Conditions Which Generate This Code:
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| Illustration 1 | g01442621 |
Schematic for the Cat Data Link | |
This diagnostic code is recorded when the Machine ECM is unable to communicate with the Engine ECM.
The possible causes of this diagnostic code are listed as follow:
- The data link wire between the Machine ECM and the Engine ECM has failed.
System Response:
The machine response is listed:
- Machine valve calibrations will not work due to unavailable engine speed input.
- The pilot on/off solenoid valve will shut off when all the levers are in the HOLD position.
Note: Ensure that the diagnostic code is active.
Test Step 1. CHECK THE COMPATIBILITY OF THE SOFTWARE.
- For the correct software part numbers, refer to the Electronics Groups in the parts manual for the machine that is being serviced.
Expected Result:
The software is compatible.
Results:
- YES - The software is compatible. Proceed to Test Step 2.
- NO - The software is not compatible.
Repair: Flash the proper software to the appropriate ECM. Cycle the key switch in order to initialize the new software. Ensure that the diagnostic code is no longer active.
STOP
Test Step 2. CHECK THE +BATTERY CIRCUIT AT THE MACHINE ECM CONNECTORS.
- Turn the disconnect switch to the OFF position.
- Turn the key start switch to the OFF position.
- Disconnect connector J1 from the Machine ECM.
- Turn the disconnect switch and the key start switch to the ON position.
- At the connector J1, measure the voltage between all possible sources of positive voltage to all possible sources of ground.
Expected Result:
The voltage measures 18 DCV to 35 DCV.
Results:
- YES - The voltage measures 18 DCV to 35 DCV. The voltage is correct. Proceed to Test Step 3.
- NO - The voltage measures less than 18 DCV.
Repair: Ensure that there is a proper ground. Also, check the circuit breakers. If the ground is proper, the power circuit has failed. Repair the power circuit or replace the power circuit.
STOP
Test Step 3. CHECK FOR A DATA LINK CIRCUIT SHORT TO GROUND.
- Turn the disconnect switch to the OFF position.
- Turn the key start switch to the OFF position.
- Inspect the harness connectors that are related to the Cat Data Link circuits. Ensure that the connector contacts are clean and that the connectors are tight. If necessary, repair the connectors or replace the connectors.
- Disconnect the harness from all modules.
- Measure the resistance between the Cat Data Link connectors and all possible sources of ground. The Cat Data Link connectors are J1-10 and J1-20.
Expected Result:
The resistance is greater than 5000 Ohms for each measurement.
Results:
- YES - The resistance is greater than 5000 Ohms for each measurement. The machine is correct. Proceed to Test Step 4.
- NO - The resistance is less than 5000 Ohms for each measurement.
Repair: The short is between the circuit with the resistance that is less than 5000 Ohms and contact J1-10 (wire 893-GN) and contact J1-20 (wire 892-BR). Repair the harness or replace the harness.
STOP
Test Step 4. CHECK FOR A DATA LINK CIRCUIT SHORT TO POSITIVE VOLTAGE.
- The disconnect switch and the key start switch remain in the OFF position.
- All the modules remain disconnected from the harness.
- Measure the resistance between the data link and all possible sources of positive voltage at the harness connector for the ECM. The data link connectors are J1-10 and J1-20.
Expected Result:
The resistance is more than 5000 Ohms.
Results:
- YES - The resistance is more than 5000 Ohms. The harness is correct. Proceed to Test Step 5.
- NO - The resistance is less than 5000 Ohms. There is a short in the harness. The short is between the circuit with the resistance that is less than 5000 Ohms and connector contact J1-10 (wire 893-GN) or connector contact J1-20 (892-BR).
Repair: Repair the harness or replace the harness.
STOP
Test Step 5. CHECK THE DATA LINK FOR AN OPEN CIRCUIT.
- The disconnect switch remains OFF.
- All of the electronic control modules remain disconnected from the machine harness.
- At the Machine ECM, check the continuity for connector J1-10 (wire 893-GN) and connector J1-23 (wire 893-GN) for the Engine ECM .
- At the Machine ECM, check the continuity for connector J1-20 (wire 892-BR) to the corresponding connector J1-24 (wire 892-BR) for the Engine ECM.
Expected Result:
The continuity is good
Results:
- YES - The continuity is good. The circuit in the harness is correct. Proceed to Test Step 6.
- NO - The continuity is bad. The circuit is open.
Repair: Repair the harness or replace the harness.
STOP
Test Step 6. RECHECK FOR DIAGNOSTIC CODES.
- Ensure that the diagnostic code is inactive.
Expected Result:
The diagnostic code is inactive.
Results:
- YES - The diagnostic code is inactive.
Repair: The diagnostic code is no longer active.
STOP
- NO - The diagnostic code is active. The ECM may have failed.
Repair: Prior to replacing an ECM, always contact your Technical Communicator for possible consultation with AVSpare. This consultation may greatly reduce repair time. If the ECM must be replaced, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
STOP