FAULT CODE 1
UnclassifiedCooling
What This Code Means
Excess White Smoke at Start-Up (Warm); Excess White Smoke at Start-Up (Cold); High Engine Temperature; Low Oil Pressure; Engine oil leak; High engine temperature; Low oil pressure; Overcrank
Possible Causes
- •Engine compression issues
- •Choke operation issues
- •Coolant level issues
- •Grounded or shorted sender lead
- •Temperature sender resistance issues
- •Coolant temperature issues
- •Raw water flow issues
- •Raw water impeller issues
- •Heat exchange blockage
- •Pressure cap issues
- •Oil level issues
- •Broken or loose sender lead
- •Pressure sender open
- •Grounded or shorted gauge lead
- •Sender to control fault
- •Restricted raw water flow
- •Damaged raw water impeller
- •Heat exchanger blockage
- •Faulty pressure cap
- •Low oil level
Suggested Actions
- 1Check engine compression
- 2Check choke operation
- 3Check coolant level
- 4Check for grounded or shorted sender lead
- 5Check temperature sender resistance
- 6Check coolant temperature
- 7Check raw water flow
- 8Check raw water impeller
- 9Check heat exchange blockage
- 10Check pressure cap
- 11Check oil level
- 12Check for broken or loose sender lead
- 13Check for pressure sender open
- 14Check sender to control connection
- 15Check heat exchanger for blockage
- 16Check pressure sender resistance
- 17Check control plugs are fully seated
- 18Check sender to control
- 19Check control to plug P13
- 20Check plug P13 to gauges (if equipped)
Related Onan Fault Codes
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