Troubleshooting

RENR2696-01 11
Troubleshooting Section
Password – A password is a group of numeric
characters or a
group of alphanumeric characters
that is designed to restrict access to parameters. The
electronic system requires correct passwords in order
to change some
parameters (Facto ry Passwords).
Refer to T roubleshooting, “Factory Passwords” for
more information.
Personality M odule – This module is inside the
ECM. The module contains all the instructions
(software) f
or the ECM and the module contains
the performance maps for a specific engine. The
personality module may be reprogrammed through
flash progr
amming.
Power Cycled – Power cycled happens when power
to the ECM is
cycled: ON, OFF, and ON. Power
cycled refers to t he action of cycling the keyswitch
from any position to the OFF position, and to the
START/RUN p
osition.
Pulse Width Modulation (PWM) – The PWM is a
signal tha
t consists of pulses that are of variable
width. These pulses occur at fixed intervals. The ratio
of “TIME ON” versus total “TIME OFF” can be varied.
This ratio
is also referred to as a duty cycle.
g00284479
Illustration 3
Rated Fuel Limit – This term indicates the maximum
allowable fuel position (longest injection pulse). This
position will produce rated power for this engine
configuration.
Reference Voltage – Reference voltage is a
regulated voltage and a steady voltage that is
supplied by the ECM to a sensor. The reference
voltage is used by the sensor to generate a signal
voltage.
Sensor – A sensor is a device that is used to detect
a change in pressure, temperature, or mechanical
movement. The information that is detected is
converted into an electrical signal.
Short Circuit – A short circuit is a condition that has
an electrical c
ircuit that is inadvertently connected to
an undesirable point. An example of a short circuit
is a wire which rubs against a vehicle frame and
this rubbing e
ventually wears off the wire insulation.
Electrical contact with the frame is made and a short
circuit results.
Signal – The signal is a voltage or a waveform that
is used in order to transmit information typically from
asensortoth
eECM.
Supply Voltage – The supply voltage is a constant
voltage that
is supplied to a component in order to
provide the electrical power that is required for the
component to operate. The power may be generated
by the ECM or
the power may be battery voltage that
is supplied by the engine wiring.
System Conf
iguration Parameters – System
configuration parameters are parameters that affect
emissions and/or operating characteristics of the
engine.
Throttle P osition – Thethrottlepositionisthe
interpret
ation by the ECM of the signal from the
throttle position sensor or the throttle switch.
Throttle P
osition Sensor – The throttle position
sensor is an electronic sensor that is connected to an
accelerator pedal or a hand lever. This sensor sends
aPWMsign
al to the ECM that is used to calculate
desired engine speed.
Throttle
Switch – The throttle switch sends a signal
to the ECM that is used to calculate desired engine
speed.
TopDeadCenter –Top dead center refers to the
crankshaft position when the engine piston position
is at the
highest point of travel. The engine must be
turned in the normal direction of rotation in order to
reach this point.
Total Tattletale – The total tattletale is the total
number of changes to all the parameters that are
stored i
ntheECM.
Voltage Load Protection Module (“VLPM”) – The
“VLPM” m
onitors the voltage o f the electronic system.
The “VLPM”will eliminate any high voltage conditions
that occur. The “VLPM” will protect the fuel injection
pump fr
om any high voltage conditions that could
damage the pump.