994H Large Wheel Loader VIMSTM 3G / Product Link Caterpillar

Illustration 1	g02548140
Cat® data-link circuit

This diagnostic code is recorded when the VIMS^TM Main 3G ECM receives incorrect or erratic data from the Color Multi Purpose Display (CMPD). The information is transmitted through the Cat® data-link.

System Response:

This failure results in events logged against the VIMS Main 3G ECM that cannot be explained. The VIMS Main 3G ECM cannot communicate with the CMPD or the VIMS Main 3G ECM communicates intermittently.

Test Step 1. VERIFY HARDWARE AND SOFTWARE PART NUMBERS

1. Verify that the following is correct:
   • VIMS Main 3G ECM software part number

   • VIMS Main 3G ECM part number

   • CPMD part number

   Note: Consult the product business unit for the correct part numbers.

Expected Result:

All part numbers are correct.

Results:

• OK - All part numbers are correct. Proceed to Test Step 2.

• NOT OK - All part numbers are not correct.

  Repair: Replace components that have incorrect part numbers. If an ECM was replaced, flash the correct configuration software. See, "Electronic Control Module (ECM) - Flash Program".

  STOP

Test Step 2. INSPECT THE HARNESS

1. Turn off the disconnect switch.

2. Inspect the Cat data-link portion of the harness for the following:
   • Connections are clean and tight

   • Connectors mate properly

   • Seals are in place

   • Signs of damage

   • Wires are tight in the connector

   Note: Take care not to pull the wire out of the connector.

3. Check the connectors for the following:
   • Moisture

   • Dirty contacts

   • Corroded contacts

   • Proper pin installation

   • Proper mating

Expected Result:

The harness passes inspection.

Results:

• OK - The harness passes inspection. Proceed to Test Step 3.

• NOT OK - The harness does not pass inspection.

  Repair: Repair or replace the harness.

  STOP

Test Step 3. CHECK FOR SHORTS TO GROUND

The disconnect switch remains off.

1. Disconnect all ECMs from the Cat data-link.

2. Measure the resistance between frame ground and the following VIMS 3G Main ECM connector contacts:
   • 8 (wire 893-GN)

   • 9 (wire 892-BR)

Expected Result:

The resistance is greater than 5000 ohms.

Results:

• OK - The resistance is greater than 5000 ohms. Proceed to Test Step 4.

• NOT OK - The resistance is less than 5000 ohms. There is a short between frame ground and the harness.

  Repair: Repair or replace the harness.

  STOP

Test Step 4. CHECK FOR SHORT TO +BATTERY

The disconnect switch remains off and all related ECMs remain disconnected.

1. Measure the resistance between the following CMPD connector contacts:
   • USB 7 (wire 893-GN) and Power 11 ((wire 134-YL).

   • USB 8 (wire 892-BR) and Power 11 ((wire 134-YL).

Expected Result:

The resistance is greater than 5000 ohms.

Results:

• OK - The resistance is greater than 5000 ohms. Proceed to Test Step 5.

• NOT OK - The resistance is less than 5000 ohms. There is a short between the +battery and the harness.

  Repair: Repair or replace the harness.

  STOP

Test Step 5. CHECK FOR OPEN HARNESS

The disconnect switch remains off and all related ECMs remain disconnected.

1. Measure the resistance between the following connector contacts:
   • VIMS Main 3G ECM 8 (wire 893-GN) and CMPD USB 7 (wire 893-GN).

   • VIMS Main 3G ECM 9 (wire 892-BR) and CMPD USB 8 (wire 892-BR).

Expected Result:

The resistance is less than 5 ohms.

Results:

• OK - The resistance is less than 5 ohms. Proceed to Test Step 6.

• NOT OK - The resistance is greater than 5 ohms. The harness is open.

  Repair: Repair or replace the harness.

  STOP

Test Step 6. CHECK FOR OTHER ECM DIAGNOSTIC CODES

1. Reconnect all ECMs that use Cat data-link.

2. Turn the disconnect switch and the keyswitch on.

3. Check for diagnostic codes logged against other ECMs.

Expected Result:

Other ECM diagnostic codes are not present.

Results:

• OK - Other ECM diagnostic codes are not present. The CMPD may have failed.

  Repair: Replace the CMPD module.

  STOP

• NOT OK - Other ECM diagnostic codes are present.

  Repair: Perform the troubleshooting procedure for the other diagnostic codes.

  STOP