Cat® Command For Hauling Caterpillar

EID 1252 Low Machine Position Accuracy

Follow this procedure if an event EID 1252 Low Machine Position Accuracy occurs. This event code is triggered when an Autonomous Mining Truck (AMT) is not receiving an accurate position from the machine position control sensing module. Routinely as the autonomy software is running, the system performs a series of self-tests. Each time the event is triggered, the AMT will begin to make a controlled stop. Most times this event code will clear automatically and the AMT will resume normal operations. When normal operation does not resume, the problem that caused the series to terminate must be resolved. There could be other problems within the system. Once the first issue is resolved and the series is restarted, another problem could result in this event code remaining active. The troubleshooting process will need to be repeated until all self-tests pass and the event code does not reactivate.

Prior to beginning troubleshooting:

• Check and troubleshoot all diagnostic codes (CIDs).

• Check for EID 1480 GPS Receiver Antenna Separation Distance Out of Range. If this code is present, troubleshoot and clear EID 1480 prior to beginning troubleshooting for EID 1252 Low Machine Position Accuracy.

• EID 1252 may be caused by a fault that is only triggered when the AMT is in motion. Any repairs carried out as part of troubleshooting for this diagnostic should be verified. Drive the AMT in manned mode to ensure that the diagnostic is no longer active.

Test Step 1. RESTART SYSTEM

1. Key cycle the AMT.

   1. Key OFF the AMT.

   2. Wait for autonomy mode lights to turn off.

   3. Key ON AMT.

2. Wait approximately 5 minutes for the entire system to restart.

Results:

• Event code not active - STOP

• Event code still active. - Proceed to 2

Test Step 2. TRUCK LOCATION

For the AMT to confirm location, the AMT must be able to use satellite positioning or perception-based location.

1. The AMT is located in the sheltered or obstructed area. The AMT must be located in an area with clear overhead view of a large portion of sky to communicate with the satellites. Verify that clear communications with satellites can be achieved at the location of the fault. A repeated fault at the same mine site location, by the same truck, or multiple trucks could indicate an obstructed path to satellites.

2. Alternatively, the AMT is to be located in confirmed PBL location.

Move the AMT to an area with a clear overhead view of a large portion of sky. This location must not be a part of a PBL area.

Results:

• Truck location and satellite visibility improved. Event code no longer active. - STOP

• Event code still active and AMT location is acceptable. - Proceed to 3

Test Step 3. CHECK AMT IMU

The AMT IMU is mounted on the front of the truck at the top of the stairs.

1. Check that the AMT IMU mounting is not loose, misaligned, or prone to unnecessary vibrations.

2. Check that the AMT IMU is not loose and has not moved from the mounted location.

Results:

• Damage or looseness discovered in the AMT IMU mounting bracket. -

  Repair: Repair or replace the damaged mounting structure. After the repair, perform the Perception and Positioning calibrations found in Special Instruction, REHS8845, "Calibration Procedure for the 793F CMD".

  STOP

• Damage discovered for the AMT IMU. -

  Repair: Contact Caterpillar technical support with the information that has been gathered for repair instructions.

  STOP

• No visible damage or looseness discovered. - Proceed to 4

Test Step 4. ANTENNA OR COAXIAL DAMAGE

Every AMT has two GNSS antennas mounted atop two masts the front of the truck, a primary and a secondary. Both GNSS antennas are connected to the receivers in the Autonomy Cabinet via Coaxial Cables.

1. Inspect BOTH antennas for cracks or breaks on the antenna enclosures, or any other obvious signs of damage.

2. Ensure that BOTH antennas are securely mounted atop the masts on the front of the truck.

3. Inspect BOTH masts for visible cracks, obvious bends, and secureness of mounting to AMT.

4. Inspect the entire length of BOTH coaxial cables and all connectors from the antennas to the autonomy cabinet interface.

   1. Inspect cable for wear along length.

   2. Check that all connections are tight.

   3. Inspect all connectors for damage.

5. Inspect the length of BOTH coaxial cables and all connectors from the PCS to the inside of the autonomy cabinet interface.

   1. Inspect cable for wear along length.

   2. Check that all connections are tight.

   3. Inspect all connectors for damage.

Results:

• Damaged antenna discovered. -

  Repair: Replace the damaged unit.

  STOP

• One or both antennas found to be loosely mounted atop the mast. -

  Repair: Secure antenna or antennas mounting.

  STOP

• One or both masts found to be loose or damaged. -

  Repair: Repair or replace mast as necessary.

  STOP

• Coaxial damage found on one or more of the cables. -

  Repair: Reference Coaxial Best Practice Guide.

  STOP

• Loose connections are found at one or more locations. -

  Repair: Apply thread sealer. Reference Coaxial Best Practice Guide.

  STOP

• No visible damage or looseness discovered in antennas or coaxial cables. - Proceed to 5

Test Step 5. CHECK HARNESS AND CONNECTIONS

1. Check ALL the harness connections on the back of the PCS and IMU.

Results:

• Harness damage or loose connections found. -

  Repair: Repair or replace damages harness or connector.

  STOP

• No visible damage or looseness discovered. - Proceed to Test Step 6

Test Step 6. Confirm the dmi signal

1. Connect an OCS laptop to the onboard network and launch the Production OCS software.

2. Navigate to the Positioning tab.

3. When operating the truck at a safe speed, for at least 500 m (1640.4 ft), have a second person monitor the "Ground Speed Signal Data" section for loss or inconsistency of the Speed from "DMI Signal".

Expected Result:

The speed from "DMI Signal" is consistent with "Transmission Output Speed" and "Average of Rear Wheel Speeds".

Results:

• OK - The "Speed From DMI Signal" is consistent with "Transmission Output Speed" and "Average of Rear Wheel Speeds". Proceed to Test Step 7.

• NOT OK - The "Speed From DMI Signal" is not consistent with "Transmission Output Speed" and "Average of Rear Wheel Speeds".

  Repair: Complete the troubleshooting procedure for MID 039 CID 0084 FMI 02.

  1. On completion of the troubleshooting procedure for MID 039 CID 0084 FMI 02, check the status of event code E1252.

  1. If event code E1252 is active, proceed to Test Step 7.

  2. If event code E1252 is NOT active, STOP.

  STOP

Test Step 7. COLLECT DIAGNOSTIC DETAIL INFORMATION.

1. Open Cat MineStar System client.

2. Go to "Contents" > "pit link" > "Field Communications Monitor".

3. Select the comms item that displays EID 1252.

   • Collect event time from Cat ET and match to time in Cat MineStar System client.

   • In the diagnostic detail:"ComponentID"=1252.
   Show/hide table

   Illustration 1	g03392716
   Diagnostic Detail Information (A) Diagnostic Detail System

4. Once selected, the diagnostic detail message will display in the bottom left of the screen. Record the information under "extendedTexts" section.

   Note: This information will be helpful when proceeding through the process.

Expected Result:

Diagnostic details collected.

Results:

• Diagnostic details collected. Contact Caterpillar technical support with the information that has been gathered. - STOP

• Diagnostic details are not available. The cause of the problem is uncertain. Contact Caterpillar technical support with the information that has been gathered. - STOP