879172021 Mercruiser HOSE

Illustration 1 g00750858
Schematic
Illustration 2 g01087228
J2/P2 ECM connector
Test Step 1. Inspect Electrical Connectors and Wiring
Turn the keyswitch to the OFF/RESET position.
Thoroughly inspect the J2/P2 ECM connector. Thoroughly inspect the connectors for each analog sensor. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connectors that are associated with the active diagnostic code.
Check the ECM connector (allen head screw) for the proper torque of 6.0 N m (55 lb in).
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 2.
Not OK - The connectors and/or wiring are not OK.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.Expected Result:No diagnostic codes are active.Results:
OK - No diagnostic codes are active.Repair: The problem may have been solved during the preceding inspection of the harness and connectors. The problem may be intermittent. If the problem is intermittent, refer to the diagnostic functional test 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 Voltage on the +5 V Supply Wire
Turn the keyswitch to the OFF/RESET position.
Disconnect all of the following analog sensors at the sensor connector:
Fuel temperature sensor J43/P43
Engine oil pressure sensor J22/P22
Atmospheric pressure sensor J27/P27
Turbocharger outlet pressure sensor J23/P23
Turbocharger inlet pressure sensor J25/P25
Coolant temperature sensor J21/P21
Air inlet temperature sensor J89/P89
Turn the keyswitch to the ON position.
Measure the voltage between terminal A (+5 V supply) and terminal B (sensor return) at the sensor connectors. Expected Result:The voltage is 5.0 0.5 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 incorrect. Proceed to Test Step 5.Test Step 4. Disconnect the +5 V Pressure Sensors while you Monitor the 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:
Fuel temperature sensor J43/P43
Engine oil pressure sensor J22/P22
Atmospheric pressure sensor J27/P27
Turbocharger outlet pressure sensor J23/P23
Turbocharger inlet pressure sensor J25/P25
Coolant temperature sensor J21/P21
Air inlet temperature sensor J89/P89Note: An 03 open circuit diagnostic code will be generated for each sensor. Troubleshoot the original code. Delete the logged diagnostic codes when you are finished.
Wait for 15 seconds after each pressure sensor is disconnected. Check for an active diagnostic code on Cat ET. Expected Result:The 262-04 diagnostic code deactivates. An 03 open circuit diagnostic code will be active for each sensor that was disconnected in the preceding steps.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 after the reconnection of the sensor, disconnect the sensor. If the problem disappears after the disconnection of the sensor, replace the sensor. Replace 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 Wire for a Short to Engine Ground or a Short to another Wire in the Harness
Turn the keyswitch to the OFF/RESET position.
Disconnect the J2/P2 ECM connector.
Leave the analog 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 ECM connector P2:36 (+5 V supply) and every terminal on ECM connector P2.
Measure the resistance between the ECM connector P2:36 and the ECM ground strap. Expected Result:The resistance is more than 20,000 Ohms.Results:
OK - The resistance is more than 20,000 Ohms. The resistance measurement does not indicate a short in the engine harness or a short to engine ground. Proceed to Test Step 6.
Not OK - The resistance is less than 20,000 Ohms. The resistance measurement indicated a short between one or more wires or between a wire and engine ground. The +5 V supply wire is shorted in the engine harness or the +5 V supply wire is shorted to engine ground.Repair: Repair the wire or replace the harness. Clear all logged diagnostic codes. Replace all wires to the original configuration. Verify that the repair eliminates the problem.STOPTest Step 6. Check the +5 V Supply and the Sensor Common for an Open Circuit
Install a wire jumper between terminal P2:36 (+5 V supply) and terminal P2:30 (sensor common). Note: Wiggle the harness during the following measurements in order to reveal any intermittent short condition.
Measure the resistance between terminal A (+5 V supply) and terminal B (sensor return) at the analog sensor connectors.
Remove the wire jumpers. Expected Result:The resistance is less than 5 Ohms.Results:
OK - The resistance is less than 5 Ohms. The resistance measurement does not indicate an open circuit in the engine harness. Proceed to Test Step 7.
Not OK - The resistance is more than 5 Ohms. The resistance measurement indicates an open circuit. The +5 V supply wire or the