GOVERNOR GP-UNIT INJECTOR 1421420 - Caterpillar

Table 1
J1939 Code and Description CDL Code and Description Comments
4336-5
Aftertreatment #1 SCR Dosing Air Assist Valve : Current Below Normal 3094-5
Aftertreatment #1 SCR Dosing Air Assist Signal : Current Below Normal This code indicates that there is a problem with the Dosing Air Assist Valve and/or the electrical circuit for the Dosing Air Assist Valve.
4336-6
Aftertreatment #1 SCR Dosing Air Assist Valve : Current Above Normal 3094-6
Aftertreatment #1 SCR Dosing Air Assist Signal : Current Above Normal This code indicates that there is a problem with the Dosing Air Assist Valve and/or the electrical circuit for the Dosing Air Assist Valve.
4376-5
Aftertreatment #1 DEF Return Valve : Current Below Normal 3862-5
Aftertreatment #1 Diesel Exhaust Fluid Return Valve Solenoid : Current Below Normal This code indicates that there is a problem with the Diesel Exhaust Fluid (DEF) Return Valve and/or the electrical circuit for the DEF Return Valve.
4376-6
Aftertreatment #1 DEF Return Valve : Current Above Normal 3862-6
Aftertreatment #1 Diesel Exhaust Fluid Return Valve Solenoid : Current Above Normal This code indicates that there is a problem with the DEF Return Valve and/or the electrical circuit for the DEF Return Valve.
5434-5
Tank Fill Valve : Current Below Normal N/A This code indicates that there is a problem with the DEF Tank Fill Valve and/or the electrical circuit for the DEF Tank Fill Valve.
5434-6
Tank Fill Valve : Current Above Normal N/A This code indicates that there is a problem with the DEF Tank Fill Valve and/or the electrical circuit for the DEF Tank Fill Valve.
7416-5
Aftertreatment #1 DEF Pump Power Relay : Current Below Normal N/A This code indicates that there is a problem with the DEF pump power relay and/or the electrical circuit for the DEF pump power relay.
7416-6
Aftertreatment #1 DEF Pump Power Relay : Current Above Normal N/A This code indicates that there is a problem with the DEF pump power relay and/or the electrical circuit for the DEF pump power relay. Electrical Checkouts on the Cat® Electronic Technician (ET)
Table 2
Component Electrical Checkout
Dosing Air Assist Valve DEF Dosing Air Assist Valve Command Override
DEF Return Valve DEF Return Valve Override
DEF Tank Fill Valve DEF Tank Fill Valve Override
DEF Pump Power Relay DEF Pump Power Relay Override
Illustration 1 g06325963
Table 3
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Determine if a code is active or logged.
Codes
Result: A -5 code is active or logged.
Proceed to Test Step 2.
Result: A -6 code is active or logged.
Proceed to Test Step 3.
2. Check the Wiring for an Open Circuit
A. Verify that the harness connector is free of debris, free of corrosion and securely connected.
B. Disconnect the solenoid from the harness.
C. Install a jumper wire between the terminals of the harness connector for the affected coil. The coil is replaced with a short circuit.
Create a Short
Result: A -5 code became active during the electrical checkout. The Electronic Control Module (ECM) did not detect the jumper wire. There is an open circuit in the wiring between the coil and the ECM connector. There