PLUG 4N4957 - Caterpillar

Table 1
Troubleshooting Test Steps Values Results
1. Check For Diagnostic Trouble Codes (DTCs)
DTCs are not present
OK - No DTCs are present.
STOP
Not OK - A DTC is present.
Go to Step 2.
2. Check Connections
A. Inspect the circuit harness connectors.
Connections are:
*Clean
*Secure
*In good condition
OK - Connections are good.
Go to Step 3.
Not OK - A connection problem exists.
Repair:
Repair or replace the harness.
Verify that the problem is corrected.
STOP
3. Check For Power at the ECM
A. Check for system power at the VIMS ECM.
System power is present
OK - There is system power at the ECM.
Go to Step 4.
Not OK - System power is not at the ECM.
Repair:
Correct the power problem.
Verify that the problem is corrected.
STOP
4. Check the Hardware
A. Visually inspect the hardware.
Look for apparent damage.
B. Verify the hardware and the software part numbers(1).
*There is no apparent damage
*Part numbers are correct
OK - Hardware checks OK.
Go to Step 5.
Not OK - Hardware is damaged.
Repair:
Replace the damaged hardware.
STOP
Not OK - All part numbers are not correct.
Repair:
A. An ECM has the wrong part number:
*Replace the ECM(2).
*Flash the correct software(3).
B. An ECM has the incorrect flash software installed:
*Flash the correct software(3).
STOP
5. Verify VIMS With Cat ET
A. Connect Cat ET to the machine.
ECM is available
OK - The ECM is available.
Go to Step 6.
Not OK - The ECM is available.
Repair:
A. Troubleshoot the ECM harness and connections.
B. Correct any discrepancies found.
STOP
6. "Machine Run Status" Is Correct
A. In Cat ET, go to "Status Parameters".
B. Verify that the alternator running input displays "Engine Off".
C. Start the machine.
D. Verify that status.
*"Alternator Running Input" changes to " Engine Running"
*"Keyswitch Status" is on
OK - The Cat ET "Status" screen changes from "Engine Off" to "Engine Running" when the machine is started. The "Keyswitch Status" is on.
STOP
Not OK - On the Cat ET screen, the status did not change from "Engine Off" to "Engine Running".
Repair:
*Check the alternator R-Terminal wiring.
*Check the power wire.
*Recheck the problem.
If the problem is not corrected, replace the VIMS ECM(2).
STOP
(1) Consult your Cat® Dealer for the correct part numbers
(2) See Testing and Adjusting, "ECM - Replace"
(3) See Troubleshooting, "ECM Software - Install"