MOTOR GP-PISTON 5263938 - Caterpillar

Illustration 8 g01284098
Front view
(10) Coolant temperature sensor
(11) Turbocharger compressor outlet pressure sensor
(12) Atmospheric pressure sensor Test Step 1. Check for "Active" or "Logged" Diagnostic Codes
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Restore electrical power to the ECM.
Monitor the diagnostic codes on Cat ET. Check and record any diagnostic codes. Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Determine if a diagnostic code has occurred several times. Note: A diagnostic code that is logged several times is an indication of an intermittent problem. Most intermittent problems are the result of a bad connection between a socket and a pin in a connector or a bad connection between a wire and a terminal. The problem may be caused by moisture, corrosion, or wear.
Determine if the problem is active and related to one of the following diagnostic codes:
-3
-4Expected Result:A diagnostic code is not active.Results:
OK - A diagnostic code is not active.Repair: The problem may be intermittent. If the problem is intermittent, refer to Troubleshooting, "Inspecting Electrical Connectors".STOP
Not OK - A diagnostic code is active. Proceed to Test Step 2.Test Step 2. Check the 5 V Supply Voltage at the Sensor Connector
Do not disconnect the suspect connector.
Connect a voltmeter between pin A and pin B on the sensor side of the connector for the suspect sensor.
Measure the voltage between pin A and pin B for the suspect sensors.
Wiggle the harness while you monitor the voltage on the voltmeter. Perform the 45 N (10 lb) pull test on each wire in the circuit. Each terminal and each connector should easily withstand 45 N (10 lb) of tension and each wire should remain in the connector body. This test checks whether the wire was properly crimped in the terminal and whether the terminal was properly inserted into the connector. Expected Result:The supply voltage is 5.0 0.5 VDC.Results:
OK - The voltage is 5.0 0.5 VDC. An active -3 diagnostic code is present. Proceed to Test Step 3.
OK - The voltage is 5.0 0.5 VDC. An active -4 diagnostic code is present. Proceed to Test Step 5.
Not OK - The voltage is not 5.0 0.5 VDC. Proceed to Test Step 7.Test Step 3. Check for a Short to the +Battery at the Sensor Connector
Measure the voltage on the harness side of the sensor connector between pin B and pin C for the suspect sensors. Expected Result:The supply voltage is less than battery voltage.Results:
OK - The supply voltage is less than battery voltage. Proceed to Test Step 4.
Not OK - The supply voltage is equal to battery voltage.Repair: There is a short in the harness to the +Battery. Repair the wiring.STOPTest Step 4. Create a Short at the Sensor Connector
Remove electrical power from the ECM.
Disconnect the suspect sensor.
Use a wire jumper in order to create a short between terminal C (signal) and terminal B (sensor return) at the sensor connector.
Restore electrical power to the ECM.
Monitor the diagnostic codes on Cat ET. Check for an active -4