0437801 JOHNSON MOTOR & CABLE ASSY.

Recommended Actions
Do not crank the engine continuously for more than 30 seconds. Allow the starting motor to cool for two minutes before cranking the engine again.
Machine Faults
Make sure that the Machine Security System (if equipped) is not preventing the engine from starting.Resolve any faults on the machine that could prevent the engine from starting.Attempt to start the engine. If the engine will not start, proceed to "Diagnostic Codes and Event Codes".Diagnostic Codes and Event Codes
Certain diagnostic codes and/or event codes may prevent the engine from starting. Connect Cat Electronic Technician (ET) and check for active codes and/or for logged codes. Troubleshoot any active codes that are present before continuing with this procedure.Note: If there are any active diagnostic codes for the machine security system, verify that the lamp for the machine security system is illuminated. If the lamp for the machine security system is illuminated, the machine security system is armed. Deactivate the machine security system and try to start the engine.Note: If a E390 Fuel Filter Restriction is logged and/or active, replace the fuel filters.Fuel that does not meet the recommendations of Operation and Maintenance Manual, SEBU6250, "Caterpillar Machine Fluids Recommendations" may cause premature fuel filter restriction. If the fuel filters are restricted prior to normal service intervals, investigate the quality of the fuel. Use fuel that meets the recommendations of Operation and Maintenance Manual, SEBU6250, "Caterpillar Machine Fluids Recommendations".Note: If a E198 Low Fuel Pressure is logged and/or active, refer to the symptom Troubleshooting, "Fuel Pressure Is Low". Engine Speed/Timing
The diagnostic codes for the engine speed/timing are disabled during engine cranking. The status of the engine speed/timing sensor's can be viewed on the "No Start" screen with Cat ET when the engine is cranking. The diagnostics for the engine speed/timing will be enabled after the engine is running.If a speed sensor is not detected, refer to the circuit test Troubleshooting, "Speed/Timing - Test".Make sure that any repairs have eliminated the problem.Electrical Connectors
Check for correct installation of the J1/P1 and J2/P2 ECM connectors. Check for correct installation of all other applicable connectors. Refer to service Troubleshooting, "Electrical Connectors - Inspect".Air Intake and Exhaust System
Check the air filter restriction indicator, if equipped. Clean plugged air filters or replace plugged air filters. Refer to the Operation and Maintenance Manual.
Check the air inlet and exhaust system for restrictions and/or leaks. Refer to Systems Operation/Testing and Adjusting.Air Inlet Heater
Note: A faulty air inlet heater will only affect engine starting when the ambient temperature is below 10 °C (50 °F).
Check the operation of the air inlet heater. Refer to Systems Operation/Testing and Adjusting.
If necessary, replace the air inlet heater. Refer to Disassembly and Assembly.Low Pressure Fuel System
Visually check the fuel level. Do not rely on the fuel gauge only. If necessary, add fuel. If the engine has been run out of fuel, purge the air from the fuel system. Prime the fuel system.
Ensure that the fuel supply valve (if equipped) is in the full OPEN position.
Contact with high pressure fuel may cause fluid penetration and burn hazards. High pressure fuel spray may cause a fire hazard. Failure to follow these inspection, maintenance and service instructions may cause personal injury or death.
Do not loosen any high pressure fuel lines when the engine is running. The high pressure in the fuel lines can cause personal injury or death. Wait 60 seconds after the engine has stopped to allow pressure to purge before any service or repair is performed on the engine fuel lines.
Check the fuel lines for the following problems: restrictions, collapsed lines, pinched lines and loose connections. If problems are found with the low-pressure fuel lines, repair the lines and/or replace the lines. If the high-pressure fuel lines have a leak, the high-pressure fuel lines must be replaced. Refer to the Disassembly and Assembly manual.
Do not crank the engine continuously for more than 30 seconds. Allow the starting motor to cool for two minutes before cranking the engine again.
Prime the fuel system if any of the following procedures have been performed:
Replacement of the fuel filters
Service on the low-pressure fuel supply circuit
Replacement of unit injectorsNote: A sight glass in the low-pressure supply line is helpful in diagnosing air in the fuel. Refer to Testing and Adjusting.
Check for air in the fuel system. Refer to Testing and Adjusting, "Air in Fuel - Test". Ensure that the fuel system has been primed. Attempt to start the engine. If the engine will not start, continue with this procedure.
Check the fuel tank for foreign objects which may block the fuel supply.
Check the fuel filters.
Check the diesel fuel for contamination. For acceptable quality, refer to Operation and Maintenance Manual, SEBU6250, "Caterpillar Machine Fluids Recommendations".
Cold weather adversely affects the characteristics of the fuel. Refer to the Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold-weather operation.
Attempt to start the engine. If the engine will not start, continue with this procedure.
Check the flow of fuel through the transfer pump. If the flow is less than 250 mL (8.5 oz) per minute at 150 rpm, replace the pump. For instructions on removal and installation of the fuel transfer pump, refer to the engine Disassembly and Assembly manual. Make sure that the engine is primed. Attempt to start the engine. If the engine will not start, continue with this procedure.High Pressure Fuel System
Escaping fluid under pressure, even a pinhole size leak, can penetrate body tissue, causing serious injury, and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.