 | |
| Illustration 1 | g01448176 |
Schematic of the Loader Joystick Thumbwheel Position Sensor | |
This diagnostic code is associated with the Loader Joystick Thumbwheel Position Sensor. This diagnostic code is recorded when the signal from the switch is erratic, intermittent, or incorrect.
The possible causes of this diagnostic code are listed:
- Wire (N997-WH) is shorted to the ground circuit while the machine is in operation.
- Wire (N997-WH) is shorted to the +battery.
- An open circuit exists.
- The ECM may have failed.
Note: Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, secure, and in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.
System Response:
- The system will not initialize after power is cycled.
- The hydraulic functions for extend, retract, reverse, and forward are lost after power is cycled.
- There will be no effect to the systems after powerup until the next reset of the valve ECM.
Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 2529 FMI 02 is active before performing this procedure.
Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.
Test Step 1. VERIFY SOFTWARE VERSION
Note: From SIS or the latest release of the CD for SIS, check and record the latest software version for the machine electronic controls.
- Verify the machine ECM has the latest software version loaded.
Expected Result:
All of the software is up to date.
Results:
- OK - All of the software is up to date. Proceed to Test Step 2.
- NOT OK - There is a more recent software release available.
Repair: Flash all controls with the latest software release. Refer to Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program".
STOP
Test Step 2. CHECK THE HARNESS.
- Turn the key start switch to the OFF position.
- Inspect the harness.
- Check for the proper mating.
- Check the exposed wires for nicks and abrasions.
- Check for moisture, dirt, or corrosion.
- Check the pin/socket for a proper fit.
- Disconnect the machine harness connectors from the machine ECM.
- At the machine harness connector, measure the resistance from connector contact 3 (wire N997-WH) to J2-24 (wire N997-WH) of the machine ECM.
Expected Result:
The resistance should be less than 5 ohms.
Results:
- OK - The resistance is less than 5 ohms. The machine harness is correct. Proceed to test step 3.
- NOT OK - The resistance is greater than 5 ohms. There is an open in the machine harness. The open is between the modules for the signal (wire N997-WH).
Repair: Repair the machine harness or replace the machine harness.
STOP
Test Step 3. CHECK IF THE DIAGNOSTIC CODE REMAINS.
- Clean the contacts of the harness connectors.
- Reconnect all harness connectors.
- Observe the status of the diagnostic code.
- Operate the machine.
- Observe the status of the diagnostic code.
Expected Result:
The diagnostic code is NO longer active.
Results:
- YES - The diagnostic code is NO longer active. The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor electrical connection and/or a short at one of the harness connectors. Resume normal machine operation.STOP
- NO - The diagnostic code has not been corrected. The machine ECM may have failed.
Repair: Prior to replacing an ECM, always contact your dealership Technical Communicator for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the ECM must be replaced, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
STOP