FITTING, BARB 5MM, TURBO AIR C 5303054 - Caterpillar

Illustration 1 g00904841
Simplified Schematic of Cat Data Link (Between Machine ECM and Shifter)Note: Refer to the complete electrical system schematic of the machine being involved for complete circuit information.This diagnostic code is recorded when the machine ECM does not receive expected information from the shift lever for more than 5 seconds. Possible causes of the 668-9 diagnostic code are listed below:
An open, short, or a poor connection in the Cat data link circuit
Excessive noise on the data link circuit
The shifter controller has failed
The machine ECM has failed. This condition is unlikely.System Response:This failure results in events that are logged against an ECM that cannot be explained directly. The machine ECM cannot communicate with this ECM or the ECM appears to communicate intermittently. Test Step 1. INSPECT THE HARNESS CONNECTIONSReference Testing and Adjusting, "Electrical Connector - Inspect" in this manual
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