BAR A. 5B3499 - Caterpillar

Illustration 1 g06074034
Schematic for passive engine temperature sensors on the P1 connector
Not all connectors are shown. Refer to the appropriate Electrical Schematic.
Illustration 2 g03675493
Schematic for passive engine temperature sensors on the P2 connector
Illustration 3 g06255157
Schematic for passive engine temperature sensors on the DCU connector
Not all connectors are shown. Refer to the appropriate Electrical Schematic.
Illustration 4 g03714041
Typical view of a CEM temperature sensor and mating connector
(1) Signal
(2) Ground
Illustration 5 g01170313
Typical view of an engine temperature sensor
(1) Signal
(2) Ground
Table 2
Troubleshooting Test Steps Values Results
1. Check for Diagnostic Trouble Codes
A. Connect to the electronic service tool.
B. Turn the keyswitch to the ON position.
C. Access the "Active Diagnostic Code" screen on the electronic service tool.
Wait at least 30 seconds in order for the diagnostic codes to become active.
D. Look for one of the diagnostic codes that are listed in Table 1.
Codes
Result: A -3 diagnostic code is active.
Proceed to Test Step 2.
Result: A -4 or 4360-20 diagnostic code is active.
Proceed to Test Step 3.
Result: For a diagnostic code that is logged but not currently active, Proceed to Test Step 4.
2. Create a Short at the Sensor Connector
A. Turn the keyswitch to the OFF position.
B. Disconnect the suspect sensor.
C. Install the jumper wire between terminal 1 (sensor signal) and terminal 2 (sensor return) at the sensor connector.
D. Turn the keyswitch to the ON position.
E. Monitor the diagnostic codes on the electronic service tool. Check for an active -4 diagnostic code for the suspect sensor.
Wait at least 30 seconds in order for the diagnostic codes to become active.
F. Turn the keyswitch to the OFF position.
Short Circuit Recognized
Result: The -3 diagnostic code remains active for the suspect sensor.
Repair: There is an open in the harness. Repair the wiring or replace the harness.
Verify that the problem is resolved.
Result: A -4 diagnostic code became active after creating the short at the sensor connector.
Repair: The wiring is OK. Replace the sensor.
Verify that the problem is resolved.
3. Create an Open at the Suspect Sensor Connector
A. Turn the keyswitch to the OFF position.
B. Disconnect the sensor connector of the suspect sensor with the active -4 or -20 diagnostic code.
C. Turn the keyswitch to the ON position.
D. Monitor the diagnostic codes on the electronic service tool. Check for an active -3 diagnostic code for the suspect sensor.
Wait at least 30 seconds in order for the diagnostic codes to become active.
For a 110-3 code, start the engine and let the engine idle for 7 minutes. The engine must be running for at least 7 minutes in order for the diagnostic to run.
E. Turn the keyswitch to the OFF position.
Open Circuit Recognized
Result: The -4 or -20 diagnostic code remains active for the suspect sensor.
Repair: There is an open in the harness. Repair the wiring or replace the harness.
Verify that the problem is resolved.
Result: A -3 diagnostic code became active after disconnecting the sensor.
Repair: The wiring is OK. Replace the sensor.
Verify that the problem is resolved.
4. Perform the Wiggle Test
Carefully following this procedure is the best way to identify the root cause of an intermittent problem.
A. Turn the keyswitch to