Perkins 1106D Troubleshooting Manual page 134

134 SENR9982
Troubleshooting Section
Digital Throttle Position Sensor
The digital throttle position sensor is used to provide
a digital throttle position signal to the Engine Control
Module (ECM). The sensor output is a constant
frequency signal with a pulse width that varies with
the pedal position. This output signal is referred to
as either a duty cycle or a pulse width modulated
signal (PWM) and this output signal is expressed as
a percentage between 3 and 100 percent.
The digital throttle position sensor is most likely to be
attached directly to the throttle pedal assembly. The
digital throttle position sensor requires no adjustment.
The digital throttle position sensor will produce a duty
cycle of 10 to 22 percent at low idle and 75 to 90
percent when the throttle pedal is fully depressed.
The percent of duty cycle is translated in the ECM
into a throttle position of 3 to 100 percent.
The digital throttle position sensor is powered by the
ECM supply voltage (+8 VDC). The supply voltage
is from the J1:43 to terminal "A" of the digital throttle
position sensor connector.
If the application is using the ECM dedicated PTO
functions, the digital throttle position sensor will be
ignored while the engine is in PTO mode.
The ECM is in PTO mode if the "PTO ON/OFF Switch"
is ON. This can be checked with Perkins Electronic
Service Tool (EST). Refer to Troubleshooting, "PTO
Switch Circuit - Test" for testing if the PTO is being
used.
g01207267
Illustration 34
Typical schematic of the digital throttle position sensor