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5A
Chapter 5 Part A:
Starting and charging systems
System type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-volt, negative earth
Battery
Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Low maintenance or “maintenance-free” sealed for life
Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 to 33 Ah (depending on model)
Charge condition:
Poor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.5 volts
Normal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.6 volts
Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.7 volts
Alternator - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Alternator - testing and overhaul . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Auxiliary drivebelt check and renewal . . . . . . . . . . . . . . .See Chapter 1
Battery - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Battery - testing and charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Battery, bulbs and fuses . . . . . . . . . . . . . . . . . . . .See
“Weekly checks”
Charging system - testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electrical fault finding - general information . . . . . . . . . . . . . . . . . . . 2
Electronic oil level sensor - general information . . . . . . . . . . . . . . . . 13
General information and precautions . . . . . . . . . . . . . . . . . . . . . . . . 1
Ignition switch - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 11
Oil pressure warning light switch - removal and refitting . . . . . . . . . 12
Starter motor - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 9
Starter motor - testing and overhaul . . . . . . . . . . . . . . . . . . . . . . . . . 10
Starting system - testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5A•1
Specifications
Contents
Easy, suitable for
novice with little
experience
Fairly easy, suitable
for beginner with
some experience
Fairly difficult,
suitable for competent
DIY mechanic
Difficult, suitable for
experienced DIY
mechanic
Very difficult,
suitable for expert DIY
or professional
Degrees of difficulty
5
4
3
2
1
1 General information and
precautions
General information
The engine electrical system consists
mainly of the charging and starting systems.
Because of their engine-related functions,
these components are covered separately
from the body electrical devices such as the
lights, instruments, etc (which are covered in
Chapter 12). Information on the ignition
system is covered in Part B of this Chapter.
The electrical system is of the 12-volt
negative earth type.
The battery is of the low maintenance or
“maintenance-free” (sealed for life) type and is
charged by the alternator, which is belt-driven
from the crankshaft pulley.
The starter motor is of the pre-engaged
type incorporating an integral solenoid. On
starting, the solenoid moves the drive pinion
into engagement with the flywheel ring gear
before the starter motor is energised. Once
the engine has started, a one-way clutch
prevents the motor armature being driven by
the engine until the pinion disengages from
the flywheel.
Precautions
Further details of the various systems are
given in the relevant Sections of this Chapter.
While some repair procedures are given, the
usual course of action is to renew the
component concerned. The owner whose
interest extends beyond mere component
renewal should obtain a copy of the
“Automobile Electrical & Electronic Systems
Manual”, available from the publishers of this
manual.
It is necessary to take extra care when
working on the electrical system to avoid
damage to semi-conductor devices (diodes
and transistors), and to avoid the risk of
personal injury. In addition to the precautions
given in “Safety first!” at the beginning of this
manual, observe the following when working
on the system:
Always remove rings, watches, etc before
working on the electrical system. Even with
the battery disconnected, capacitive
discharge could occur if a component’s live
terminal is earthed through a metal object.
This could cause a shock or nasty burn.
Do not reverse the battery connections.
Components such as the alternator, electronic
control units, or any other components having
semi-conductor circuitry could be irreparably
damaged.
If the engine is being started using jump
leads and a slave battery, connect the
batteries positive-to-positive and negative-to-
negative (see “Booster battery (jump)
starting”). This also applies when connecting
a battery charger.
Never disconnect the battery terminals, the
alternator, any electrical wiring or any test
instruments when the engine is running.
Do not allow the engine to turn the
alternator when the alternator is not
connected.
Never “test” for alternator output by
“flashing” the output lead to earth.