Cat® Command For Hauling Caterpillar

MID 039 - Machine Control Module

CID 3458 - Autonomous Steering Enable Solenoid Valve Displacement Sensor

FMI 21 - Data Drifted Low

Illustration 1	g03814403

This diagnostic code is active when the Input/Output Module (I/O Module) detects the data from the Autonomous Steering Enable Solenoid Valve Displacement Sensor ("SEL Valve Spool Pos") has drifted low, out of range.

Test Step 1. CHECK THE SENSOR.

1. Turn the keyswitch and battery disconnect to the OFF position.

2. Visually inspect the sensor and sensor wires for damage.

Expected Result:

The sensor and sensor wires are in good working condition.

Results:

• OK - The sensor and sensor wires has not been damaged. Proceed to Test Step 2.

• NOT OK - The sensor or sensor wires has been damaged.

  Repair: Replace the sensor.

  STOP

Test Step 2. CHECK POWER TO THE SENSOR.

1. Turn the keyswitch and battery disconnect to the ON position.

2. Disconnect the three-pin connector from the sensor.

3. Measure the voltage between contact A and contact B of the machine harness.

Expected Result:

The voltage measures approximately 8 V ± 2.

Results:

• OK - The measurement is approximately 8 V. Proceed to Test Step 5.

• NOT OK - The measurement is not approximately 8 V.

  Repair: There is a problem in the 8V sensor supply wire (C985-PK(Pink)) or 8V sensor return wire (C988-BK(Black)) for the sensor. Repair or replace as necessary.

  STOP

Test Step 3. EXAMINE THE SIGNAL OUTPUT FROM THE SENSOR

1. Measure the voltage on the signal output from the sensor.

Expected Result:

The voltage measure between 0.25V and 4.75V

Results:

• OK - The measurement is between 0.25V and 4.75V. Proceed to Test Step4 .

• NOT OK - The measurement is outside of 0.25V and 4.75V.

  Repair: Replace the Sensor.

  STOP

Test Step 4. COMPARE THE SIGNAL OUTPUT FROM THE SENSOR TO THE SIGNAL INPUT AT THE ECM.

1. Measure the voltage on the signal output from the sensor.

2. Measure the voltage at the signal input at the ECM.

Expected Result:

The voltage measurements are within +/- 0.2V of each other.

Results:

• OK - The measurement is within +/- 0.2V of each other. Proceed to Test Step 5.

• NOT OK - The measurement is outside of +/- 0.2V of each other.

  Repair: Repair or replace the harness.

  STOP

Test Step 5. CHECK IF THE DIAGNOSTIC CODE REMAINS.

1. Turn the keyswitch and battery disconnect to the ON position.

2. Clean the contacts of the harness connectors.

3. Reconnect all harness connectors.

4. Observe the status of the diagnostic code.

5. Cycle the keyswitch.

6. 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 now. The initial diagnostic code was probably caused by a poor electrical connection and/or a short at one of the harness connectors that was disconnected and then reconnected. Resume normal machine operation -

  STOP

• NO - The diagnostic code has not been corrected. The sensor has failed.

  Repair: Replace the sensor. After replacing the sensor, ensure that the new sensor is properly calibrated.

  STOP