Circuit Description
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
This symptom chart will aid in diagnosing a failed Power Take-Off (PTO) indicator. This diagnostic assumes that the PTO solenoid is functional and only the indicator is failing to come on. When the ignition switch is in RUN, voltage should be present on the Ignition 3 Voltage circuit. When the PTO switch is turned to ON, the LED will illuminate. The indicator has its own ground circuit. The LED and PTO solenoid have different ground circuits. Therefore, the LED may be illuminated when the PTO solenoid is disengaged.