COIL AS 2335927 - Caterpillar

Which Generate This Code:This diagnostic code is recorded when the power train ECM identifies a system voltage that is above 35.0 DCV. The possible causes of this diagnostic code are listed:
The voltage regulator is not operating properly.
Jump starting with a welder.System Response:The machine response is listed:
Starting is disabled.
The functions of the transmission are disabled until the voltage is above 32.0 DCV and the direction switch is placed in neutral.Note: Ensure that CID 0168 FMI 00 is active and that the diagnostic code indicator is active.Test Step 1. CHECK THE CHARGING SYSTEM.
Turn the key start switch to the ON position.
Ensure that CID 0168 FMI 00 is active. See Testing and Adjusting, "Using Caterpillar Monitoring System to Determine Diagnostic Codes".
Ensure that the diagnostic code indicator is active.Expected Result:The diagnostic code indicator is active.Results:
YES - The diagnostic code indicator is active. Proceed to test step 3.
NO - The diagnostic code indicator is not active. Proceed to test step 2.Test Step 2. CHECK THE CHARGING SYSTEM.
Start the engine.
Ensure that CID 0168 FMI 0 is active.
Observe the status of the diagnostic code indicator.Expected Result:The diagnostic code indicator is active.Results:
YES - The diagnostic code indicator is active. The charging system is charging at an excessive voltage.Repair: Check the charging system. See Troubleshooting Section, "Starting System". Stop.
NO - The diagnostic code indicator is not active. Repair: There is no problem at this time. Watch for a recurrence of this diagnostic code. Stop.Test Step 3. CHECK THE BATTERY VOLTAGE.
The engine is stopped.
At the battery, measure the voltage.Expected Result:The voltage is less than 35.0 DCV.Results:
OK - The voltage is less than 35.0 DCV. The ECM must be incorrectly recording this problem.Repair: It is unlikely that the ECM has failed. Perform the previous Steps again. If the cause of the problem is not found, replace the ECM. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace". Stop.
NOT OK - The voltage is greater than 35.0 DCV. The charging system is charging at an excessive voltage.Repair: Check the charging system. See Troubleshooting Section, "Starting System" . Stop.