866170A01 Mercruiser PUMP ASSEMBLY, Fuel - Low Pressure

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Schematic for the pressure sensor supplyTest Step 1. Inspect the Electrical Connectors and the Wiring
Turn the keyswitch to the OFF position.
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C11 left side view (typical example) (1) Boost pressure sensor (2) J2/P2 ECM connector (3) Atmospheric pressure sensor (4) Engine oil pressure sensor (5) Fuel pressure sensor
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C15 left side view (typical example) (1) Boost pressure sensor (2) J2/P2 ECM connector (3) Atmospheric pressure sensor (4) Engine oil pressure sensor (5) Fuel pressure sensor
Thoroughly inspect ECM connector (2). Also, thoroughly inspect each of the connectors for sensors (1), (3), (4), and (5) .Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
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P2 ECM connector (P2-15) Boost pressure sensor (P2-17) Sensor return (P2-28) Engine oil pressure sensor (P2-40) Fuel pressure sensor (P2-57) Atmospheric pressure sensor (P2-72) +5 V Supply
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Pressure sensor connector (typical example) (A) +5 V Supply (B) Sensor return (C) Signal
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connectors that are associated with the circuit. Also perform the pull test on all pressure sensor connectors that are in the circuit.
Check the allen head screw on each of the ECM connectors for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque value.
Check the harness and wiring for abrasion and for pinch points from the sensors back to the ECM.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 harness and connectors appear to be OK. Proceed to Test Step 3.
Not OK - There is a problem with the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled. Verify that the repair eliminates the problem.STOPTest Step 2. Check for Active Diagnostic Codes
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Turn the keyswitch to the ON position.
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes.Note: Wait at least 15 seconds in order for the diagnostic codes to become active.
Determine if the problem is related to a 03 diagnostic code or a 04 diagnostic code.Expected Result:There are no active diagnostic codes.Results:
OK - No diagnostic code is active.Repair: The problem is no longer present. If the problem is intermittent, refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - A 262-03 diagnostic code is active. Proceed to Test Step 3.
Not OK - A 262-04 diagnostic code is active. Proceed to Test Step 4.Test Step 3. Check the Supply Voltage at the Sensor Connector
Turn the keyswitch to the OFF position.
Disconnect all of the following sensors at the sensor connectors:
Boost pressure sensor
Engine oil pressure sensor
Fuel pressure sensor
Atmospheric pressure sensor
Turn the keyswitch to the ON position.
Measure the voltage between terminal A (5 V sensor supply) and terminal B (sensor return) at the sensor connectors.
Turn the keyswitch to the OFF position.
Reconnect all of the sensors.Expected Result:The voltage is 5.0 0.2 VDC.Results:
OK - The voltage is correct.Repair: Replace all wires to the original configuration. Clear all diagnostic codes. Check for active diagnostic codes. If the problem is intermittent, refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - The voltage is not 5.0 0.2 VDC. The voltage is incorrect. Proceed to Test Step 5.Test Step 4. Disconnect the +5 V Sensors and Check for Active Diagnostic Codes
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes.Note: Wait at least 15 seconds in order for the diagnostic codes to become active.
Disconnect the following sensors one at a time at the sensor connector:
Boost pressure sensor
Engine oil pressure sensor
Fuel pressure sensor
Atmospheric pressure sensorExpected Result:The 262-04 diagnostic code deactivates.Results:
OK - The 262-04 diagnostic code deactivates. The diagnostic code is not active after a specific sensor is disconnected.Repair: Reconnect the sensor that is suspected of causing the problem. If the problem returns, disconnect the sensor again. If the problem does not return, replace the sensor. Reconnect all wires to the original configuration. Clear all diagnostic codes. Verify that the repair eliminates the problem.STOP
Not OK - The 262-04 diagnostic code stays active. Leave the sensors disconnected. Proceed to Test Step 5.Test Step 5. Check the +5 V Supply for a Short
Turn the keyswitch to the OFF position.
Disconnect the J2/P2 ECM connector.
Leave the pressure sensors disconnected at the sensor connectors.Note: Wiggle the harness during the following measurements in order to reveal any intermittent short condition.
Measure the resistance between P2-72 (+5 V Supply) and all of the other pins on the P2 and P1 ECM connectors.
Measure the resistance from the ECM connector P2-72 to the ECM ground strap.Expected Result:Each resistance measurement indicates an open circuit.Results: