C6.6 Generator Set Caterpillar

The Electronic Control Module (ECM) detects the following conditions:

• The signal frequency from the digital speed control circuit is less than 150 Hz or the signal frequency is greater than 1050 Hz for more than two seconds.

• The ECM has been powered for at least three seconds.

• Diagnostic code 91-03 is not active.

• Diagnostic code 91-04 is not active.

System Response:

The ECM sets the "Throttle Position" to "0%".

If equipped, the diagnostic lamp will flash. The diagnostic code will be logged if the engine is running. The diagnostic code will not be logged if the engine is cranking.

The engine may remain at low idle while the diagnostic code is active.

This diagnostic code indicates that the frequency of a digital throttle signal is out of the normal range.

Test Step 1. Perform the following diagnostic procedure: Speed Control (PWM) - Test

Results:

• OK - STOP