Silverado Classic 2500 Power Take-Off Component Diagrams (2007)
PTO Preset Mode Function Chart
PTO - Variable Mode
The PTO speed control mode is used for both stationary and mobile applications. This mode allows PTO to be controlled in a fashion similar to cruise
control. The operator is able to hold an engine RPM between 800 and 2200 with the SET switch on the cruise stock or the PTO switch. The operator
can "tap up" to increase engine speed in 100 RPM increments with the RESUME switch. The operator may also "tap down" to decrease engine speed
with either SET switch on the cruise control multifunction switch or the PTO switch. Vehicles not equipped with cruise control will not have the "tap up"
capability.
PTO - Variable Mode Function Chart
PTO Components
PTO Switch
The PTO Switch is mounted in the center of the Instrument Panel. The PTO Switch has three positions: OFF, ON and SET. When the PTO switch is in
ON voltage will be present on the PTO On Switch Signal circuit at the relay and the PCM. When the switch is held to the SET position, voltage will be
present on the PTO Engage Signal circuit at the PCM. The PTO indicator light is integral with the switch and will illuminate when the switch is turned
ON. The presence of the indicator being on does not mean that the PTO Solenoid is engaged. The Cruise Control Multi-Function Switch may be used in
conjunction with the PTO Switch. Illumination of the switch is provided through the dimming circuit and controlled in part by internal switch logic.
Cruise Control Multi-Function Switch
The operation of the PTO system may be through the function control switches located on the multifunction turn signal lever. The cruise control function
control switches includes the ON/OFF, SET/COAST, and R/A. The switch assembly provides driver control of the PTO as well as the cruise control
system. The SET/COAST and R/A switches may be used to increase and decrease engine RPM in increments of 100 RPM. See the chart below for
recommended speeds.
PTO Relay
