HEAD 6J7890 - Caterpillar

Table 1
J1939 Code and Description CDL Code and Description Comments
1076-5
Engine Fuel Injection Pump Fuel Control Valve : Current Below Normal 18-5
Fuel Control Valve : Current Below Normal The ECM detects signal voltage that is not in the acceptable range.
The code is logged.
1076-6
Engine Fuel Injection Pump Fuel Control Valve : Current Above Normal 18-6
Fuel Control Valve : Current Above Normal The ECM detects signal voltage that is not in the acceptable range.
The code is logged.
Table 2
Required Tooling
Qty Part Number Part Name
1 372-5260 Test Lead Tool Group Note: The automatic cylinder cutout test is disabled while any of these codes are active.
Table 3
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Establish communication between Cat® Electronic Technician (ET) and the ECM. Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Download the "Warranty Report" from the ECM before performing any troubleshooting or clearing diagnostic trouble codes.
C. Look for an active or logged -5 code or -6 code.
Codes
Result: There is an active or there is a logged -5 code
Proceed to Test Step 2.
Result: There is an active or there is a logged -6 code.
Proceed to Test Step 3.
2. Check the Wiring for an Open Circuit
A. Turn the keyswitch to OFF.
B. Verify that the harness connector is free of debris, free of corrosion, and securely connected.
C. Disconnect the fuel pump solenoid from the harness.
D. Connect a jumper wire between terminals 1 and 2 of the harness connector for the solenoid. The solenoid coil is replaced with a short circuit.
Note: A 372-5260 Test Lead Tool Group is required for completing this procedure. Connect two 398-4985 Probes to the fuel pump solenoid harness connector. The connectors must be used to prevent damage to the fuel pump solenoid connector.
E. Turn the keyswitch to ON. Do not start the engine.
F. Connect to Cat ET. Check for an active or logged -5 or -6 code.
Short Circuit
Result: A -5 code became active. The ECM did not detect the jumper wire. There is an open circuit in the wiring between the solenoid and the ECM connector. There may be a problem with a connector.
Repair: Repair or replace the connectors and/or wiring as