Actron CP9190 User Manual page 235

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Glossary
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.
Traction Assist:
Assist in traction with brakes only.
Trip:
Vehicle operation for a period of time so the systems can be monitored.
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 C
information used to determine shift points, engine load, and cruise control
functions.
VTD:
Vehicle Theft Deterrent
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