Troubleshooting

RENR2696-01 9
Troubleshooting Section
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Glossary
Active D iagnostic Code – An active diagnostic
code alerts the
operator or the service technician that
an electronic system malfunction is currently present.
Refer to the term “Diagnostic Code” in this glossary.
Alternating Current (AC) – Alternating current is an
electric current that reverses direction at a regular
interval that
is reoccurring.
Before Top Dead Center (BTC) – BTDC is the
180 degrees o
f crankshaft rotation before the piston
reaches the top dead center position in the normal
direction of rotation.
Boost Pressure (Engines that are turbocharged) –
The difference between the turbocharger outlet
pressure an
d atmospheric pressure is commonly
referred to as boost pressure. The sensor for the
intake manifold air pressure measures the amount
of boost.
Breakout Harness – The breakout harness is a
test harnes
s that is designed to connect into the
engine harness. This connection allows a normal
circuit operation and the connection simultaneously
provides a
Breakout T in order to measure the
signals.
Bypass Cir
cuit – A bypass circuit is a circuit that is
used as a substitute circuit for an existing circuit. A
bypass circuit is typically used as a test circuit.
CAN Data Link – The CAN Data Link is a serial
communications port that is used for communication
with othe
r microprocessor based devices. In this
application, the CAN Data Link connects the ECM to
the Electronic Fuel Injection Pump.
Code – Refer to “Diagnostic Code” or “Event Code”.
Cold Mode
– Cold mode is a mode for cold starting
and for cold engine operation that includes timing
that is retarded and low idle that is raised. This
mode is u
sed for engine protection, reduced smoke
emissions and faster warm up time.
Communi
cation Adapter Tool – The
communication adapter provides a communication
link between the ECM and the Electronic Service
Tool.
Component Identifier (CID) – The CID is a number
that id
entifies the specific component of the electronic
control system that has experienced a diagnostic
code.
Coolant Level Sensor – The coolant level sensor
detects the abs
ence or presence of coolant at the
probe. The sensor then sends a signal to the ECM.
Coolant Tempe
rature Sensor – The coolant
temperature sensor detects the engine coolant
temperature for cold mode operation and for Engine
Monitoring.
Data Link – The Data Link is a serial communication
portthatisu
sed for communication with other
microprocessor based devices.
Desired Engi
ne Speed – The desired engine speed
is input to the electronic governor within the ECM.
The electronic governor uses the signal from the
throttle pos
ition sensor, the engine speed/timing
sensor, and other sensors in order to determine the
desired engine speed.
Diagnostic Code – A diagnostic code is sometimes
referred to as a fault code. These codes indicate an
electroni
c system malfunction.
Diagnostic Lamp – A diagnostic lamp is sometimes
called the
check engine light. The diagnostic lamp
is used to warn the operator of the presence of an
active diagnostic code.
Digital Sensor Return – The common line (ground)
from the ECM is used as ground for the digital
sensors.
Digital Sensors – Digital sensors produce a pulse
width modu
lated signal. Digital sensors are supplied
with +8 VDC from the ECM.
Digital S
ensor Supply – The+8VDCsupplyfrom
the ECM is used in order to power the digital sensors.
Direct Cu
rrent (DC) – Direct current is the type of
current that flows consistently in only one direction.
DT, DT Con
nector, or Deutsch DT – This is a type
of connector that is used on Perkins engines. The
connectors are manufactured by Deutsch.
Duty Cycle – Refer to “Pulse Width Modulation”.
Electron
ic Engine Control – The electronic
engine control is a complete electronic system.
The electronic engine control monitors the engine
operati
on under all conditions. The electronic engine
control also controls the engine operation under all
conditions.
Electronic Service Tool – The electronic service
tool allows a computer (PC) to communicate with the
ECM.