Page 231
ee
GENERAL
The electrical system operates on 12 volts and the electri-
cal equipment comprises the following units:
Battery, starter, alternator, voltage regulator, distributor,
ignition coil with series resistance, spark plugs, outside
and inside lights, direction indicators, windshield wipers,
windshield washer, horns, heater and ventilator fan mo-
tor, radiator fan motor, brake light contact, brake warn-
ing contact, handbrake contact, temperature transmitter,
fuel level transmitter, radiator fan relay, hazard warning
flasher switch, back-up lights, wiring harness and loose
wires as well as switches and fuses.
Additional electrical equipment as from the 1970 model
comprises clock, extra light for interior illumination,
choke control contact and a contact on the gear lever
housing for manual operation of the interior lights.
As from the 1971 model, cars intended for certain mar-
kets are fitted with headlight wipers and washers. These
cars have additional relays for operation of the headlight
wipers. Illumination of switches has also been introduced
with the 1971 model.
As from the 1972 model, the cars are fitted with electric
heating of the driver's seat.
Starter
The starter is rated at 0,7 kW (1.0 hp). Its drive pinion is
moved into engagement by a control magnet operated by
the ignition key.
Ignition system
The engine has a battery ignition system consisting of an
ignition coil with serial resistance and a distributor with
a combined centrifugal and vacuum system for ignition
advance. The system is energized by the ignition key.
ELECTRICAL SYSTEM, GENERAL VIEW S 3868
On model 1974, cars intended for certain markets are
fitted with a warning system for unfastened seat belts.
Battery
The 12 volts battery is of lead-acid type with six cells. Its
capacity is 60 ampere-hours (Ah). It is located on a shelf
in the front right-hand corner of the engine compartment
with the negative pole grounded to the bodywork of the
car.
Alternator
The generator is of the AC-type. A signal light on the in-
strument panel shows whether or not the alternator is
charging.
Lights
The outside lighting consists of headlights, front parking,
direction indicators and side position lights, number plate
light, and tail lights with rear direction indicators and side
position lights, brake lights, and back-up lights which are
automatically switched on when the gear shift lever is
placed in reverse.
The headlight mountings are arranged for vertical and
lateral adjustment of the beam.
Headlights are controlled by the same lever that Operates
the direction indicators. To dim the lights, the lever is
pulled towards the steering wheel. A blue light on the
instrument panel indicates when the headlights are at
Dec. 1975 SAaB 300-1
Page 232
high beam. When the headlights are on, the parking and
tail lights are also lit.
A special rheostat on the instrument panel regulates the
intensity of the instrument panel illumination in 1970
and earlier models.
In the 1971 and 1972 models the instrument illumina-
tion is combined with the illumination of the switches
and is controlled by a switch with three positions: off,
subdued and bright.
As from model 1973, the instrument illumination is reg-
ulated with a rheostat switch, placed on the instrument
panel.
Other electrical equipment
Interior lighting consists of the dome light and ignition
switch illumination, both controlled by the dome light
switch and a contact at each door. As from the 1970
model there is an extra dome light located by the rear
view mirror and a switch on the gear lever cover for
manual operation of the interior lights. The trunk is illu-
minated by a light controlled by a contact at the hinge
of the trunk lid.
A self-canceling lever under the steering wheel controls
the current supply to the direction indicators. This lever
also controls the headlights. A green light on the instru-
ment panel indicates wnen direction indicators are oper-
ating. The warning flasher switch is located on the instru-
ment panel. All four direction indicators flash together
when this switch is actuated.
Up to and incl. model 1973, the windshield wiper motor
drives both wipers by link and wire transmission. On
model 1974, the windshield wipers are operated by a re-
ciprocating flexible cable. The switch also actuates the
windshield washer as well as the headlight wipers and
washers fitted on cars on some markets as from model 1971.
The windshield wipers have two speeds.
The horns are operated by a contact in the steering wheel
safety padding. (In the 1969 model, the horns are con-
trolled by the same lever as the windshield wipers.)
