30956 Mercury BEARING, ROLLER - BEARING CARRIER

Table 1
Diagnostic Codes Table    
Description    Conditions which Generate this Code    System Response    
1779-5 Fuel Rail #1 Pressure Valve Solenoid : Current Below Normal     The Electronic Control Module (ECM) detects current that is below normal.
The battery voltage must be above 9 V for 2 seconds.     The code is logged.
If equipped, the warning light will illuminate.
The engine may be shut down.    
1779-6 Fuel Rail #1 Pressure Valve Solenoid : Current Above Normal     The ECM detects current that is above normal.
The battery voltage must be above 9 V for 2 seconds.     Note: The fuel rail pump is installed on the engine at the factory. The fuel rail pump is not a serviceable part. When the fuel rail pump solenoid is energized, fuel is pumped into the fuel rail at very high pressure. When the fuel rail pump solenoid is de-energized, the fuel that is not sent to the fuel rail is returned to the fuel tank.The fuel rail pump solenoid receives an electrical supply from the ECM. Varying the timing of the voltage to the solenoid controls the fuel delivery from the fuel rail pump.The fuel rail pump solenoid forms part of the closed loop control system for the fuel rail pressure with the fuel rail pressure sensor and the ECM. The signal for the fuel rail pressure sensor is processed by the ECM. The ECM compares the measured pressure to the desired fuel rail pressure for the given engine operating conditions.If the fuel rail pump solenoid fails, it is likely that the fuel will not be pumped into the high-pressure fuel rail and engine shutdown or failure to start the engine is expected. No fuel rail pressure can be observed on the status screen of the Caterpillar Electronic Technician (ET).
Illustration 1 g01325680
A typical schematic for the fuel rail pump solenoid
Illustration 2 g01325681
A typical view of the P2 connector (harness side) pin locations. (25) fuel rail pump solenoid signal (26) fuel rail pump solenoid return
Illustration 3 g01344730
A typical view of the P2connector (ECM side) pin locations.Test Step 1. Inspect the Electrical Connectors and the Harness
Electrical shock hazard. The fuel rail pump solenoid uses 63 to 73 volts.
Turn the keyswitch to the OFF position.
Illustration 4 g01325579
Typical engine ECM (1) J2 ECM connector (2) J1 ECM connector
Thoroughly inspect the harness connector P2/J2 and the solenoid connector. Refer to service Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on the wires that are associated with the fuel rail pump solenoid. Refer to Illustration 2.
Check the harness for abrasions and for pinch points from the battery to the ECM. Check the harness for abrasions and for pinch points from the key switch to the ECM.Expected Result:All connectors, pins, and sockets are firmly coupled and/or inserted. The harness is free of corrosion, of abrasion, and of pinch points.Results:
OK - The connectors and the harness are OK. Proceed to Test Step 2.
Not OK - There is a problem with the connectors and/or the harness.Repair: Repair the connectors or the harness and/or replace the connectors or the harness. Ensure that all of the seals are correctly in place and ensure that the connectors are completely coupled.Verify that the repair has eliminated the fault.If applicable, perform a wiggle test by using Cat ET in order to identify intermittent connections.STOPTest Step 2. Check for Active Diagnostic Codes
Connect Cat ET to the diagnostic connector.
Turn the keyswitch to the ON position.
Use Cat ET to verify if any diagnostic codes are active or recently logged. Wait at least 30 seconds for activation of the code.Expected Result:One or more diagnostic codes that are associated with the fuel rail pump solenoid are active or recently logged.
1779-5 Fuel Rail #1 Pressure Valve Solenoid : Current Below Normal
1779-6 Fuel Rail #1 Pressure Valve Solenoid : Current Above NormalResults:
OK - An open circuit diagnostic code -5 is active at this time. Proceed to Test Step 4.
OK - A short circuit diagnostic code -6 is active at this time. Proceed to Test Step 3.
Not OK - No active diagnostic codes or recently logged diagnostic codes are displayed.Repair: The electrical problem may be intermittent. Refer to service Troubleshooting, "Electrical Connectors - Inspect".If applicable, perform a wiggle test by using Cat ET in order to identify intermittent connections.STOPTest Step 3. Disconnect the Connector for the Fuel Rail Pump Solenoid in Order to Create an Open Circuit
Turn the keyswitch to the OFF position.
Disconnect the connector for the fuel rail pump solenoid.
Turn the keyswitch to the ON position.
Use Cat ET to run the "Fuel Pump Solenoid Test", at least two times.Note: The"Fuel Pump Solenoid Test" must be carried out in order to activate the diagnostic codes.
Access the "Active Diagnostic Code" screen on Cat ET. Check for an active open circuit diagnostic code -5 for the fuel rail pump solenoid.
Turn the keyswitch to the OFF position.Expected Result:An open circuit diagnostic code -5 is now active for the fuel rail pump solenoid.Results:
OK - A short circuit diagnostic code -6 was active before disconnecting the connector. An open circuit diagnostic code -5 became active after disconnecting the connector.Repair: There is a problem with the fuel rail pump solenoid. Replace the fuel rail pump. Refer to the Disassembly and Assembly manual. Clear any logged diagnostic codes.STOP
Not OK - There is a short circuit between the connector for the fuel rail pump solenoid and the ECM. There may be a problem with the ECM. Leave the connector disconnected. Proceed to Test Step 5.Test Step 4. Create a Short at the Connector for the Fuel Rail Pump Solenoid
Turn the keyswitch to the OFF position.
Fabricate a jumper wire that is long enough in order to short the terminals of the connector for the fuel rail pump solenoid. Crimp connector pins to each end of the jumper wire.
Disconnect the connector for the fuel rail pump solenoid.
Install the jumper wire between terminal 1 (fuel rail pump solenoid) and terminal 2 (solenoid return) on the harness side of the connector.