COUPLING GP-PUMP 1918924 - Caterpillar

System Operation Description:Use this procedure to troubleshoot any suspected problems with the fuel injectors.This procedure covers the following diagnostic codes:
1-11 Injector Cylinder #1 fault
2-11 Injector Cylinder #2 fault
3-11 Injector Cylinder #3 fault
4-11 Injector Cylinder #4 fault
5-11 Injector Cylinder #5 fault
6-11 Injector Cylinder #6 fault
You have been directed to this procedure from Troubleshooting, "Troubleshooting without a Diagnostic Code".Perform this procedure under conditions that are identical to the conditions that exist when the problem occurs. Typically, problems with the injector solenoid occur when the engine is warmed up and/or when the engine is under vibration (heavy loads).The engine has electronic unit injectors that are mechanically actuated and electronically energized. The Electronic Control Module (ECM) sends a 105 volt pulse to each injector solenoid. The pulse is sent at the proper time and at the correct duration for a given engine load and speed. The solenoid is mounted on top of the fuel injector body. The 105 volt pulse can be individually cut out to aid in troubleshooting misfire problems.If an open is detected in the solenoid circuit, a diagnostic code is generated. The ECM continues to try to fire the injector. If a short is detected, a diagnostic code is generated. The ECM will disable the solenoid circuit. The ECM will then enable the solenoid. If the short circuit remains this sequence of events will be repeated until the problem is corrected.The injector codes must be programmed into the ECM. The injector code is a four digit number (last four digits of the serial number for the injector) that is found on each of the unit injectors. The ECM uses this number to compensate for manufacturing variations between individual injectors. If you replace any of the unit injectors, you must reprogram the code for the new injectors. Also, if you replace the ECM, you must reprogram all of the injector codes. The ECM will generate a 268-02 Check Programable Parameters if the injector codes have not been programmed.For more information, refer to the calibration procedure Troubleshooting, "Injector Code - Calibrate".
Illustration 1 g01147070
Mechanical Electronic Unit Injector (MEUI)
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Schematic for injector solenoids
The connection of any electrical equipment and the disconnection of any electrical equipment may cause an explosion hazard which may result in injury or death. Do not connect any electrical equipment or disconnect any electrical equipment in an explosive atmosphere.
Test Step 1. Inspect Electrical Connectors and Wiring
Electrical shock hazard. The electronic unit injector system uses 90-120 volts.
Turn the keyswitch to the OFF position.
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Left side engine view (typical example) (1) J2/P2 ECM connector
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Left side engine view (typical example) (2) J300/P300 Valve cover connector
Thoroughly inspect connectors (1) and (2). Ensure that the locking tabs for the valve cover connector are securely locked. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 5 g01147016
P2 ECM connector (P2-33) Injector 1 return (P2-34) Injector 2 return (P2-35) Injector 3 return (P2-36) Injector 4 return (P2-44) Injector 1 & 2 supply (P2-45) Injector 3 & 4 supply (P2-46) Injector 5 & 6 supply