0316657 JOHNSON SCREW, Cover mounting, front port

Table 1
Diagnostic Codes Table    
Description    Conditions which Generate this Code    System Response    
323-3 Engine Shutdown Lamp : Voltage Above Normal     While the engine fault output is activated, the Electronic Control Module (ECM) detects a short circuit or a short to the +Battery in the circuit that is for the "Engine Fault" indicator.     The code is logged.
The alarm output is activated.
The output driver automatically resets and the output driver continues to try to activate the circuit component.    
324-3 Warning Lamp (Action) : Voltage Above Normal     While the action lamp output is activated, the ECM detects a short circuit or a short to the +Battery in the circuit that is for the "Action Alarm" indicator.    
443-3 Crank Terminate Relay : Voltage Above Normal     While the crank terminate output is activated, the ECM detects a short circuit or a short to the +Battery in the circuit that is for the "Crank Terminate" indicator.    
445-3 Run Relay : Voltage Above Normal     While the output for the engine running output is activated, the ECM detects a short circuit or a short to the +Battery in the circuit that is for the "Engine Running" indicator.    The master ECM has four outputs that are used to indicate the status of engine operation: engine running output, crank terminate output, action alarm output and engine fault output. These outputs can be used to energize indicator lamps or the outputs can be used to interface with other controls.The master ECM opens an internal circuit in order to turn off the output. The master ECM closes the circuit in order to turn on the output. When the circuit is closed and the output is on, the ECM allows a maximum current of 0.3 amperes to flow through the circuit to a ground circuit that is inside the ECM.If excessive current flows through the circuit, a diagnostic code is generated. A short circuit to the +Battery side will also activate a diagnostic code. Note: These circuits do not sink enough current for illumination of standard incandescent lamps. If a lamp is burned out, replace the lamp with the correct part number that is specified in the engine's Parts Manual.The following information defines the ECM outputs that are for the indicator lamps:"Engine Running Output" - This output indicates that the engine is in the "Run" status. The engine will start soon or the engine is running."Crank Terminate Output" - This output indicates that the engine rpm is greater than the programmed engine speed that is required for disengagement of the starting motor."Action Alarm Output" - This is the alarm output. This output indicates that the master ECM has detected an electrical problem or an abnormal operating condition."Engine Fault Output" - This is the shutdown output. This output indicates that a potentially damaging operating condition was detected by the master ECM. The master ECM has shut down the engine.Note: While any of these output drivers are on, a short circuit to a positive voltage source or excessive current through the circuit will cause a diagnostic code to become activated. The ECM cannot diagnose the circuit while the output driver is off.A 323-3 or 324-3 can only be generated if a shutdown condition or an alarm condition is active. Failure to correct a serious condition with the engine can result in engine damage.Use Caterpillar Electronic Technician (ET) to determine if an event code or a diagnostic code that corresponds to the 323-3 or 324-3 diagnostic code is active. You must troubleshoot other event codes and/or diagnostic codes before you troubleshoot a 323-3 or 324-3 diagnostic code. Refer to Troubleshooting, "Event Codes" or Troubleshooting, "Diagnostic Trouble Codes" for the correct test procedure.The most likely causes of a diagnostic code for a status indicator is a poor electrical connection, a problem in a wiring harness, or the lamp. The next likely cause is a problem with the lamp socket assembly. The least likely cause is a problem with the ECM.Logged diagnostic codes provide a historical record. Before you begin this procedure, use Cat ET to print the logged codes to a file.The troubleshooting procedure may generate additional diagnostic codes. Correct the cause of the original diagnostic code before continuing. Clear the diagnostic codes after the problem is resolved.
Illustration 1 g01585354
Schematic for the status indicatorsTest Step 1. Inspect the Electrical Connectors and the WiringNote: Some indicators may obtain the status of the engine via a data link. If the status indicator that is suspect is not directly controlled by the outputs at the ECM, do not proceed with this test.
Set the engine control to the OFF/RESET position. Remove the electrical power from the engine.
Illustration 2 g01423505
Terminal box (1) J2/P2 ECM connectors (2) J5/P5 customer connectors (3) P10 connector for the harness to the optional control panel
Thoroughly inspect connectors (1), (2), and (3). Also, thoroughly inspect the connections at the terminal strip at the optional display panel. Ensure that the connections are clean and tight. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 3 g01423887
Harness side of the P2 connector (P2-28) Engine running output (P2-29) Crank terminate output (P2-30) Engine fault output (P2-31) Action alarm output
Illustration 4 g01423888
Harness side of the P5 connector (P5-7) Crank terminate output (P5-8) Action alarm output (P5-9) Engine fault output (P5-19) Engine running output
Illustration 5 g01423892
Harness side of the P10 connector (P10-C) Crank terminate output (P10-H) Action alarm output (P10-P) Engine fault output (P10-Z) Engine running output
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the engine starting system.
Check the allen head screw for each of the ECM connectors and for the customer connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the wiring harnesses for abrasion, for corrosion and for pinch points.Expected Result:All connectors, pins and sockets are completely coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and wiring appear to be OK. Proceed