GROMMET 3D0368 - Caterpillar

Illustration 1 g02128717
Schematic for the engine speed/timing sensors
Table 2
Troubleshooting Test Steps    Values    Results    
1. Check for Codes
A. Connect Cat ET to the service tool connector.
B. Check for Active or Logged codes.
   
190-8, 342-8 Codes
   
Result: Engine rpm is not indicated on Cat ET.
Proceed to Test Step 2.
Result: There is an active diagnostic code or a logged diagnostic code for an engine speed/timing sensor.
Proceed to Test Step 4.
   
Illustration 2 g01167684
Typical engine speed/timing sensor (1) Mounting flange (2) Mounting surface
Illustration 3 g01167704
Typical engine speed/timing sensor (3) O-ring
Table 3
Troubleshooting Test Steps    Values    Results    
2. Check the Installation of the Sensor Assembly
A. Remove electrical power from the ECM.
B. Visually inspect each sensor assembly without removing the sensor assembly from the engine. Ensure that flange (1) is installed squarely against surface (2) .
C. Remove the suspect sensor assembly from the engine.
D. Ensure that one O-ring (3) is installed on the sensor. Check the O-ring for damage. Replace the O-ring, if necessary.
   
Sensor Assembly
   
Result: The sensor's components are OK.
Repair: Perform the following procedure in order to properly install the sensor assembly:
1. Lubricate the O-ring with engine oil.
2. Fully seat the sensor assembly in the engine.
Note: If the sensor assembly will not fully seat into the engine, replace the sensor assembly.
3. Tighten the bracket bolt.
4. Connect the sensor's electrical connectors. Verify that the connectors are latched on both sides.
5. Ensure that the harness is properly secured, and that the tie-wraps are placed in the correct location.
Proceed to Test Step 3.
Result: At least one of the sensor assembly's components is not OK.
Repair: Obtain a new sensor assembly. Refer to the Disassembly and Assembly manual for installation instructions.
   
3. Inspect the Electrical Connectors and the Wiring
A. Thoroughly inspect connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect".
B. Perform a
45 N (10 lb) pull test on each of the wires that are associated with the engine speed/timing sensors.
C. Check the harness and the wiring for abrasion and for pinch points from each sensor back to the ECM.
   
Electrical Connectors and Wiring
   
Result: The harness and connectors appear to be OK.
Proceed to Test Step 4.
Result: The connectors and/or wiring are not OK.
Repair: Repair the wiring and/or the connectors. Replace parts, if necessary. 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.
If the repair does not resolve the problem, proceed to Test Step 4.
   
4. Measure the Sensor Resistance through the Engine Harness
A. Disconnect the J2/P2 ECM connectors.
B. If you are