Troubleshooting

If a functional throttle is not available, the following
conditions will occur:
• The engine will default to the limp home speed.
• If the engine speed is higher than the limp home
speed, the engine will decelerate to the limp home
speed.
• If the engine speed is lower than the limp home
speed, the engine speed will remain at the current
speed.
• The engine will remain at this speed while the
diagnostic code remains active.
• All inputs from the faulty throttle are ignored by the
ECM until the fault is repaired.
• All inputs from the repaired throttle will be ignored
by the ECM until the keyswitch has been cycled.
The diagnostic codes above relate to an analog
sensor. Use this procedure only if the analog sensor
uses an output from a variable resistor.
The sensor is most likely to be mounted on a throttle
pedal. The sensor is attached directly to the throttle
assembly. The sensor provides an output voltage to
the ECM. The sensor output voltage will vary with the
position of the throttle. Foot operated or hand
operated throttle assemblies are available.
The sensor receives +5 V power from the ECM. The
sensor will produce a raw signal voltage that will alter
between low idle and high idle.
The sensor senses the speed requirement from the
throttle position. A second sensor may override this
speed requirement from the first sensor. This
override will be subject to an input from a secondary
throttle or from the SAE J1939 (CAN) data link or
from a PTO control.
Use the electronic service tool in order to check the
input status.
UENR0612-07 219
Circuit Tests
This document has been printed from SPI2. NOT FOR RESALE