W T E C I I I E L E C T R O N I C C O N T R O L S T R O U B L E S H O O T I N G M A N U A L
DEFINITIONS AND ABBREVIATIONS
0011 00-22
2–3.
ABBREVIATIONS
A/N
Assembly Number
ABS
Anti-lock Brake System — OEM-provided means to detect and prevent wheel stoppage to
enhance vehicle handling. Retarder and engine brakes will not apply when ABS is active.
Amp
Unit of electrical current.
C3PS
C3 Pressure Switch — Pressure switch to signal the presence or absence of pressure in the
C3 clutch-apply circuit.
CAN
Controller Area Network — A network for all SAE J1939 communications in a vehicle
(engine, trnasmission, ABS, etc.)
COP
Computer Operating Properly — Hardware protection which causes the ECU to reset if
software gets lost.
CT
Closed Throttle
DDR
Diagnostic Data Reader — Diagnostic tool; most current version is the Pro-Link® 9000
made by MicroProcessor Systems, Inc. Used to interrogate the ECU for diagnostic
information and for reprogramming I/O packages in a calibration.
DNA
Does Not Adapt — Adaptive shift control is disabled.
DNS
DO NOT SHIFT — Refers to the DO NOT SHIFT diagnostic response during which the
CHECK TRANS light is illuminated and the transmission will not shift and will not
respond to the Shift Selector.
DVOM
Digital volt/ohmmeter
ECU
Electronic Control Unit (also commonly referred to as the “computer”)
GPI
General Purpose Input — Input signal to the ECU to request a special operating mode or
condition.
GPO
General Purpose Output — Output signal from the ECU to control vehicle components
(such as PTOs, backup lights, etc.) or allow a special operating mode or condition.
J1587
Engine/transmission serial data communications link.
J1939
High-speed vehicle serial data communications link.
LED
Light-Emitting Diode — Electronic device used for illumination.
NNC
Neutral No Clutches — Neutral commanded with no clutches applied.
NVL
Neutral Very Low — The ECU has sensed turbine speed below 150 rpm when output
speed is below 100 rpm and engine speed is above 400 rpm whenN (Neutral) was selected.
This is usually caused by a dragging C1 or C3 clutch or a failed turbine speed sensor. NVL
is attained by turning D solenoid “ON” (in addition to E solenoid) and the C4 and C5
clutches are applied to lock the transmission output.
OEM
Original Equipment Manufacturer — Maker of vehicle or equipment.
Ohm
Unit of electrical resistance.
OL
Over Limit or Oil Level — For Over Limit see “×”. Indicates Oil Level is being displayed
on a shift selector.
