SECTION 6C1 - POWERTRAIN MANGEMENT - V6
ENGINES
CAUTION:
This vehicle will be equipped with a Supplemental Restraint System (SRS). A SRS will
consist of either seat belt pre-tensioners a driver's side air bag, or seat belt pre-
tensioners and a driver's and front passenger's side air bags. Refer to CAUTIONS,
Section 12M, before performing any service operation on or around any SRS
components, the steering mechanism or wiring. Failure to follow the CAUTIONS
could result in air bag deployment, resulting in possible personal injury or
unnecessary SRS system repairs.
CAUTION:
This vehicle may be equipped with LPG (Liquefied Petroleum Gas). In the interests of
safety, the LPG fuel system should be isolated by turning 'OFF' the manual service
valve and then draining the L PG service lines, before any service w ork is carried out
on the vehicle. Refer to the LPG leaflet included with the Owner's Handbook for
details or LPG Section 2 for more specific servicing information.
1. GENERAL DESCRIPTI ON
The V6 engines used in VT Series Models utilise an electronic module to control various functions.
Vehicles fitted with either manual or automatic transmission are equipped with a Powertrain Control Module (PCM),
which controls various engine related functions. If a vehicle is equipped with an automatic transmission, the PCM
will also control various functions within this unit.
The PCM maintains the desired air/fuel ratio at precisely 14.7 to 1 by monitoring electrical signals from dual oxy gen
sensors mounted in the exhaust stream and optimising the amount of fuel flow through the injectors.
In addition to fuel control, the PCM also controls: ignition dwell and timing, idle speed, electric fuel pump,
supercharger boost pressure (V6 Supercharged Engine), an instrument panel “CHECK ENGINE” warning lamp,
engine cooling fans and on vehicles so equipped, the air conditioning compressor clutch and /or the various
automatic transmission functions.
The PCM has a built-in diagnostic system that recognises and identifies possible operational problems and alerts
the vehicle operator by illuminating the “CHECK ENGINE” warning lamp in the instrument cluster. If the lamp
illuminates while driving, it does not mean the engine should be stopped immediately but the cause of the lamp
coming on should be investigated as soon as possible. The PCM also has an in-built back-up system that in all but
the most severe failures, allows the engine to operate at near to normal manner until repairs can be made.
For a full description of the PCM and it’s functions and controls, refer to Section 6C1, POWERTRAIN
MANAGEMENT - V6 ENGINE.