320C, 322C and 325C Excavators Tool Control System MID 069 - CID 1590 - FMI 03 Caterpillar

Conditions Which Generate This Code:

Illustration 1	g00803369
Schematic of the Proportional Solenoid Valve for Negative Flow Control

This diagnostic code is associated with the proportional solenoid valve for negative flow control. This diagnostic code is recorded when the implement ECM reads the voltage of the solenoid circuit as being above normal. The signal circuit of the solenoid may be shorted to the +battery circuit.

The possible causes of this diagnostic code are listed:

• The solenoid energizer circuit is shorted to the +battery circuit.

• The implement ECM has failed. This is unlikely.

System Response:

When this diagnostic code occurs, there is no warning on the monitor. The diagnostic code will be active when the control for the work tool is actuated. The diagnostic code will be active when the control for the work tool is not actuated. The diagnostic code will cause the solenoid to be energized at all times.

Test Step 1. CHECK THE SOLENOID CIRCUIT FOR A SHORT TO THE +BATTERY CIRCUIT.

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

2. Disconnect the machine harness from the solenoid.

3. Disconnect the two machine harness connectors from the implement ECM.

4. At the machine harness connector, measure the resistance from the signal contact CONN171-8 (wire M737-WH) of the machine harness to all possible sources of +battery circuit. Measure the resistance to all contacts that are used in the CONN171 and CONN172 harness connectors.

Expected Result:

Each resistance measurement should be greater than 5000 ohms.

Results:

• OK - Each resistance measurement is greater than 5000 ohms. The machine harness is correct. Proceed to test step 2.

• NOT OK - One or more resistance measurements is not correct. There is a short in the machine harness. The short is between signal contact CONN171-8 (wire M737-WH) and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harness.STOP

Test Step 2. CHECK IF THE DIAGNOSTIC CODE REMAINS.

1. Inspect the contacts of the harness connectors and clean the contacts.

2. Reconnect all harness connectors.

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

4. Enter the service mode of the operator monitor and clear all of the inactive diagnostic codes.

5. Operate the machine.

6. Determine if CID 1590 FMI 03 is present. Check the "ACTIVE ERROR" screen on the monitor.

Expected Result:

The diagnostic code for the solenoid is NOT present.

Results:

• YES - The diagnostic code is NOT present. The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation.STOP

• NO - The diagnostic code has not been corrected. It is unlikely that the implement ECM has failed.

  Repair: Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the implement ECM. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace" for the Tool Control System.

  STOP