0388684 JOHNSON FUEL PUMP ASSY.

Illustration 1 g01193921Test Step 1. Check for Connector Damage.
Turn the circuit breaker for the battery to the OFF position.
Turn the ECS to the OFF/RESET position.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. Inspect all of the other connectors. Refer to the diagnostic functional test Troubleshooting, "Inspecting Electrical Connectors" for details.
Check the allen head screw on each ECM connector for the proper torque. Refer to Troubleshooting, "Inspecting Electrical Connectors" for the correct torque values.
Check the ECM connector (allen head screw) for the proper torque of 6 1 N m (53 9 lb in).
Check the harness and the wiring for abrasion and for pinch points. Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The connectors and wiring are OK. Proceed to Test Step 2.
Not OK - The connectors and/or wiring are not OK.Repair: Repair the connectors or wiring and/or replace the connectors or wiring.STOPTest Step 2. Check the Resistance of the Prelube Pressure Switch at the ECM.
Turn the ECS to the OFF/RESET position.
Disconnect ECM connector J1/P1.
Ensure that the prelube override switch is not activated.
Measure the resistance between the prelube pressure switch P1-66 and the digital return P1-5.
Reconnect the ECM connector P1. Expected Result:The resistance is greater than 20000 Ohms.Note: If the engine has been running, the residual oil pressure may be high enough to activate the prelube pressure switch. If the residual oil pressure is high, the resistance would be less than 5 Ohms.Results:
OK - The resistance is greater than 20000 Ohms. The prelube pressure switch is not active. Proceed to Test Step 4.
Not OK - The resistance is less than 20000 Ohms. The prelube pressure switch is active. Verify that the engine does not have a residual oil pressure that is high enough to activate the switch. If there is no residual oil pressure, the switch is not operating correctly or there is a problem with the wiring. Proceed to Test Step 3.Test Step 3. Measure the Resistance of the Prelube Pressure Switch at the Prelube Pressure Switch.
Turn the ECS to the OFF/RESET position.
Disconnect the wires from the terminals of the prelube pressure switch.
Measure the resistance between the terminals of the prelube pressure switch. Expected Result:The resistance is greater than 20000 Ohms.Results:
OK - The resistance is greater than 20000 Ohms. There is a problem with the wiring between ECM connector J1/P1 and the switch.Repair: Repair the connectors or wiring and/or replace the connectors or wiring.STOP
Not OK - The resistance is less than 20000 Ohms. There is a problem with the prelube pressure switch.Repair: Temporarily replace the prelube pressure switch with a new switch. If the problem is no longer present, reinstall the old switch. If the problem returns, replace the switch.STOPTest Step 4. Check the Status of the ECS and the Prelube Pressure Switch on the Caterpillar Electronic Technician (ET).
Connect Cat ET to the service tool connector.
Turn the ECS to the STOP position.
Use Cat ET and view the following parameters: Engine Prelube and Ignition Switch.
Go to the diagnostic test in the diagnostic section on CAT ET. Activate the override for the engine prelube.
View the parameters for the prelube pressure switch and the ignition switch.
Disable the override for the engine prelube. Expected Result:When the ECS is in the STOP position, the engine prelube displays "OFF" and the ignition switch displays "STOP". When the override for the engine prelube is activated, the engine prelube displays "ON" and the ignition switch displays "STOP".Results:
OK - The parameters are correct. Proceed to Test Step 5.
Not OK - The status of the ignition switch does not display "STOP".Repair: Perform the diagnostic functional test Troubleshooting, "Engine Control Switch (ECS)".STOP
Prelube Disabled - The prelube function is disabled. The engine prelube duration is set to zero.Repair: The cycle time of the engine prelube must be greater than zero for the prelube function to work.STOPTest Step 5. Check for Output Voltage from the "PPR1" Relay at the Connector P-C1 to the Prelube Motor.
Turn the ECS to the OFF/RESET position.
Connect one end of the voltmeter to the −Battery terminal.
Connect the other end of the voltmeter on wire G705 on pin X at connector P-C1 of the rigid harness.
Turn the ECS to the STOP position.
Go to the diagnostic test in the diagnostic section on CAT ET. Activate the override for the engine prelube.
Monitor the voltage on the voltmeter.
Disable the override for the engine prelube. Expected Result:The voltage is 24 3 VDC.Results:
OK - The voltage is 24 3 VDC. Proceed to Test Step 11.
Not OK - The voltage is not 24 3 VDC. Proceed to Test Step 6.Test Step 6. Check for Output Voltage from the ECM at the Connector P-C1 to the "PPR1" Relay.
Turn the ECS to the OFF/RESET position.
Connect one end of the voltmeter to the −Battery terminal.
Connect the other end of the voltmeter on wire F705 on pin c at connector P-C1 of the rigid harness.
Turn the ECS to the STOP position.
Go to the diagnostic test in the diagnostic section on CAT ET. Activate the override for the engine prelube.
Monitor the voltage on the voltmeter.
Disable the override for the engine prelube. Expected Result:The voltage is 24 3 VDC.Results:
OK - The voltage is 24 3 VDC. Proceed to Test Step 7.
Not OK - The voltage is not 24 3 VDC. Proceed to Test Step 10.Test Step 7. Check for Output Voltage to the Prelube Motor from the "PPR1" Relay.
Turn the ECS to the OFF/RESET position.
Connect one end of the voltmeter to the −Battery terminal.
Connect the other lead of the voltmeter to wire G705 on terminal 2 of the "PPR1" relay.
Turn the ECS to the STOP position.
Go to the diagnostic test in the diagnostic section on CAT ET. Activate the override for the engine prelube.
Monitor the voltage on the voltmeter.
Disable the override for the engine prelube. Expected Result:The voltage is 24 3 VDC.Results:
OK - The voltage is 24 3 VDC.Repair: Repair the wire G705 between terminal 2 of the "PPR1" relay and terminal