MODULE-ACM 4420591 - Caterpillar

Probable Causes
Diagnostic codes
Event codes
Electrical power supply to the Electronic Control Module (ECM)
Starting aids
Engine shutdown switches
Engine speed/timing
Unit injectors
Oil level
Fuel supply
Combustion problemsRecommended Actions
Diagnostic Codes and Event Codes
Certain diagnostic codes and/or event codes may prevent the engine from starting. Connect the Caterpillar Electronic Technician (ET) and check for active codes and/or for logged codes. Troubleshoot any codes that are present before continuing with this procedure.Electrical Power Supply to the ECM
If the ECM is not receiving battery voltage, the ECM will not operate. Refer to Troubleshooting, "Electrical Power Supply Circuit - Test".Starting Aids (if equipped)
If cold ambient conditions exist, check operation of starting aids. Verify that the air inlet heater is operating correctly. Refer to Troubleshooting, "Air Inlet Heater Circuit - Test".Engine Shutdown Switches
The engine shutdown switches must be in the OFF position in order to start the engine. Use Cat ET to verify the status of the shutdown switches. When an engine shutdown switch is used to shut down the engine, the keyswitch must be turned to the OFF position for at least 15 seconds before restarting the engine.Engine Speed/Timing
Crank the engine and observe the engine speed on the Cat ET status screen. If Cat ET indicates zero rpm, refer to Troubleshooting, "Engine Speed/Timing Sensor Circuit - Test".Note: Upon initial cranking, the status for engine speed may indicate that the engine speed signal is abnormal. This message will be replaced with an engine speed once the ECM is able to calculate a speed from the signal.
Ensure that the timing reference gear is installed correctly. The engine will not start if the gear was installed backward. Check for proper orientation between the crankshaft and camshaft drive gears. Correct the orientation and/or replace the drive gear, if necessary. Refer to Disassembly and Assembly, "Camshaft - Remove and Install".Unit Injectors
Perform the "Injector Solenoid Test" on Cat ET in order to determine if all of the injector solenoids are being energized by the ECM. Refer to Troubleshooting, "Injector Solenoid Circuit - Test" for additional information.Oil Level
Check the engine oil level. If necessary, add oil. Refer to Operation and Maintenance Manual, "Engine Oil Level - Check" for additional information.Note: Engine oil supplies the injection actuation pressure circuit. Proper engine oil level is necessary for fuel injection.Fuel Supply
Visually check the fuel level. Do not rely on the fuel gauge only. If necessary, add fuel. 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 injectorsRefer to Operation and Maintenance Manual, "Fuel System - Prime" for the correct procedure.
Check the fuel lines for the following problems: restrictions, collapsed lines and pinched lines. If problems are found with the fuel lines, repair the lines and/or replace the lines.
Check the fuel tank for foreign objects which may block the fuel supply.
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.
Do not crank the engine continuously