Actron 9640A manual Detonation, Duty Cycle

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Detonation:

See Knock.

DI/DIS:

Direct Ignition/Distributorless Ignition System. A system that produces the ignition spark without the use of a distributor.

DPFE:

Differential Pressure Feedback – Exhaust Gas Recirculation Sensor

DTC:

Diagnostic Trouble Code. An alphanumeric identifier for a fault condition identified by the On Board Diagnostic System.

Duty Cycle:

A term applied to signals that switch between “on” and “off”. Duty cycle is the percentage of time the signal is “on”. For example, if the signal is “on” only one fourth of the time, then the duty cycle is 25%. The PCM uses duty cycle type signals to maintain precise control of an actuator.

EBCM:

Electronic Brake Control Module

EBTCM:

Electronic Brake/Traction Control Module

ECM

Engine Control Module or Electronic Control Module

ECT:

Engine Coolant Temperature sensor. See CTS.

EEPROM:

Electrically Erasable Programmable Read Only Memory

EFE:

Early Fuel Evaporation

EFI:

Electronic Fuel Injection. Any system where a computer controls fuel delivery to the engine by using fuel injectors.

EGR:

Exhaust Gas Recirculation. The PCM uses the EGR system to recirculate exhaust gases back into the intake manifold to reduce emissions. EGR Recirculation is used only during warm engine cruise conditions. EGR flow at other times can cause stalling or no starts.

EOP:

Engine Oil Pressure (Switch)

EOT

Engine Oil Temperature (Sensor)

EPA:

Environmental Protection Agency.

ESC: B

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.

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