Actron KAL9620A - Manual (Page 34)

34 9620 Professional OBD II Scan Tool
EPA:
Environmental Protection Agency.
ESC:
Electronic Spark Control. An ignition system function that warns the PCM when “knock”
is detected. The PCM will then retard spark timing to eliminate the knocking condition.
EST:
Electronic Spark Timing. An ignition system that allows the PCM to control spark advance
timing. The PCM determines optimum spark timing from sensor information — engine speed,
throttle position, coolant temperature, engine load, vehicle speed, Park/Neutral switch
position, and knock sensor condition.
EVAP:
Evaporative Emissions System.
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 relative
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 crankshaft or
camshaft — for spark timing and fuel injector control.
HO2S:
Heated Oxygen Sensor. See O2S.
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.
ICM:
Ignition Control Module.
I/M:
Inspection and Maintenance. An emission control program.
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 position.
ISO:
International Organization of Standardization.
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.
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.
KOEO:
Key On — Engine Off.
KOER:
Key On — Engine Running.
LCD:
Liquid Crystal Display.