Volvo TSI, Manual

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Group 28 General
PID
Parameter Identification code.
PTO (Power Takeoff)
Operated with the cruise control switches, this mode per-
mits setting a constant engine rpm when the vehicle is
not moving.
PWM (Pulse Width Modulation)
A signal consisting of variable-width pulses at fixed inter-
vals to vary; “TIME ON” versus versus “TIME OFF.”
RAM (Random Access Memory)
A memory that has stored information immediately avail-
able when addressed.
Reference voltage
A regulated voltage supplied by the EECU to a sensor,
which uses it to generate a signal voltage.
Password
A group of seven alphanumeric characters designed to
restrict access to level-2 parameters. The password is
automatically defaulted to seven empty spaces if cus-
tomer has not specified password.
SAE
Society of Automotive Engineers.
Short circuit
A connection of comparatively low resistance, acciden-
tally or intentionally made between two points on a
circuit.
SID
Subsystem Identification code.
Signal
A voltage value used to transmit information typically
from a sensor to the EECU.
Supply voltage
A constant voltage that supplies electrical power to a
component. It may be generated by the EECU or sup-
plied by the vehicle battery.
Throttle Position Sensor (TPS)
An electronic sensor that is connected to the accelerator
pedal and sends a Pulse Width Modulated signal to the
EECU.
Vehicle Specification Programming (VSP)
VSP consists of two levels of programming: engine con-
figuration (level 1) and customer parameters (level 2).
Vehicle Speed Sensor (VSS)
An electromagnetic device that measures vehicle speed
from the rotation of gear teeth in the drivetrain of the ve-
hicle.
VEB (Volvo Engine Brake)
Consists of a compression brake (VCB) and an exhaust
pressure governor (EPG).
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