ELBOW 5P3426 - Caterpillar

Conditions Which Generate This Code:
Illustration 1 g00596717
The EMCP II has a sensor supply voltage of 8 DCV from the GSC that powers the engine sensors. The sensors that are displayed in illustration 1 may vary. The sensors may vary according to the engine. See table 1 in order to determine the sensors on your engine.
Table 1
Sensor     MUI Engines     EUI Engines    
Coolant Temperature     Yes     No    
Oil Pressure     Yes     No    
Coolant Loss     Yes     Yes    The sensor power supply functions whenever power is applied to the GSC.The GSC is usually programmed in the factory. The GSC handles a diagnostic code that is associated with the sensor power supply as an alarm fault. P04 = 0. If the GSC is programmed to shutdown, P04 is equal to 1 for a problem with the sensor power supply. It is not necessary to press the "Alarm Codes" key in order to view the CID 0269 FMI 04. The CID 0269 FMI 04 is automatically shown on the upper display.Diagnostic codes are created when the harness connector is disconnected from the GSC during these troubleshooting procedures. Clear these created diagnostic codes after the particular problem is corrected and the particular diagnostic code is cleared. The possible cause of a CID 0269 FMI 04 occurs when the voltage of the sensor supply is less than 7.5 DCV.Begin performing these procedures only when CID 0269 FMI 04 is active and the "DIAG" indicator is FLASHING on the upper display. The GSC treats a CID 0269 FMI 04 as an alarm fault. Active alarm faults are shown on the upper display when the "Alarm Codes" key is pressed and the engine control switch (ECS) is in any position except the OFF/RESET position. For an inactive diagnostic code, the problem may be intermittent. To troubleshoot an inactive diagnostic code, use the preceding system schematic and see Testing And Adjusting, "Electrical Connector - Inspect". Clear the diagnostic code from the fault log after the troubleshooting procedure is completed.Test Step 1. CHECK THE GSC.
Turn the ECS to OFF/RESET.
Disconnect the harness from the GSC.
Turn the ECS to STOP.
Press the "Alarm Codes" key.
Observe the upper display for the CID 0269 FMI 04. If the diagnostic code is displayed then the problem is active.Expected Result:The CID 0269 FMI 04 should NOT be showing on the upper display.Results:
OK - The GSC is functioning properly. Therefore, the engine harness or a sensor has failed. Proceed to test step 2.
NOT OK - The GSC has failed. Repair: Replace the GSC. See Testing And Adjusting, "EMCP Electronic Control (Generator Set) - Replace". Stop.Test Step 2. VERIFY THE TYPE OF ENGINE
Select the appropriate engine in order to determine the proper test sequence.Expected Result:Select the appropriate engine.Results:
MUI - Test the engine sensor circuit for MUI engines. Proceed to test step 3.
EUI - Test the engine sensor circuit for EUI engines. Proceed to test step 6.Test Step 3. CHECK THE COOLANT LOSS SENSOR
Turn the ECS to OFF/RESET.
Reconnect the