COMPRESSOR G- 7E6807 - Caterpillar

Illustration 1 g02163817
Schematic of the Cat data link
This diagnostic code is recorded when the Advisor ECM does not receive expected information from the Chassis ECM through the Cat Data Link for more than 5 seconds.System Response:This failure results in events that are logged against an ECM that cannot be explained directly. The Advisor ECM cannot communicate with this ECM or the ECM appears to communicate intermittently.Test Step 1. VERIFY THE HARDWARE AND THE SOFTWARE PART NUMBERS.
Verify that the following information is correct:
The part number of the “Advisor ECM onboard software”
The part number of the “Chassis ECM flash software”
The part number of the Advisor ECM
The part number of the Chassis ECMNote: Consult the Business Unit that produces the product for the correct part numbers of the configuration software.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: The installed Advisor ECM or the Chassis ECM has the wrong part number or the incorrect configuration software is installed. Replace the incorrect Advisor ECM or the Chassis ECM with a module that has the correct part number. Flash the correct configuration software. See the Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program" section of this manual.STOPTest Step 2. INSPECT THE HARNESS CONNECTIONS.
Turn the disconnect switch to the OFF position.
Inspect all harness connections that are related to the Cat Data Link. Make sure that the connectors are clean and tight.
Check the connectors for proper mating. Ensure that all the seals are present and in place.
Check the harness for signs of damage or abrasion.
Check the wires at the connector. Ensure that the wires are secured tightly into the connector. Take care not to pull the wire out of the connector.
Check the exposed wires at the connectors for nicks or signs of abrasion.
Check for moisture inside the connector.
Check the connectors for dirty contacts or corroded contacts.
Check each pin and each socket of the machine harness connectors. Ensure that the contacts are properly installed. The contacts should mate correctly when the two pieces of the connector are placed together. Expected Result:The machine harness connectors are tight and free of corrosion. Results:
OK - The machine harness connectors are tight and free of corrosion. Proceed to test step 3.
NOT OK - The machine harness connectors are in need of repair.Repair: Repair the machine harness or replace the machine harness. STOPTest Step 3. CHECK FOR SHORTS TO GROUND
The disconnect switch remains in the OFF position.
Disconnect the machine harness from all electronic control modules that use the Cat Data Link.
At the machine harness for the Advisor ECM, measure the resistance between frame ground and connector contacts 8 (wire 893-GN(Green)) and connector contact 9 (wire 892-BR(Brown)) of the Cat Data Link circuit. Expected Result:The resistance is greater than 5000 ohms. Results:
OK - The resistance is greater than 5000 ohms. The harness circuit resistance is correct. Proceed to test step 4.
NOT OK - The resistance is less than 5000 ohms. The machine