CYLINDER PACK AS 20R0582 - Caterpillar

Illustration 1 g01966493
RS-485 network
This diagnostic code is recorded if the VIMSTM 3G Application ECM has detected an abnormal update rate from the RS-485 data link communication.System Response:This failure results in events that are logged against the VIMS 3G Application ECM that cannot be explained. The VIMS 3G Application ECM cannot communicate correctly with the RS-485 data link.Test Step 1. VERIFY THE HARDWARE AND THE SOFTWARE PART NUMBERS
Verify that the following part numbers are correct:
VIMS 3G Application ECM
VIMS 3G Application ECM softwareNote: Consult the business unit that produces the product 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. The installed VIMS 3G Application ECM has the wrong part number or the incorrect configuration software is installed.Repair: Replace the incorrect ECM with a correct ECM. See Testing and Adjusting, " Electronic Control Module (ECM) - Replace". Flash the correct configuration software. See Testing and Adjusting, " Electronic Control Module (ECM) - Flash Program".STOPTest Step 2. CHECK THE HARNESS
Turn off the key start switch.
Turn off the battery disconnect switch.
Disconnect the code-related ECMs.
Thoroughly inspect the ECM connector and the attachment connector. See Testing and Adjusting, " Electrical Connector Inspect".
Check the wiring for abrasion, kinks, and pinch points. Expected Result:The harness is good. Results:
OK - The harness is good. Proceed to Test Step 4.
NOT OK - The harness is deficient. Repair: Repair or replace the harness. STOPTest Step 3. CHECK THE 120 Ω TERMINATING RESISTORSThe disconnect switch remains off.The ECMs remain disconnected.
At the harness for the VIMS 3G Application ECM , measure the resistance between:
Contact 4 (939-WH(White)) and Contact 5 (940-BU(Blue))
Contact 17 (920-BR(Brown)) and Contact 18 (921-YL(Yellow))Expected Result:The resistance is approximately 60 Ω. Results:
OK - The resistance is approximately 60 Ω. The terminating resistors are good. Proceed to Test Step 5.
NOT OK - The resistance is not approximately 60 Ω. The machine harness or the terminating resistor has failed. Repair: Repair or replace the harness, or replace the terminating resistor. STOPTest Step 4. CHECK FOR SHORTS TO GROUNDThe disconnect switch remains off.Both VIMS 3G ECMs remain disconnected from the RS-485 data link.
At the harness for the VIMS 3G Application ECM , measure the resistance between frame ground and the following connector contacts:
Contact 4 (939-WH(White))
Contact 5 (940-BU(Blue))
Contact 6 (969-GY(Grey))
Contact 17 (920-BR(Brown))
Contact 18 (921-YL(Yellow))Expected Result:The resistance