User Manual

Glossary • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •
B – 6 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •
B
TCM:
Transmission Control Module
TCS:
Traction Control System
TDC:
Top Dead Center. When a piston is at its
uppermost position in the cylinder.
TFP:
Transmission Fluid Pressure
TFT:
Transmission Fluid Temperature (Sensor)
Throttle Body:
A device which performs the same
function as a carburetor in a fuel injection
system. On a throttle body injection (TBI)
system, the throttle body is both the air
door and the location of the fuel injectors.
On port fuel injection systems (PFI, MPFI,
SFI, etc.), the throttle body is simply an
air door. Fuel is not added until the
injectors at each intake port are activated.
In each case, the throttle body is attached
to the accelerator pedal.
TPS:
Throttle Position Sensor.
Potentiometer-type sensor connected to
the throttle shaft. Its voltage signal output
increases as the throttle is opened. The
PCM uses this signal to control many
systems such as idle speed, spark
advance, fuel delivery, etc.
TTS:
Transmission Temperature Sensor. A
resistance sensor mounted in the
transmission housing in contact with the
transmission fluid. It sends a voltage
signal to the PCM indicating the
temperature of the transmission.
VECI:
Vehicle Emission Control Information. A
decal located in the engine compartment
containing information about the emission
control systems found on the vehicle. The
VECI is the authoritative source for
determining whether a vehicle is OBD
II-compliant.
VIN:
Vehicle Identification Number. This is the
factory-assigned vehicle serial number.
This number is stamped on a number of
locations throughout the vehicle, but the
most prominent location is on top of the
dashboard on the driver’s side, visible
from outside the car. The VIN includes
information about the car, including where
it was built, body and engine codes,
options, and a sequential build number.
VSS:
Vehicle Speed Sensor. Sends a
frequency signal to the PCM. The
frequency increases as the vehicle moves
faster to give the PCM vehicle speed
information used to determine shift points,
engine load, and cruise control functions.
VTD:
Vehicle Theft Deterrent
WOT:
Wide-Open Throttle. The vehicle operating
condition brought about when the throttle is
completely (or nearly) open. The PCM will
typically deliver extra fuel to the engine and
de-energize the A/C compressor at this time for
acceleration purposes. The PCM uses a switch
or the Throttle Position Sensor to identify the
WOT condition.