Actron Professional Enhanced Scan Tool 9640A, User Manual

Page: 120 / 126

Glossary
B – 4 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •
B
EVAP:
Evaporative Emissions System.
FC:
Fan Control
Freeze Frame:
A block of memory containing the vehicle operating conditions for a specific time.
Ground (GND):
An electrical conductor used as a common return for an electric circuit(s) and with a rela-
tive zero potential (voltage).
Hall Effect Sensor:
Any of a type of sensor utilizing a permanent magnet and a transistorized Hall Effect
switch. Hall Effect type sensors may be used to measure speed and position of the crank-
shaft or camshaft — for spark timing and fuel injector control.
HO2S:
Heated Oxygen Sensor. See O2S.
HVAC:
Heating, Ventilation & Air Conditioning (System)
I/M:
Inspection and Maintenance. An emission control program.
IAC:
Idle Air Control. A device mounted on the throttle body which adjusts the amount of air
bypassing a closed throttle so that the PCM can control idle speed.
IAT:
Intake Air Temperature (Sensor)
ICM:
Ignition Control Module.
IMRC:
Intake Manifold Runner Control
IPC:
Instrument Panel Cluster
ISC:
Idle Speed Control. A small electric motor mounted on the throttle body and controlled
by the PCM. The PCM can control idle speed by commanding the ISC to adjust its posi-
tion.
ISO:
International Organization of Standardization.
KAM:
Keep Alive Memory
Knock Sensor (KS):
Used to detect engine detonation or “knock.” The sensor contains a piezoelectric element
and is threaded into the engine block. Special construction makes the element sensitive
only to engine vibrations associated with detonation.
Knock:
Uncontrolled ignition of the air/fuel mixture in the cylinder. Also referred to as detonation
or ping. Knock indicates extreme cylinder pressures or “hotspots” which are causing the
air/fuel mixture to detonate prematurely.
KOEO:
Key On — Engine Off.