DIAPHRAGM 5K5941 - Caterpillar

The probable root causes are listed below:
Electrical power supply
Low fuel level
Fuel supply
Starting aids (if applicable)
Cranking speed
Shutdown switch
Active engine shutdown
Electrical connectors
Circuit breakers
Personality module
Engine speed/timing sensor
Injector solenoid
Air shutoff (if applicable)Perform the following checks:
Measure the voltage at the connector of the Electronic Control Module (ECM). If the ECM is not receiving battery voltage, the ECM will not power up. Refer to the diagnostic functional test Troubleshooting, "Electrical Power Supply".
Visually check the fuel level. If necessary, add fuel. Ensure the proper operation of the jacket water heater. Repair the jacket water heater and/or replace the jacket water heater. Check for the presence of solidified fuel (wax).
Check the fuel system. Check fuel lines for the following problems: restrictions, collapse, pinched line and loose fittings. Repair the lines and/or replace the lines.
Check the fuel tank for foreign objects which may block the fuel supply. Check for air in the low pressure fuel supply system after you perform the following procedures:
Replacing the fuel filters
Working on the low pressure fuel supply circuit
Replacing fuel injectors
Purge air from the low pressure fuel supply circuit with the hand priming pump and by cranking the engine in 30 second cycles. After you crank the engine, stop for two minutes. This will allow the starting motor to cool. Loosen the vent plug for the fuel return line. The plug is located on the rear upper left side of the engine block. Hand prime the engine again if air in fuel continues. A sight glass in the low pressure supply line is helpful in diagnosing air in the fuel.
Check fuel quality. In temperatures below 0 °C (32 °F), check for solidified fuel (wax). Refer to Special Publication, SEBD0717, "Diesel Fuels And Your Engine". Check the fuel pressure while the engine is cranking. Check the fuel pressure at the filter. If the pressure is low, check for plugged fuel filters. If the fuel pressure is still low, check the following items: fuel transfer pump, fuel transfer pump coupling and fuel pressure regulating valve.
If equipped, check the operation of the ether starting aids. Replace the ether canister if the ether is low. Refer to the diagnostic functional test Troubleshooting, "Ether Injection System".
Check the cranking speed of the starter.
The shutdown switch should be in the OFF position. Connect the Caterpillar Electronic Technician (ET). Use Cat ET in order to verify the status of the shutdown switch. If the Cat ET will not communicate with the ECM, refer to the diagnostic procedure Troubleshooting, "Electronic Service Tool Will Not Communicate with ECM". When a shutdown occurs, the keyswitch must be turned to the OFF position. The keyswitch must then be turned to the ON position before the engine will start.
Use Cat ET to determine if any active shutdowns are present. If a Shutdown is "ACTIVE", determine the reason. After you correct the problem, turn the keyswitch to the OFF position for at least 15 seconds before you try to restart the engine.
Check for correct installation of the following components: ECM connectors J1/P1 and J2/P2, customer connector, connector