CHANNEL A. 0323412 - Caterpillar

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P2 ECM connector (P2-17) Sensor return (P2-72) 5 V Sensor supply
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Sensor connector (A) 5 V or 8 V sensor supply (B) Sensor return (C) SignalTest Step 1. Inspect Electrical Connectors and Wiring
Remove electrical power from the ECM.
Thoroughly inspect the J1/P1 ECM connector and the J2/P2 ECM connector. Inspect all of the connectors that are associated with the circuit.Refer to 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 circuit.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
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 - 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.
Restore electrical power to the ECM.
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes. Look for the following diagnostic codes:
41-3
41-4
262-3
262-4
269-3
269-4 Note: Wait at least 30 seconds in order for the diagnostic codes to become active.Expected Result:No diagnostic codes are active.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 262-3, 262-4, 269-3 or 269-4 diagnostic code is active at this time. Proceed to Test Step 3.
Not OK - A 41-3 or 41-4 diagnostic code is active at this time. Proceed to Test Step 5.Test Step 3. Disconnect the 5 Volt Sensor(s) while you Monitor the Active Diagnostic Codes
Use this procedure for any 262 diagnostic codes.
Monitor the active diagnostic code screen on Cat ET while you disconnect each 5 Volt sensor at the sensor connector. Check for an active 262-3 code or an active 262-4 code.Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Disconnect the following sensors one at a time:
Fuel pressure sensor
Engine oil pressure sensor
Atmospheric pressure sensor
Intake manifold pressure sensor
Use this procedure for any 269 diagnostic codes.
Monitor the active diagnostic code screen on Cat ET while you disconnect each 5 Volt sensor at the sensor connector. Check for an active 269-3 code or an active 269-4 code.Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Disconnect the turbocharger inlet pressure sensor.
Remove electrical power from the ECM.Expected Result:The diagnostic code deactivates when a particular sensor is disconnected.Results:
OK - The diagnostic code deactivates when a particular sensor is