F4
UnclassifiedCooling
What This Code Means
Engine shut-down; Coolant temperature fault indicator lights up; Engine shutdown; Engine oil pressure fault indicator lights up; Spare shutdown indicator lights up; Fuse (F4) activates; Alternator charging indicator (L3) does not go out after starting; Failing alternator; AC shutdown indicator (L4) lights up; Overspeed shutdown indicator (L5) lights up; Engine coolant temperature fault indicator (L6) lights up; Engine oil pressure fault indicator (L7) lights up
Possible Causes
- •Engine oil pressure drops to 7.25 psi (0.5 bar)
- •Engine coolant temperature reaches 221 °F (105 °C)
- •High engine coolant temperature
- •Low engine oil pressure
- •Low fuel level
- •Current from the battery to the engine control circuit exceeds its setting
- •Alternator is failing
- •No AC input is present
- •Engine speed has exceeded 115 % of the nominal speed
Related Atlas Copco Fault Codes
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