84105M Mariner LEVER SEE NOTE #4

Table 1
J1939 Codes and Description CDL Codes and Description Comments
931-5
Engine Fuel Supply Pump Actuator : Current Below Normal 1627-5
Fuel Pump Relay : Current Below Normal This code indicates that there is a problem with the engine fuel priming pump relay and /or electrical circuit.
931-6
Engine Fuel Supply Pump Actuator : Current Above Normal 1627-6
Fuel Pump Relay : Current Above Normal This code indicates that there is a problem with the engine fuel priming pump relay and /or electrical circuit.
7102-5
Engine Fuel Filter Circulating Pump : Current Below Normal 4550-5
Electric Fuel Transfer Pump Relay : Current Below Normal This code indicates that there is an issue with the fuel priming solenoid valve relay and/or the electrical circuit.
7102–6
Engine Fuel Filter Circulating Pump : Current Above Normal 4550-6
Electric Fuel Transfer Pump Relay : Current Above Normal This code indicates that there is an issue with the fuel priming solenoid valve relay and/or the electrical circuit. An electric off-engine boost pump supplies fuel from the tank to the on-engine mechanical fuel transfer pump. Fuel is drawn from the tank through a strainer to protect the boost pump from debris. Fuel then passes through the primary filters. The amount of filtered fuel required by the on-engine fuel system flows to the mechanical fuel transfer pump and the rest recirculates through the priming loop check valve and priming solenoid valve back to the boost pump inlet. Pressurized fuel from the on-engine mechanical fuel transfer pump passes through the secondary filters and supplies the required fuel flow to the high-pressure fuel pump, the starting priority valve, the low-pressure fuel system regulator, and the injector cooling circuit. The high-pressure pump supplies the required amount of burned fuel to the injectors. The high-pressure pump and injector cooling flows return back to tank. Refer to System Operation, Fuel System Operation for more detail.
Table 2
Component Electrical Checkout
Engine Fuel Supply Pump Actuator Fuel Pump Relay Command Override
Priming Solenoid Valve Electric Fuel Transfer Pump Relay Override
Illustration 1 g06307459Probable Causes
Codes
Open circuit
Short circuitRecommended Actions
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 931-5or 1627-5code is active or logged.
Proceed to Test Step 2.
Result: A 931-6or 1627-6 code is active or logged.
Proceed to Test Step 3.
Result: A 7102-5 or 4550-5 code is active or logged.
Proceed to Test Step 4.
Result: A 7102-6 or 4550-6 code is active or logged.
Proceed to Test Step 5.
2. Check the Wiring for an Open Circuit
A. Verify that the wiring harness connector is free of debris, free of corrosion, and securely connected.
B. Disconnect the solenoid from the engine harness.
C. Connect a jumper wire between the terminals of the harness connector for the suspect coil. The coil is replaced with a short circuit.
D. Perform the appropriate electrical checkout.
Open Circuit
Results: 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 may be a problem with a connector.
Repair: Repair or replace the appropriate wiring harness.
Verify that the repair eliminated the problem.
Results: A -6 code is activated during the electrical checkout. The ECM detected the jumper wire. There is a problem with the solenoid.
Repair: Replace the solenoid.
Verify that the repair eliminated the problem.
3. Check the Wiring for a Short Circuit
A. Verify that the harness connector is free of debris, free of corrosion, and securely connected.
B. Disconnect the Clean Fuel Module (CFM) resistor from the engine wiring harness connector.
C. Perform the appropriate electrical checkout.
Short Circuit
Results: A -6 code became active during the electrical checkout. The ECM did not detect the open circuit. There is a short circuit in the wiring between the coil and the ECM connector. There may be a problem with a connector.
Repair: Repair or replace the appropriate wiring harness.
Verify that the repair eliminated the problem.
Results: A -5 code became active during the electrical checkout. The ECM detected the open circuit. The wiring is OK. The coil has a short circuit.
Repair: Replace the solenoid.
Verify that the repair eliminated the problem.
4. Check the Wiring Harness for an Open Circuit
A. Verify that the harness connector is free of debris, free of corrosion, and securely connected.
B. Disconnect the Priming Solenoid Valve Relay from the engine harness connector.
C. Connect a jumper wire between terminal 2 and terminal 5 on the Priming Solenoid Valve Relay wiring harness connector.
D. Perform the appropriate electrical checkout.
Open Circuit
Result: A - 5 code came active during the electrical checkout. The ECM did not detect the jumper wire. There is an open circuit in the wiring between the coil and the ECM connector. There may be a problem with the connector.
Repair: Repair or replace the appropriate wiring harness.
Verify that the repair eliminated the problem.
Result: A - 6 code came active during the electrical checkout. The ECM detected the jumper wire. There is a problem with the Priming Solenoid Valve Relay.
Repair: Replace the Priming Solenoid Valve Relay.
Verify that the repair eliminated the problem.
5. Check the Wiring Harness for a Short Circuit
A. Verify that the harness connector is free of debris, free of corrosion, and securely connected.
B. Disconnect the Priming Solenoid Valve Relay from the engine wiring harness connector.
C. Perform the appropriate electrical checkout.
Short circuit
Result: A - 6 code came active during the electrical checkout. There is a short circuit in the wiring between the coil and the ECM connector. There may be a problem with the connector.
Repair: Repair the appropriate harness wiring or replace the appropriate wiring harness.
Verify that the repair eliminated the problem.
Result: A - 5 code came active during the electrical checkout. There is a problem with the CFM resistor.
Repair: Replace the Priming Solenoid Valve Relay.
Verify that the repair eliminated the problem.
If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).