DIODE AS-LIGHT 3E8679 - Caterpillar

Illustration 1 g03096977
Schematic of the "Power Shift" Solenoid CircuitThis diagnostic code is associated with the power shift solenoid.This is recorded when the ECM reads the voltage of the solenoid circuit as above normal (short to +battery).The possible causes of this diagnostic code are listed below:
The harness is shorted.
The ECM has failed. This is unlikely.Test Step 1. CHECK THE SIGNAL CIRCUIT FOR A SHORT.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness from the solenoid.
Disconnect the machine harness connectors J1 and J2 from the ECM.
At machine harness connector J2, measure the resistance from the solenoid signal contact J2-7 (wire L969-WH) to all other J1 and J2 connector contacts. Expected Result:Each resistance should be greater than 5000 ohms.Results:
YES - Each resistance is greater than 5000 ohms. The machine harness is correct. Proceed to test step 2.
NO - There is a short in the machine harness. Repair: The short is between the signal contact J2-7 (wire L969-WH) and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harnessSTOPTest Step 2. CHECK IF THE DIAGNOSTIC CODE REMAINS.
Inspect the contacts and clean the contacts of the harness connectors.
Reconnect all harness connectors.
Turn the disconnect switch and the key start switch to the ON position.
Clear all inactive diagnostic codes.
Operate the machine.
Stop the machine and place the parking brake switch in the ON position.
Check if the diagnostic code for the solenoid is present.Expected Result:The diagnostic code for the solenoid is NO longer present.Results:
YES - The diagnostic code is NOT present. The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operationSTOP
NO - The diagnostic code has not been corrected.Repair: It is unlikely that the ECM is faulty. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code is active. If the cause of the diagnostic code is not found, replace the ECM. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace"STOP