Santana PS-10, Service Manual, Page: 406 / 627

6C-24 ENGINE FUEL AND EMISSION CONTROL SYSTEM
Cold starting
If one of the three sensors (water, fuel or air) register a
temperature below 0ºC, a pre-post heating is activated.
When the ignition key is in 2nd position, the pre-heating
warning light comes on and remains on for a period which
changes according to the temperature (while the spark plug
at the entrance to the intake manifold heats the air). Later
it flashes - at this moment the engine can be started.
With the engine running, the warning light flashes and the
spark plug continues working for some time (variable),
carrying out the post-heating.
If, with the light flashing, the engine does not start within
20-25 seconds (deactivation time) the operation is cancelled
so as not to run down the batteries. The pre-heat curve
also varies according to battery voltage.
Warm starting
If the reference temperatures are above 2ºC when the key
is inserted, the warning light comes on for about 2 seconds
for a brief test and then goes out. At this moment, the
engine can be started.
Run up
When the contact is made, the control unit transfers all
the information recorded up to the last engine stoppage to
the main memory. (see After run) and carries out a system
diagnosis.
After run
Each time the engine is stopped by using the key, the
control unit remains on for a few seconds by the main
relay.
This allows the microprocessor to transfer some data from
the main memory (provisional) to the final memory. The
main memory can now be emptied and be ready to record
again (EPROM).
The data can be used for a new engine start (see run up).
This data consists mainly of
-calibration of some components
-memory of breakdowns
The procedure lasts some several seconds, normally from
2-7 (depending on the amount of data to be saved) and
then the ECU signals main relay to disconnect the battery.
CAUTION:
It is very important that this procedure is not
interrupted, eg. stopping the engine by
disconnecting from the battery, until at least 10
seconds have passed since stopping the engine.
Cut-off
This is the interruption of the fuel supply during the
deceleration of the vehicle (accelerator pedal not pressed
down).
Cylinder balancing
The individual balance of the cylinders contributes to
improved comfort.
This function consists of an individual and personalised
control of the fuel flow and the start of the injection for each
cylinder, in such a way that it can vary from cylinder to
cylinder to compensate the hydraulic tolerances of the
injector.
The differences of flow (flow characteristics) among the
injectors cannot by directly evaluated by the control board,
this information is given by reading the barcodes for each
injector during fitting by using the Modus.
Synchronisation search
If the camshaft sensor signal is not received, the control
board recognises which cylinders must have fuel injected.
If this takes place with the engine running, the succession
of combustion is established, so the control board follows
the sequence which it was already following.
If this takes place with the engine stopped, the control unit
energises only one electro-valve. Within two rotations of
the crankshaft, the injection is produced in the cylinder
and then the control unit can synchronise the order of
combustion and start the engine.