
All about Ford Mondeo
Ignition system - general information and precautionsEngine electrical systems / Ignition system - general information and precautions
General
The ignition system includes the ignition
switch, the battery, the crankshaft speed/
position sensor, the coil, the primary (low
tension/LT) and secondary (high tension/HT)
wiring circuits, and the spark plugs. On models
with automatic transmission, a separate
ignition module is also fitted, its functions
being incorporated in the ECU on models with
manual transmission. The ignition system is
controlled by the engine management
system’s Electronic Control Unit (ECU). Using
data provided by information sensors which
monitor various engine functions (such as
engine speed and piston position, intake air
mass and temperature, engine coolant
temperature, etc.), the ECU ensures a
perfectly-timed spark under all conditions (see
Chapter 6). Note: The ignition timing is under
the full control of the ECU, and cannot be
adjusted - see Section 8 for further details.
Precautions
When working on the ignition system, take
the following precautions:
(a) Do not keep the ignition switch on for more
than 10 seconds if the engine will not start.
(b) If a separate tachometer is ever required for servicing work, consult a dealer service department before buying a tachometer for use with this vehicle - some tachometers may be incompatible with this ignition system - and always connect it in accordance with the equipment manufacturer’s instructions.
(c) Never connect the ignition coil terminals to earth. This could result in damage to the coil and/or the ECU or ignition module (whichever is fitted).
(d) Do not disconnect the battery when the engine is running.
(e) Make sure that the ignition module (where fitted) is properly earthed.
(f) Refer to the warning at the beginning of the next Section concerning HT voltage.







