VARISTOR ASSEM. 3N7776 - Caterpillar

System Operation Description:While the engine is running, if engine speed suddenly becomes zero and the Auto Start/Stop function block has not initiated a shutdown, an "UNEXPECTED ENGINE SHUTDOWN" event will be activated.The EMCP 4 performs the following using an independent engine speed sensor that is dedicated to EMCP 4 use only
Determines the engine speed, in rpm, from the Magnetic Pickup (Engine Speed Sensor) input pins
Detects diagnostics on the sensor
Annunciates an engine over/under speed conditionConditions Which Generate This Code:While the engine is running, if engine speed suddenly becomes zero and the Auto Start/Stop function block has not initiated a shutdown, an "UNEXPECTED ENGINE SHUTDOWN" event will be activated.Test Step 1. TALK TO THE OPERATOR
Determine the conditions that caused the unexpected shutdown. Expected Result:A unexpected shutdown was caused by an occurrence known to the operator and the operator would like to put the genset back into service.Results:
OK - The operator can determine the cause for the "UNEXPECTED ENGINE SHUTDOWN", the condition has been repaired and the operator wants to put the genset back into service.Repair: Reset the genset. Resume normal operation and verify that the problem has been corrected.STOP
NOT OK - The "UNEXPECTED ENGINE SHUTDOWN" was not caused by a occurrence known to the operator. Proceed to Test Step 2Test Step 2. CHECK FOR OTHER DIAGNOSTIC CODES.
Check for active diagnostic codes on the Engine ECM and the EMCP 4. If any codes are present, correct the diagnostic codes first. Expected Result:No other diagnostic codes or indicators are active.Results:
OK - No other diagnostic codes or indicators are active.Repair: Refer to the engine Troubleshooting manual for more information on engine unexpected engine shutdowns for your particular genset.STOP
NOT OK - Another diagnostic code is active or an indicator is active.Repair: Exit this procedure. Troubleshoot the active code or indicator. Resume normal operation and verify that the problem has been corrected.STOP