SENSOR-TEMPERATURE 4326291 - Caterpillar

Table 2
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Determine if a code is active or logged.
Code
Result: A code is active or logged.
Proceed to Test Step 3.
Result: A code is not active or logged.
Proceed to Test Step 2.
2. Perform the "Cylinder Cutout Test"
A. Start the engine.
B. Run the engine until normal operating temperature is reached.
C. Connect Cat ET.
D. Use Cat ET to perform the following fuel injector test:
- "Cylinder Cutout Test"
E. Look for a noticeable change in fuel usage.
Fuel Usage
Result: There is a noticeable change in fuel usage. The injectors are firing on all cylinders at this time.
Proceed to Test Step 3.
Result: There is not a noticeable change in fuel usage.
Repair: Verify that the valve lash for the affected cylinder is OK. If the valve lash is OK, replace the injector.
If the problem is not resolved, proceed to Test Step 3.
3. Check the Wiring Harness between the ECM and the Injector Connectors for an Open Circuit
A. Turn the main disconnect switch to the OFF position.
Note: A strong electrical shock hazard is present if the keyswitch is not turned off.
B. Disconnect the connector for the affected cylinder at the cylinder head.
C. Fabricate a jumper wire that is long enough to create a test circuit across the harness connector at the cylinder head. Crimp connector pins to each end of the jumper wire.
D. Connect the jumper wire between the following terminal locations:
- Terminal 1 (supply) and Terminal 2 (return)
This test will effectively create a short circuit for the cylinder.
E. Connect Cat ET.
F. Use Cat ET to perform the following fuel injector test:
- "Injector Solenoid Test"
Note: Perform the test at least two times.
Wiring Harness
Result: Cat ET displays "Short" for the cylinder with the jumper wire. The wiring harness is OK.
Proceed to Test Step 4.
Result: Cat ET displays "Open" for the cylinder with the jumper wire. The ECM did not detect the jumper wire. There is an open circuit in the wiring harness.
Repair: Repair or replace the connectors or wiring. Ensure that all the seals are properly in place and ensure that the connectors