The radiator fan is driven by an electric motor and is lo-
cated behind the radiator. It is thermostat-controlled and
operates only when the coolant temperature in the radia-
tor exceeds the set cut-in temperature of the thermo-con-
tact.
As from the 1972 model, the backrest and cushion of the
drivers seat have thermostat-controlled electric heating
elements (see group 8).
300-2
Wiring and fuses
The wires leading from the battery or alternator to the
various current-consuming units are arranged in a wiring
network divided into groups. The individual wires are
color-coded for ease of identification. The terminals con-
sist of solderless AMP connectors. Fuses are provided to
protect the wiring, etc. against abnormally high current
loads (e.g. short circuits) and to reduce the risk of fire
in such an event. The fuses are grouped in a fuse box
mounted on the left wheel housing in the engine com-
partment.
The fuse box contains one spare fuse for any extra equip-
ment that may be installed.
Brake warning system
Defects in the brake system, e.g. leakage from either of
the two brake line circuits, are signaled by a brake warn-
ing light in the indicator light display instrument. The a)
light is operated by a contact located above the brake
pedal.
id
Dec. 1975
Page 233
BATTERY
General
The battery is a 12 volt lead accumulator with six cells
and a working voltage of about 2 volts per cell. The elec-
trolyte used in the battery is dilute sulphuric acid with a
spec. gravity of 1.28 at +68°F (+20°C) when the battery
is fully charged. The capacity of the battery is 60 ampere-
hours (Ah), i.e. it is rated to deliver a current of 3 amperes
for 20 hours at +68°F (+20°C). The positive pole of the
battery is connected to the starter and other current-con-
suming units and the negative pole is grounded to the
bodywork of the car.
Removing and installing the battery
To remove the battery from the car, first disconnect the
negative (ground) cable to prevent shorting, then discon-
nect the positive cable. Note that the engine must be
stopped before the terminals are disconnected, as the al-
ternator may otherwise be damaged.
Next unscrew the two wing nuts from the hooks, after
which the battery can be lifted out of the car.
Before replacing the battery, make sure that the outside
is clean and that the pole terminals and cable clamps are
also clean so that they make proper contact. After con-
necting the cables, coat the pole terminals and clamps
with acidfree vaseline.
Battery maintenance
As the ability of the battery to start the engine depends
On its state of charge, regular checking and maintenance
of the battery are important — especially in wintertime,
when the load on the starter is heavier and the capacity
of the battery is reduced by low temperature. Moreover,
an undercharged battery is apt to freeze.
Electrolyte level
The level of electrolyte in the battery tends to fall due
to evaporation and electrolytic decomposition of water.
Use only distilled water to top up. The surface of the
electrolyte should be about 0.4” (10 mm) above the top
edge of the plates.
Sulphuric acid of the correct concentration should only
be added if the spec. gravity of the electrolyte needs to
be corrected as a result of drainage or leakage from the
battery.
April 1969
Electrolyte specific gravity
The spec. gravity of the electrolyte is measured with a
hydrometer; the reading indicates the state of charge of
the battery (see table).
State of charge Spec. gravity
Full charge approx. 1.28
Half charge “4 1.21
Discharged “ 1.12
TESTING THE BATTERY
Charging
Charging must be adjusted to the capacity of the battery.
The battery is fully charged when the voltage per cell has
reached 2.5—2.7 V, without load, and has remained con-
stant during the last three hours of charging.
Decomposition of water causes the electrotype to boil.
The filler caps must therefore be removed from the cells
while charging is in progress.
CAUTION
Do not misconnect the battery. Reversing the pole
connections, even momentarily, will damage the al-
ternator rectifier. Connect the positive cable to the
positive pole of the battery (both marked +) and
the negative cable (ground lead) to the negative pole
(both marked —). If an external battery is temporar-
ily connected to the car battery, connect the poles
positive-to-positive and negative-to-negative. The
battery must not be connected to or disconnected
from the electrical system of the car while the en-
gine is urnning. When quick-charging the battery,
first disconnect the positive cable.
