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• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Glossary
C
CTS:
Coolant Temperature Sensor. A resistance sensor that sends a voltage signal
to the PCM indicating the temperature of the coolant. This signal tells the PCM
whether the engine is cold or warm.
CVRTD:
Continuous Variable Real Time Damping
D/R:
Drive/Reverse
Data Link Connector (DLC):
Connector providing access and/or control of the vehicle information, operating
conditions, and diagnostic information. Vehicles with OBD II use a 16-pin
connector located in the passenger compartment.
Data Stream:
The actual data communications sent from the vehicle’s PCM to the data
connector.
DEPS:
Digital Engine Position Sensor.
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