OS
UnclassifiedCooling
What This Code Means
Common fault/prealarm line 1 activated; Common fault/prealarm line 2 activated; Fault lamp activated (activelow); Common fault/prealarm line activated; Fault lamp activated; Shutdown occurs if the engine coolant temperature exceeds the maximum temperature for more than 5 seconds; Shutdown occurs if a low oil pressure condition exists for more than 5 seconds; Shutdown occurs after 3 unsuccessful starting attempts; No engine rotation is sensed during cranking
Possible Causes
- •AHET (Anticipatory high engine temperature) fault
- •ALOP (Anticipatory low oil pressure) fault
- •AUX (Auxiliary) fault
- •Anticipatory high engine temperature (AHET) fault
- •Anticipatory high engine temperature (AHET) fault (Terminal 40)
- •Anticipatory low oil pressure (ALOP) fault
- •Anticipatory low oil pressure (ALOP) fault (Terminal 41)
- •Auxiliary (AUX) Fault
- •Auxiliary (AUX) fault
- •Auxiliary (AUX) fault (Terminal 26)
- •Batterycharger fault
- •Batterychargerfault
- •Blocked air inlets and exhaust outlets
- •ES (Emergency stop) fault
- •Emergency stop (ES) fault (Terminal 48)
- •Fuel supply issue
- •HET (High engine temperature) fault
- •High Engine Temperature (HET) Fault
- •High engine temperature (HET) fault
- •High engine temperature (HET) fault (Terminal 36)
- •LF (Low fuel) fault
- •LOP (Low oil pressure) fault
- •LWT (Low water temperature) fault
- •Leaks in the lubrication system
- •Low Oil Pressure (LOP) Fault
- •Low Water Temperature (LWT) Fault
- •Low battery volts
- •Low fuel
- •Low fuel (LF) fault
- •Low fuel (LF) fault (Terminal 63)
- •Low oil level
- •Low oil pressure (LOP) fault
- •Low oil pressure (LOP) fault (Terminal 38)
- •Low water temperature (LWT) fault
- •Low water temperature (LWT) fault (Terminal 35)
- •OC (Overcrank) fault
- •OC, AUX, LWT, HET, LOP, OS, AHET, ALOP, and LF faults
- •OS (Overspeed) fault
- •Overcrank (OC) Fault
- •Overcrank (OC) fault
- •Overcrank (OC) fault (Terminal 12)
- •Overspeed (OS) Fault
- •Overspeed (OS) fault
- •Overspeed (OS) fault (Terminal 39)
- •Spark plug issue
Suggested Actions
- 1Activate audiovisual alarm or common fault relay
- 2Check for blocked air inlets and exhaust outlets
- 3Check for leaks in the lubrication system
- 4Check for loose connections
- 5Check the battery
- 6Check the fuel supply
- 7Check the oil level and add oil if the level is low
- 8Check the oil level at the engine
- 9Check the spark plug
- 10Connect A/V Alarm or Common Fault Relay Kit to terminal TB1-32
- 11Connect a remote annunciator and/or audiovisual alarm kit as an indicator with a dry contact kit connected to controller terminal strip TB1.
- 12Connect battery charger alarm contact to TB1-61 to activate fault lamp (activelow) (if used).
- 13Connect battery charger alarm contact to TB1-62
- 14Connect battery charger alarm contact to TB1-62 to activate fault lamp (activelow) (if used).
- 15Connect batterycharger alarm contact to TB1-61
- 16Connect fuel level sensor to TB1-63
- 17Connect fuel level sensor to TB1-63 to activate fault lamp (activelow) (if used).
- 18Contact an authorized distributor/dealer for service if problem continues
- 19Use a remote annunciator and/or A/V alarm kit as an indicator with a dry contact kit connected to controller terminal strip TB1
- 20Use a remote annunciator and/or audiovisual alarm kit as an indicator with a dry contact kit connected to controller terminal strip TB1
Related Rehlko Fault Codes
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