systems are drawing more current than the battery charger can replace
  • •Onboard DC systems are drawing between 1.5 and 5 amps
  • •Extremely low AC voltage at the battery charger
  • •Open DC output fuse (AGS-10)
  • •Faulty or contaminated terminal connections
  • •No AC power available at the battery charger
  • •Component failure
  • •No power to the battery charger
  • •Check the upstream circuit breakers and fuses
  • •Check fuse FS (1A-T) inside the battery charger

Suggested Actions

  1. 1Disconnect the battery and verify that the charger output is 13.2 VDC
  2. 2Reconnect the charger and allow time for the battery to recharge
  3. 3Battery voltage should rise gradually
  4. 4Test the battery
  5. 5Check the 5-amp fuse F2 (5A-T) inside the battery charger and replace if necessary
  6. 6Check inline fuse F4 and replace if necessary
  7. 7Check the power supply to the charger
  8. 8Check the upstream circuit breakers and fuses
  9. 9Check fuse FS (1A-T) inside the battery charger
  10. 10Load test the battery and replace, if necessary
  11. 11Remove the source of the overload or short. Disconnect the battery charger’s black (NEGATIVE) ring terminal from the battery. Reapply AC power and the green LED only should now light.
  12. 12Turn off all DC equipment while charging.
  13. 13Load test the battery and replace, if necessary.
  14. 14Apply a higher AC voltage source or reduce the length of the extension cord.
  15. 15Replace AGS-10 fuse.
  16. 16Clean and tighten or repair all terminal connections.
  17. 17Connect AC power or reset the AC breaker on the main panel.
  18. 18Replace battery charger.
  19. 19Check the power supply to the charger.
  20. 20Check the upstream circuit breakers and fuses.

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