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| Illustration 1 | g01399075 |
Schematic of the Driveline Power Take-Off (DPTO) when engaged | |
This diagnostic trouble code is associated with the driveline PTO switch. The FMI 2 recorded when the ECU reads the signal from the switch and the ECU determines that the signal is erratic, intermittent, or incorrect.
The possible causes of this diagnostic trouble code are listed:
- The DPTO switch has failed in the closed position and the driveline is engaged.
- J2-54 is shorted to ground.
- The ECU has failed.The ECU failing is unlikely.
Note: The following test procedure may create other diagnostic trouble codes. Ignore these created diagnostic trouble codes and clear the diagnostic trouble codes when the original diagnostic trouble code has been corrected. Ensure that the diagnostic trouble code of SPN 3463 FMI 2 is active before performing this procedure.
Note: Use a digital multimeter for the measurements in this procedure.
System Response:
The amber warning lamp is illuminated. The pump may not engage correctly and the machine may be allowed to move.
Test Step 1. VERIFY THE SOFTWARE VERSION
Note: Check and record the latest software version for the transmission electronic controls from SIS.
- Verify that the latest version of software has been loaded to the ECU.
Expected Result:
All of the software is current.
Results:
- OK - All of the software is current. Proceed to Test Step 2.
- NOT OK - There is a more recent software release that is available.
Repair: Flash all controls with the latest software release. Refer to Testing and Adjusting, "Electronic Control Unit - Flash Program" for more information.
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 Transmission ECM.
- Place the switch in the open or disengaged position.
- At the machine harness connector, measure the resistance from connector contact J2-54 to ground.
Expected Result:
The resistance should be more than 5000 ohms.
Results:
- OK - The resistance is more than 5000 ohms. The machine harness is correct. Proceed to test step 3.
- NOT OK - The resistance is less than 5 ohms. There is an closed circuit in the machine harness. The closed circuit exists in the wire with the low resistance.
Repair: Repair the machine harness or replace the machine harness.
STOP
Test Step 3. CHECK THE OPERATION OF THE SWITCH.
- The key start switch remains in the OFF position.
- Disconnect the switch from the machine harness.
- Place the switch in the disengaged position. Measure the resistance of the contacts with the digital multimeter. Note the resistance.
- Place the switch in the engaged position. Measure the resistance of the contacts with the digital multimeter. Note the resistance.
Expected Result:
The resistance is greater than 5000 ohms in the disengaged position and the resistance is less than 5 ohms in the engaged position.
Results:
- OK - The resistance is greater than 5000 ohms in the disengaged position and the resistance is less than 5 ohms in the engaged position. The switch is operating correctly. Proceed to Test Step 4.
- NOT OK - The resistance is less than 5 ohms in the disengaged position and in the engaged position. The switch has failed. Replace the switch. Ensure that the new switch has corrected the problem.STOP
Test Step 4. CHECK IF THE DIAGNOSTIC TROUBLE CODE IS STILL ACTIVE.
- Inspect the harness connectors. Clean the contacts of the harness connectors and check the wires for damage to the insulation that is caused by excessive heat, battery acid, or chafing.
- Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit.
- Reconnect all harness connectors in order to make sure that the connectors are fully seated. Also, make sure that the clips for each connector are completely fastened.
- Turn the disconnect switch and the key start switch to the ON position.
- Operate the machine.
- Determine if the diagnostic trouble code is active.
Expected Result:
The diagnostic trouble code is active.
Results:
- YES - The diagnostic trouble code is active. The problem has not been corrected.
Repair: Check the circuit again. It is unlikely that the ECU has failed. Exit this procedure and perform this procedure again. Prior to replacing an ECU, always contact your dealership for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the ECU requires replacement, refer to Testing and adjusting, "Electronic Control Unit - Replace".
STOP
- NO - The diagnostic trouble code is not active. The initial diagnostic trouble code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. The problem does not exist at this time. Resume normal machine operation.STOP