en | 52 | User guide | OTC 3210 Codeconnect® with ABS & Airbag
578028 | REV. A | 05.2016
ture, engine load, vehicle speed, Park/Neutral switch
position, and knock sensor condition.
Evaporative emissions system
A block of memory containing DTCs of the vehicle oper-
ating conditions for a specific time.
Federal test procedure. Strict test of vehicle’s emissions.
An electrical conductor used as a common return for an
electric circuit(s) and with a relative zero potential
Hall effect sensor:
Any of a type of sensor utilizing a permanent magnet and
a transistorized Hall Effect switch. Hall Effect type sen-
sors may be used to measure speed and position of the
crankshaft or camshaft — for spark timing and fuel injec-
Heated oxygen sensor. See O2S.
Heating, ventilation, & air conditioning (system)
Inspection and maintenance. An emission control pro-
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.
Intake air temperature (sensor)
Ignition control module.
Intake manifold runner control
Instrument panel cluster
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
International Organization of Standardization also know
as International Standards Organization.
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 deto-
Uncontrolled ignition of the air/fuel mixture in the cylin-
der. Also referred to as detonation or ping. Knock indi-
cates extreme cylinder pressures or “hotspots” that are
causing the air/fuel mixture to detonate prematurely.
Key ON engine OFF. Turn the ignition key to on, but don’t
start the engine.
Key ON engine running. Start the vehicle.
Liquid crystal display
Long term fuel trim
Manual transmission or manual transaxle.
Mass air flow (sensor). Measures the amount and den-
sity of air entering the engine and sends a frequency or
voltage signal to the PCM. The PCM uses this signal in
its fuel delivery calculations.
Manifold absolute pressure (sensor). Measures intake
manifold vacuum or pressure and sends a frequency or
voltage signal (depending on sensor type) to the PCM.
This gives the PCM information on engine load for con-
trol of fuel delivery, spark advance, and EGR flow.
Manifold air temperature (sensor). A resistance sensor
in the intake manifold that sends a voltage signal to the
PCM indicating the temperature of the incoming air. The
PCM uses this signal for fuel delivery calculations.
Malfunction indicator lamp. The MIL is most commonly
known as the check engine or service engine soon light.
A required on-board indicator to alert the driver of an
Caused by the air fuel ratio being incorrect.
A test performed by the on-board computer to verify
proper operation of emission-related systems or compo-
MPFI or MFI:
Multi-port fuel injection. MPFI is a fuel injection system
using one (or more) injector(s) for each cylinder. The
injectors are mounted in the intake manifold, and fired in
groups rather than individually.
Oxides of nitrogen. The system EGR and Camshafts
injects exhaust gases into the intake manifold to reduce
these gases at the tailpipe.
Oxygen sensor. Generates a voltage of 0.6 to 1.1 volts
when the exhaust gas is rich (low oxygen content). The
voltage changes to 0.4 volts or less when the exhaust
gas is lean (high oxygen content). This sensor only oper-
ates after it reaches a temperature of approximately
349ºC (660ºF). O2 sensors are usually found both