Equus 3123 - GM Code Reader (1982 - 1995) - Manual (Page 41)

Glossary
GM 4-2
BAC – Bypass Air Control valve.
BARO – Barometric Pressure.
BASE IDLE – Idle rpm determined by throttle switch with
idle speed control fully retracted.
BCM – Body Computer Module.
BOO – Brake On-Off input to the computer.
BOOST – Turbo charger boost solenoid or its control circuit.
BP – Barometric Pressure sensor. Used to compensate for
altitude variations.
BPMV – Brake Pressure Modulator Valve.
BTDC – Before Top Dead Center.
BVT – Back-pressure Variable Transducer.
CALPAC – A device used with fuel injection to allow fuel
delivery in the event of a PROM or PCM malfunction.
CANISTER – A container, in an evaporative emission system,
that contains charcoal to trap fuel vapors from the fuel system.
CANISTER PURGE SOLENOID – Electrical solenoid or its
control line. Solenoid opens a valve from fuel vapor canister
line to intake manifold when energized. Controls flow of
vapors between carburetor bowl vent and carbon canister.
CANP – Canister Purge solenoid.
CATALYTIC CONVERTER – Muffler like assembly placed
in exhaust system that contains a catalyst to change
hydrocarbons and carbon monoxide into water vapor and
carbon dioxide.
CCC – Climate Control Center.
CCC – Computer Command Control.
CCC – Converter Clutch Control solenoid or its circuit.
CCDIC – Climate Control/Driver Information Center.
CCO – Converter Clutch Override output from the computer
processor to the transmission.
CCS – Coast Clutch Solenoid or its circuit.
CEC – Computerized Emission Control.
CER – Cold Enrichment Rod.
CES – Clutch Engage Switch.
CFI – Central Fuel Injection.
CHECK ENGINE LIGHT – Dash panel light used either to
aid in identification and diagnosis of a system problems or to
indicate that maintenance is required.