SAAB 311-1
Page 234
ALTERNATOR
General
While the car is running, the alternator supplies the current
needed by the various items of electrical equipment and
at the same time charges the battery.
To remove the heat generated in the alternator, its drive
pulley is provided with fan vanes that draw air through the
alternator as long as it is running.
The alternator is driven by a belt from a pulley on the crank
shaft. On engines with electronic fuel injection, the alter-
nator ts fitted with a cooling device on the 1971 and
1972 models. This consists of a hose attached to the
bottom of the radiator which conducts cool air to a
hood mounted on the rear of the alternator.
On model 1974, the alternator shaft is shortened and the
belt pulley nut is recessed into the belt pulley. This charge
applies to both Bosch and SEV alternators.
Excisting alternator types
Bosch 35 A: All carbureted engines.
Bosch 55 A: Injection engines, models 1971 and 1972.
SEV 55 A: Injection engines, as from model 1973,
and Saab 99 EMS as from model 1972.
ALTERNATOR MAKE BOSCH WITH COOLING DEVICE,
1971 AND 1972 MODELS
321-1
5s me
ALTERNATOR, MAKE SEV
Location of alternator
Up to and incl. model 1972, on the right-hand side of
the engine.
As from model 1973, on the top of the engine, 2.0 | en-
gine.
Internal wiring
The alternator is internally ventilated. It has a 12-pole
rotor and six silicon diode rectifiers. An exciter diode is
connected to each of the three stator windings, with a
common junction point at terminal D+. (Alternators for
the 1972 model 2.0 | injection engines do not have ex-
citer diodes. Instead, they are equipped with two protec-
tive diodes. See the wiring diagram.) The stator windings
comprise three phases and are star-connected. The six
rectifier diodes are arranged and wired in an AC bridge,
e.e. three diodes are wired for normal polarity (anode to
the terminal) and the other three for reverse polarity
(anode to the casing).
According to polarity, the diode holder is insulated from
the body or directly grounded by a body contact. The
annular exciter winding is mounted on the rotor, which
has pole claws, one half of the claw acting as a north pole
and the other as a south pole. The ends of the exciter
winding are connected to slip rings which transmit the
exciting current.
Dec. 1975
Page 235
Functional description
When the ignition key is turned to the drive position (K),
the circuit is energized.
The circuit runs from the ignition switch via the charge
indicator light to terminal D+ on the voltage regulator
and thence over the breaker contact to terminal DF on
the alternator, and finally through the brushes to the ex-
citer winding, after which the circuit is grounded.
The rotor is thus magnetized and a force field is generated
in the rotor.
When the engine starts and the rotor begins to spin, an al-
ternating current is generated in the stator winding; this
current is rectified as it passes the diodes and is fed into
the battery from terminal B+.
The voltage obtained from the stator winding also passes
via the exciter diodes to the voltage regulator and acts upon
the coil that controls the breaker. When the voltage rises
to 14 V or above, the magnetic field of the coil becomes
so powerful as to overcome the spring resistance of the
regulating contact and break the circuit.
To current- 4
consuming
units
Battery 12 V Ay)
Indicator ,
light ¢
The current to the exciter winding is then forced to go
through the resistance and is thus reduced, whereupon
the magnetic field strength diminishes, and with it the
strength of the alternating current generated in the sta-
tor winding. The voltage regulator thus governs the volt-
age to a maximum of about 14 V.
The charge indicator light is also influenced by the voltage
Output from the stator winding via terminal D+ on the reg-
ulator, in such a way that the voltage is equal on both sides
of the light and the light is therefore extinguished. This is
an indication that the alternator is charging.
No current-limiting relay is needed, since the alternator
itself governs the current intensity. At high alternator
speeds, when the frequency of the alternating current is
also high, and when the intensity of the output current
reaches a given value, the resulting resistance (impedance)
assumes such a magnitude that no further increase of cur-
rent is possible.
