1201
What This Code Means
External display board is not able to communicate with main board; Main board does not see communication from display board; Overcrank; Low to no fuel pressure while cranking; Overspeed (Over 72 Hz for three seconds); Throttle stuck open; Overspeed (Over 75 Hz for one second); Total loss of control; High temperature (Coolant temp greater than 246 ºF (119 ºC) for 1 second); Overcrank alarm; Overspeed (Over 72 Hz for three seconds with the throttle stuck open); Overspeed (Over 75 Hz for one second with the throttle stuck open, total loss of control); Low oil pressure while running
Possible Causes
- •Air Flow Impeded / Flow Issue
- •Air flow impeded
- •Check the oil level
- •Engine/Starter Problem
- •Flow issue
- •Internal Harness Loop Broken (internal to the display board)
- •Internal harness connecting external display board to main board has become disconnected
- •Internal harness loop broken (external display board)
- •Low to no fuel pressure while cranking
- •No Fuel Pressure
- •Stuck throttle
Suggested Actions
- 1Check coolant sensor circuit for proper operation
- 2Check coolant sensor circuit for proper operation.
- 3Check the inlet/outlet for debris
- 4Check the inlet/outlet for debris.
- 5Clear any faults in the controller before proceeding with any running diagnostic steps
- 6Clear any faults in the controller before proceeding with diagnostic steps
- 7Follow procedure in Appendix B
- 8Fuel pressure has to be measured as low for at least 1200 ms before the overcrank alarm is set.
- 9Test 12 – Check stepper motor control
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