- Diagnostic codes and/or event codes
- Electrical connections to the Electronic Control Module (ECM)
- Electronic unit injector connector
- Engine Control Switch (ECS)
- Fuel supply
Note: If the problem only occurs under certain conditions such as high engine speed, full load or engine operating temperature, then perform the test under those operating conditions.
Diagnostic Codes and/or Event Codes
The engine may be shut down due to low pressure levels or other factors. Connect Caterpillar Electronic Technician (ET) and check for active shutdowns or diagnostic codes.
If a shutdown is active, "Injection Disabled" will appear in the third box of any status screen on Cat ET.
An engine shutdown event will appear on a CAN J1939 device if the device is capable of displaying diagnostic codes.
Certain diagnostic codes and/or event codes may cause the engine to shutdown. Connect the Cat ET and check for active codes and/or for logged codes. Troubleshoot any codes that are present before continuing with this procedure.
Electrical Connections to the ECM
- Check the associated wiring for the following conditions: damage, abrasion, corrosion and incorrect attachment .
- J1/P1 and J2/P2 ECM connectors
- J3/P3 Machine Interface Connector
- J44/P44 and J20/P20 Engine Speed/Timing Sensor connectors
- J91/P91Unit Injector Connector
Refer to Troubleshooting, "Electrical Connectors - Inspect".
Note: Aftermarket engine protection devices usually interrupt power to the ECM. Check for correct installation and for operation of aftermarket engine protection devices. It may be necessary to bypass aftermarket devices in order to continue testing.
Electronic Unit Injector Connector
Check the unit injector connectors J91/P91 and associated wiring for the following conditions: damage, abrasion, corrosion and incorrect attachment. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Check the operation of the engine control switch. Monitor the engine control switch on the Cat ET.
Refer to Troubleshooting, "Engine Control Switch (ECS)".
Check for a problem with the fuel supply and verify the fuel pressure. Verify that the fuel pressure sensor is installed. Refer to Testing and Adjusting, "Fuel System" for additional information.