Voltage regulator AD 1 14 V
be |
|
|
c
Stator
winding
Exciter (=)
winding hs
SS
| | Alternator
| K1—= 14v 35420
Rectifiers
; Ki —— 14V 55420
|
|
|
|
|
all $ 2221
ALTERNATOR WIRING DIAGRAM, MAKE BOSCH
Sept. 1973 p
321-2
Page 236
Brushes
Exciter
winding | Exciter diode unit
Regulator
OF
Charge control light
yyvZ
Positive
rectifier
diodes
Negative
rectifier
diodes
Deviation, SEV alternator for 1972, 2.0 | engine
The alternator lacks exciter diodes. In order to prevent
a short circuit across the voltage regulator when the en-
gine is not running, the alternator is equipped with pro-
tective diodes which protect against reverse current.
Wee NAAN Dye ca oes es Be ea _To ,
VVVVV consumers
+
TY Battery \
$4059
ALTERNATOR WIRING DIAGRAM, MAKE SEV
oF B+ 0+/61
Brushes
Exciter Protecti .
. 7 if ctive;
wind' ;
ecene diodes 3
Stator
winding )
Rectifier
diodes
$ 4060
ALTERNATOR WIRING DIAGRAM, MAKE SEV, 2.0 L
ENGINES, MODEL 1972
Sept. 1973
Page 237
Maintenance B Regulator
A Alternator The regulator needs neither adjustment nor maintenance.
No lubrication is necessary. The bearings are lifetime lu-
bricated. Belt tension must be checked at regular inter-
vals. The alternator drive belt should be so taut that it
can be pressed in about 0.4” (1 cm) by a load of 3.3 Ib.
(15 N, 1.5 kp).
IMPORTANT DONT’S
— NEVER ground the exciter terminals of the al-
ternator or regulator or the connecting cable.
— NEVER reverse the regulator wiring connections.
— NEVER disconnect the regulator or the battery
while the alternator is running.
— NEVER dismantle the alternator while the bat-
tery is connected.
— NEVER start the alternator unless the cable be-
tween “’—" on the alternator and ‘’—”’ on the reg-
ulator is connected.
— NEVER test the alternator-regulator assembly in
the car or on the test bench without the battery
CHECKING BELT TENSION, UP TO AND INCL. MODEL 1972 connected.
1, Adjusting screw — NEVER reverse the battery connections, since
2. Retaining screw this will result in serious damage to the alternator.
Any necessary repairs should be done by a special-
ist electrical workshop; it is essential that disassem-
bly and testing are properly carried out, as even
small errors may result in extensive damage.
CAUTION
Before any electric welding is done on a car equipped
with an AC generator (alternator), the battery ground
cable and all wiring to the alternator must be discon-
nected, as the rectifier diodes may otherwise be dam-
aged.
CHECKING BELT TENSION, AS FROM MODEL 1973, 2.0 L
ENGINE
1. Adjusting screw
2. Retaining screw
Dec! 1976 SAAB 321-4
Page 238
Terminal clamps
Alternator
D+ Exciter diode output, terminal for regulator D+
DF Terminal to exciter winding and for regulator DF
Bt Battery connection
The indicator light is wired to D+ on the voltage regula-
tor. Connection to D— on the regulator is by a wire in
the tripole joint housing.
ALTERNATOR WIRING CONNECTIONS AND COLOR CODE,
MAKE SEV
1. 74 gray to B+ 3. 49 black to D—
2.72 red to D+ 4.73 yellow to DF
Regulator
3078
ALTERNATOR WIRING CONNECTIONS AND COLOR CODE,
MAKE BOSCH (EARLIER DESIGN)
1. 85 gray to B+ 3.72 red to D+
2. 47 black to earth (1970 and 4.73 yellow to DF
earlier models only) 5. 49 black to D—
REGULATOR, MAKE BOSCH
1.72 red to D+
2. 49 black to D—
3.73 yellow to DF
ALTERNATOR WIRING CONNECTIONS AND COLOR CODE,
MAKE BOSCH (LATER DESIGN)
1. 74 gray to B+ 3. 49 black to D—
2.72 red to D+ 4.73 yellow to DF
REGULATOR, MAKE SEV 1.72 red to D+
2. 49 black to D—
3.73 yellow to DF
321-5 SAAB Dec. 1975
Page 239
Removing and mounting the alternator
1. Disconnect the negative battery lead. Remember that
the engine must be stopped before this is done.
