Glossary Of Terms - Triumph Thunderbird Service Manual

Fuel System/Engine Management
Glossary of Terms
The following terms and abbreviations will be found in
this section. Below is given a brief explanation of what
some of the more common terms and abbreviations
mean.
Air temperature
The air temperature in the air box and intake hose.
Air temperature sensor
Sensor located in the airbox to detect the temperature of
the incoming air.
ATDC
After Top Dead Centre ITDC>.
Barometric pressure
Pressure of the air in the airbox.
Battery Voltage
The Voltage at the input to the Engine Control Module
(ECM).
BTDC
Before Top Dead Centre ITDC>.
Catalyst
Device placed in the exhaust system which reduces
exhaust emissions by stimulating secondary combustion
of the exhaust gases.
Closed throttle position
Throttle position at idle (Le. against end stop), measured as
a Voltage and expressed as percentage.
Coolant temperature
The coolant temperature in the cylinder head.
Coolant temperature sensor
Sensor which detects coolant temperature.
Cooling fan status
The ON or OFF condition of the cooling fan.
DTC
Diagnostic Trouble Code.
ECM
Engine Control Module.
Engine speed
The crankshaft revolutions per minute.
Freeze frame
A data set captured at the time a Diagnostic Trouble Code
(DTC> is set.
Idle fuel trim
The percentage above or below the nominal fuel
requirement for the volume of air entering at idle.
Idle fueling
Adjustment of fueling at idle to suit the actual air inducted.
Idle reference speed
The target idle speed as determined by the Electronic
Control Module (ECM). (It should be the same as the
actual idle speed if the motorcycle is operating correctly.>
Ignition advance
The timing of ignition at the spark plug relative to Top
Dead Centre.
Ignition switch position
The ON or OFF position of either or both the ignition
switch and the engine stop switch.
Ignition timing
Same as ignition advance.
Injector pulse time
The time during which an injector remains open (i.e.
delivering fuel>.
Long term fuel trim
Fueling after adapting to the engine's long term fueling
requirements (closed loop only). See also short term fuel
trim.
MAP sensor
Manifold Absolute Pressure (the air pressure in the intake
system).
MIL
Malfunction Indicator Lamp.
Illuminates when most Diagnostic Trouble Codes (DTCs)
are set.
Neutral switch status
The NEUTRAL or IN GEAR status of the transmission.
Off idle fuel trim
The percentage above or below the nominal fuel
requirement for the volume of air entering at engine
speeds other than idle. This function is not currently used
in the Triumph system.
10.14
SelVice Manual - Thunderbird