HOUSING AS 7C6704 - Caterpillar

System Operation Description:Use this test for troubleshooting opens and/or shorts in any of the analog engine sensor circuits. These sensors provide various signals to the engine Electronic Control Module (ECM). These sensors receive a regulated supply of 5.0 VDC from the ECM.The ECM performs an automatic calibration of these sensors whenever the ECM is powered and the engine is OFF for at least five seconds. During an automatic calibration, the ECM calibrates pressure sensors against the atmospheric pressure sensor and an acceptable offset pressure range.Note: Refer to Troubleshooting, "Analog Sensor Supply Circuit - Test" if the ECM has detected a problem with the analog sensor supply voltage. Also, refer to troubleshooting, "Digital Sensor Supply Circuit - Test".
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Schematic
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P2 ECM connectorTest Step 1. Inspect Electrical Connectors and Wiring
Turn the Engine Control Switch (ECS) to the OFF/RESET position.
Thoroughly inspect the J1/P1 ECM connector, the J2/P2 ECM connector, the J3/P3 customer connector, and all other connectors in the wiring harness. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.Expected Result:All connectors, pins, and sockets are completely inserted and coupled. The harness and wiring are free of corrosion, of abrasion, and of pinch points. All connections and grounds are tight and free of corrosion.Results:
OK - Proceed to Test Step 2.
Not OK - Repair: Repair the circuit.Verify that the repair eliminates the problem. Stop.Test Step 2. Check the Sensor Supply Voltage at the Sensor Connector
Disconnect the suspect sensor.
Turn the ECS to the ON position.
Measure the voltage across terminal A (+5V Analog) and terminal B (Analog Return) at the harness