2. Undo the alternator wiring connections, retaining
screw and adjusting screw and take off the drive belt.
In earlier cars with 55 A Bosch alternator: Undo the
cooling hose.
3. Lift out the alternator.
4. Remount the alternator, proceeding in the reverse
order.
5. Adjust the tension of the drive belt.
The tension should be such that the belt can be de-
pressed about 0.4” (10 mm) under a load of 15 N
(3.5 Ib, 1.5 kp).
CHECKING BELT TENSION, UP TO AND INCL. MODEL 1972
1, Adjusting screw
2. Retaining screw
CHECKING BELT TENSION, AS FROM MODEL 1973, 2.0 L
ENGINE
1. Adjusting screw
2. Retaining screw
Dec. 1975
Disassembling and assembling the alternator
NOTE
To protect the diodes from overheating during solder-
ing, proceed as follows:
a. Use a well heated soldering iron with a fine tip to
do the job quickly.
b. Hold the wire between the body of the diode and
the soldering point with pliers to conduct away
as much heat as possible.
Make Bosch
Alternator, 1.7 and 1.85 | engines
S$ 2356
ALTERNATOR, 1.7 AND 1.85 L ENGINES
1. Drive bearing assembly
2. Stator
3. Slip ring end bracket
4. Rotor
SAAB 321-6
Page 240
Disassembling the alternator to exchange the bearing
1. Hold the belt pulley securely in a suitable tool and un-
screw the nut with a 7/8” (22 mm) wrench. Remove
the pulley and fan disc.
55 A alternator: Remove the cooling cover and the
cables.
2. Mark the position of the tension lug on the drive bear-
ing housing. Undo the bearing housing retaining screws
and withdraw the rotor together with the bearing hous-
ing from the stator.
3. Place the drive bearing housing on a suitable backing
surface and carefully press out the rotor. The bearing
can then be removed. Take care that the rotor does
not fall to the floor and suffer damage when it comes
free of the bearing housing.
4. Use a suitable puller to remove the ball bearing from
the slip ring side.
Assembling the alternator
The length of the brushes must be checked before the
alternator is assembled. The minimum is 0.354 in. (9 mm),
but if they are under 0.551 in. (14 mm) they should be
replaced. See section on ‘Changing brushes’’.
1. Pack the ball bearings with Bosch Ft 1 v 34 grease.
Press the ball bearing into the housing with the en-
closed side facing the drive end.
2. Press the drive bearing housing on to the rotor.
3. Press on the ball bearing on the slip ring side (see il-
lustration). The enclosed side faces the slip rings.
S$ 998
PRESSING THE SLIP RING BALL BEARING INTO POSITION
4, Put the spring washer into the bearing seat. Push up
the brushes and secure them with the brush springs
(this is easier if the brush unit assembly is removed).
BRUSHES PUSHED UP AND SECURED
5. Insert the rotor and screw the assembly together.
Make sure that the drive bearing housing is correctly
positioned relative to the slip ring bearing housing.
Press the brushes down from the outside with a screw-
driver or similar.
PRESSING DOWN THE BRUSHES
6. Fit the fan and belt pulley. The large spacer is to be
placed between the fan and the belt pulley. The small
spacer is to be placed between the belt pulley and the
spring washer. Tignten the nut to a torque of 23-29
ft.lb. (34—39 Nm, 3.5—4 kpm).
55 A alternator: Fit cables and cooling cover.
321-7 SAAB Sept. 1973