STARTING MOTOR GP-HYDRAULIC 3843647 - Caterpillar

Illustration 1 g02729055
Schematic of the Cat Data Link
This diagnostic code is recorded when the Advisor ECM does not receive expected information. For example, engine speed or actual gear information is not received from other electronic control modules through the Cat Data Link. This diagnostic code causes the readouts, that are dependent upon the Cat Data Link information, to indicate abnormal values.The possible causes of this diagnostic code are listed in the order of probability:
A poor electrical connection at a machine harness connector
A circuit in the Cat Data Link is shorted to ground.
The Cat Data Link circuit in the machine harness is shorted to the +battery circuit.
The Cat Data Link circuit in the machine harness is open.Test Step 1. CHECK FOR OTHER CODES.
Check for similar diagnostic codes that are logged against other electronic control modules. If a similar diagnostic code is found, exit this test and perform the corresponding procedure(s) for the other diagnostic codes that are shown. Expected Result:Other diagnostic codes are showing.Results:
YES - Exit this procedure and perform the diagnostic procedure for the diagnostic codes that are shown. STOP
NO - There are no other related diagnostic codes. Proceed to test step 2. Test Step 2. INSPECT THE HARNESS CONNECTORS.
Turn the key start switch and the disconnect switch to the OFF position.
Inspect the connections of the machine harness that are related to the Cat Data Link.
Make sure that connectors are clean and tight. Expected Result:The machine harness is correct.Results:
OK - The machine harness is correct. Proceed to test step 3.
NOT OK - The machine harness is not correct. Repair: Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK FOR A SHORT TO GROUND.
The key start switch and the disconnect switch remain in the OFF position.
Disconnect the machine harness from all electronic control modules that use the Cat Data Link.
At the machine harness connector for the ECM, measure the resistance between return ground