CLIP 5Q4212 - Caterpillar

System Operation Description:The troubleshooting procedures for the diagnostic codes of each temperature sensor are identical. The temperature sensors are sensors that have two terminals. Terminal 2 is the common wire that is shared between all temperature sensors. The common wire provides a path to ground. Terminal 1 connects to a unique terminal on the J2/P2 ECM connector for each temperature sensor. 5 volts are supplied to the temperature sensor through terminal 1.
Illustration 1 g00994858
C-10 and C-12 sensor locations
Illustration 2 g00994860
C-15 sensor locations
Illustration 3 g00970545
Schematic for engine temperature sensors
Illustration 4 g00970546
P1 and P2 ECM connectorsTest Step 1. Inspect Electrical Connectors and Wiring
Thoroughly inspect the J2/P2 ECM connector and the suspect sensor connector. Refer to Troubleshooting, "Electrical Connections - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the sensor connector and the ECM connector that are associated with the active diagnostic code.Refer to Illustration 4.
Verify that the latch tab of the connector is properly latched and that the latch tab of the connector has returned to the Fully Latching position.
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 pinch points from the sensor to the ECM.Expected Result:All connectors, pins, and sockets should be completely coupled and/or inserted and the harness and wiring should be free of corrosion, abrasion, or pinch points.Results:
OK - Proceed to Test Step 2.
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. Determine the Condition that is Present
Connect the Caterpillar Electronic Technician (Cat ET) to the data link connector.
Turn the key switch to the ON position. Wait at least 15 seconds for activation of the diagnostic codes.
Check for active diagnostic codes on Cat ET.
Determine if the problem is related to a "voltage high" diagnostic code (open circuit) or a "voltage low" diagnostic code (short circuit).Expected Result:A "voltage high" diagnostic code (open circuit) or a "voltage low" diagnostic code (short circuit) is active.Results:
Voltage High (Open) - A "voltage high" diagnostic code (open circuit) is active at this time. Proceed to Test Step 6.
Voltage Low (Short) - A "voltage low" diagnostic code (short circuit) is active at this time. Proceed to Test Step 3.Test Step 3. Disconnect the Suspect Sensor
Turn the key switch to the OFF position.
Disconnect the sensor with the "voltage low" diagnostic code (short circuit).
Turn the key switch to the ON position. Wait at least 15 seconds for activation of the diagnostic codes.
Check for an active "voltage high" diagnostic code (open circuit) on Cat ET.Expected Result:A "voltage high" diagnostic code (open circuit) for the suspect sensor is now active.Results:
OK - A "voltage high" diagnostic code (open circuit) for the suspect sensor is now active.Repair: Temporarily connect a new sensor.If the new sensor fixes the problem, reconnect the suspect sensor.If the problem returns, permanently replace the