GM 3123 Manuel Du Propriétaire page 44

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EMR – Electronic Module Retard, controls spark retard.
ENGINE CONTROL MODULE – A microprocessor based
device which contains electronic circuitry to control and
monitor air/fuel and emission systems, and aid in diagnostics.
EPC – Electronic Pressure Control solenoid.
EPROM – Erasable Programmable Read Only Memory.
ERS – Engine RPM Sensor.
ESA – Electronic Spark Advance.
ESC – Electronic Spark Control.
EST – Electronic Spark Timing.
EVP – EGR Valve Position sensor or its circuit.
EVR – EGR Vacuum Regulator or its circuit.
EVRV – Electronic Vacuum Regulator Valve. Controls EGR
vacuum.
EXHAUST GAS OXYGEN SENSOR – Sensor that changes
its voltage output as exhaust gas oxygen content changes as
compared to oxygen content of the atmosphere. The constantly
changing electrical signal is used to control fuel mixture.
EXHAUST GAS RECIRCULATION – Procedure where a
small amount of exhaust gas is re-admitted to combustion
chamber to reduce peak combustion temperatures, thus
reducing NOx.
FAIL SAFE – or Fail Soft: any attempt by a computer to
compensate for a fault or lost signal, usually by substituting
fixed replacement valves.
FEEDBACK CARBURETOR (FBC) – System of fuel control
employing a computer controlled solenoid that varies the
carburetors air/fuel mixture.
FMEM – Failure Mode Effects Management. Sometimes
referred to limp-in mode.
GND, GRD or GRND – Ground. Common line leading to the
negative side of the battery.
HALL EFFECT – Process where current is passed through a
small slice of semi-conductor material at the same time as a
magnetic field to produce a small voltage in the semiconductor.
HARD FAULT – Fault present during current engine
operating cycle. Opposite of an intermittent fault which does
not stay present.
HEDF – High-speed Electro-Drive Fan relay or its circuit.
HEGO – Heated Oxygen Sensor or its circuit.
HIC – Hot Idle Compensator.
4-5 GM