345C Excavator Tool Control System Caterpillar

1. Turn the disconnect switch and the key start switch to the OFF position.

2. Disconnect connector C1 from the implement ECM.

3. Disconnect the hydraulic activation relay from the machine harness.

4. Measure the resistance from connector contact C1-53 to wire (A588-GN) in the connector for the hydraulic activation relay.

Expected Result:

The resistance should be less than 5 ohms.

Results:

• OK - The resistance measurement is less than 5 ohms. Proceed to test step 2.

• NOT OK - The resistance measurement is NOT correct.

  Repair: The harness has failed. Repair the machine harness or replace the machine harness. Verify that the problem has been corrected.

  STOP

Test Step 2. CHECK FOR A SHORT TO GROUND.

1. The disconnect switch and the keyswitch remain in the OFF position.

2. The harness remains disconnected.

3. Measure the resistance from connector contact C1-53 to frame ground.

Expected Result:

The resistance should be greater than 5000 ohms.

Results:

• OK - The resistance is greater than 5000 ohms. Proceed to test step 3.

• NOT OK - The resistance measurement is less than 5000 ohms.

  Repair: The circuit is shorted to ground. Repair the circuit or replace the circuit. Verify that the problem is no longer present.

  STOP

Test Step 3. CHECK THE VOLTAGE TO THE RELAY.

1. The disconnect switch and the key start switch remain in the OFF position.

2. Reconnect connector C1.

3. Turn the disconnect switch and the key start switch to the ON position.

4. At the connector for the hydraulic activation relay, measure the voltage from wire (A588-GN) to frame ground.

Expected Result:

The voltage measurement should be 18 DCV to 24 DCV with the hydraulic lever in the ON position. The voltage measurement should be 0 DCV with the hydraulic activation lever in the OFF position.

Results:

• OK - The voltage is correct. Ensure that all connectors in the circuit are free of corrosion, properly connected, and free of debris. Reconnect all harnesses and resume normal machine operation. Watch for a recurrence.STOP

• NOT OK - The voltage is NOT correct.

  Repair: Perform the configuration of the circuit for the hydraulic activation.

  STOP