CONTACT ASSEM. 3Y4425 - Caterpillar

Table 1
Diagnostic Trouble Codes    
J1939 Code    CDL Code    Code Description    Comments    
168-2     168-2     Battery Potential / Power Input #1 : Erratic, Intermittent, or Incorrect     This code indicates that the battery circuit to the ECM is intermittent.    
168-3     168-3     Battery Potential / Power Input #1 : Voltage Above Normal     The ECM detects voltage that is above the acceptable value.    
168-4     168-4     Battery Potential / Power Input 1 : Voltage Below Normal     The ECM detects voltage that is below the acceptable value.    
Follow the troubleshooting procedure in order to identify the root cause of the fault.    
Illustration 1 g03366300
Typical example of the schematic for the electrical power supply circuit
Illustration 2 g03366309
View of the pin locations on the P1 connector for the ignition keyswitch and battery supply circuit (1) Battery ground (2) Battery ground (3) Battery ground (7) Battery+ (8) Battery+ (9) Battery ground (10) Battery ground (15) Battery+ (16) Battery+ (40) Ignition keyswitch
Table 2
Troubleshooting Test Steps     Value     Results    
1. Determine the Diagnostic Code
A. Establish communication between the electronic service tool and the ECM . Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Start the engine. Run the engine until the engine is at normal operating temperature.
C. Observe the "Active Diagnostic" screen on the electronic service tool. Wait at least 30 seconds so that any codes may become active.
   
Diagnostic code    
Result: One of the diagnostic codes listed in Table 1 is active.
Proceed to Test Step 2.
Result: The electronic service tool will not communicate with the ECM.
Repair: Refer to Troubleshooting, "Electronic Service Tool Does Not Communicate".
   
2. Check the Charging Circuit
A. Check the charging circuit. Refer to Systems Operation, Testing and Adjusting, "Charging System - Test".
   
Charging circuit
   
Result: The charging system is OK.
Proceed to Test Step 3.
Result: The charging system is not OK.
Repair: There is a fault in the charging system. Make the necessary repairs.
Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.
   
3. Load Test the Batteries
A. Use a suitable battery load tester to test the batteries. Refer to Systems Operation, Testing and Adjusting, "Battery - Test" for the correct procedure.
   
Load test
   
Result: The batteries pass the load test.
Proceed to Test Step 4.
Result: The batteries do not pass the load test.
Repair: Recharge or replace the faulty batteries.
Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.
   
4. Inspect Electrical Connectors and Wiring
A. Ensure that the battery disconnect switch is in the CLOSED position.
B. Thoroughly inspect all connectors associated with the electrical power supplies.
C. Check all fuses.
D. Perform a 45 N (10 lb) pull test on each of the wires in the connectors associated with the electrical power supplies.
E. Check all of the wiring associated with the electrical power supplies for abrasions and pinch points.
F. Verify that the "System Operating Voltage Configuration" is correctly configured in