Peugeot 405. Manual - part 38

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.

Never use an ohmmeter of the type

incorporating a hand-cranked generator for
circuit or continuity testing.

Always ensure that the battery negative

lead is disconnected when working on the
electrical system.

Before using electric-arc welding

equipment on the car, disconnect the
battery, alternator and components such as
the fuel injection/ignition electronic control
unit to protect them from the risk of damage.

The radio/cassette unit fitted as standard

equipment by Peugeot is equipped with a
built-in security code to deter thieves. If the
power source to the unit is cut, the anti-theft
system will activate. Even if the power
source is immediately reconnected, the
radio/ cassette unit will not function until the
correct security code has been entered.
Therefore, if you do not know the correct
security code for the radio/cassette unit do
not disconnect the battery negative terminal
of the battery or remove the radio/cassette
unit from the vehicle. If a Peugeot
radio/cassette unit is fitted, refer to
“Radio/cassette unit anti-theft system -
precaution” in the reference section at the
rear of this manual.

2

Electrical fault-finding -
general information

Refer to Chapter 12.

3

Battery - testing and charging

1

Standard and low maintenance
battery - testing

1 If the vehicle covers a small annual mileage,
it is worthwhile checking the specific gravity
of the electrolyte every three months to
determine the state of charge of the battery.
Use a hydrometer to make the check and
compare the results with the following table.
The temperatures quoted in the table are
ambient (air) temperatures. Note that the
specific gravity readings assume an
electrolyte temperature of 15°C (60°F); for
every 10°C (50°F) below 15°C (60°F) subtract
0.007. For every 10°C (50°F) above 15°C
(60°F) add 0.007.

Above Below 
25°C(77°F)

25°C(77°F)

Fully-charged 1.210 to 1.230 1.270 to 1.290
70% charged 1.170 to 1.190 1.230 to 1.250
Discharged

1.050 to 1.070 1.110 to 1.130

2 If the battery condition is suspect, first

check the specific gravity of electrolyte in
each cell. A variation of 0.040 or more
between any cells indicates loss of electrolyte
or deterioration of the internal plates.
3 If the specific gravity variation is 0.040 or
more, the battery should be renewed. If the
cell variation is satisfactory but the battery is
discharged, it should be charged as
described later in this Section.

Maintenance-free 
battery - testing

4 In cases where a “sealed for life”
maintenance-free battery is fitted, topping-up
and testing of the electrolyte in each cell is not
possible. The condition of the battery can
therefore only be tested using a battery
condition indicator or a voltmeter.
5 Certain models may be fitted with a “Delco”
type maintenance-free battery, with a built-in
charge condition indicator. The indicator is
located in the top of the battery casing, and
indicates the condition of the battery from its
colour. If the indicator shows green, then the
battery is in a good state of charge. If the
indicator turns darker, eventually to black,
then the battery requires charging, as
described later in this Section. If the indicator
shows clear/yellow, then the electrolyte level
in the battery is too low to allow further use,
and the battery should be renewed. Do not
attempt to charge, load or jump start a battery
when the indicator shows clear/yellow.
6 If testing the battery using a voltmeter,
connect the voltmeter across the battery and
compare the result with those given in the
Specifications under “charge condition”. The
test is only accurate if the battery has not
been subjected to any kind of charge for the
previous six hours. If this is not the case,
switch on the headlights for 30 seconds, then
wait four to five minutes before testing the
battery after switching off the headlights. All
other electrical circuits must be switched off,
so check that the doors and tailgate are fully
shut when making the test.
7 If the voltage reading is less than 12.2 volts,
then the battery is discharged, whilst a
reading of 12.2 to 12.4 volts indicates a
partially discharged condition.
8 If the battery is to be charged, remove it
from the vehicle (Section 4) and charge it as
described later in this Section.

Standard and low maintenance
battery - charging

Note: The following is a guide only. Always
refer to the manufacturer’s recommendations
(often printed on a label attached to the
battery) before charging a battery.
9 Charge the battery at a rate of 3.5 to 4
amps and continue to charge the battery at
this rate unt il no further rise in specific gravity
is noted over a four hour period.
10 Alternatively, a trickle charger charging at
the rate of 1.5 amps can safely be used
overnight.
11 Specially rapid “boost” chargers which
claim to restore the battery in 1 to 2 hours are

not recommended, as they can cause damage
to the battery plates through overheating.
12 While charging the battery, note that the
temperature of the electrolyte should never
exceed 37.8°C (100°F).

Maintenance-free 
battery - charging

Note: The following is a guide only. Always
refer to the manufacturer’s recommendations
(often printed on a label attached to the
battery) before charging a battery.
13 This battery type takes considerably
longer to fully recharge than the standard
type, the time taken being dependent on the
extent of discharge, but it can take anything
up to three days.
14 A constant voltage type charger is
required, to be set, when connected, to 13.9
to 14.9 volts with a charger current below 25
amps. Using this method, the battery should
be usable within three hours, giving a voltage
reading of 12.5 volts, but this is for a partially
discharged battery and, as mentioned, full
charging can take considerably longer.
15 If the battery is to be charged from a fully
discharged state (condition reading less than
12.2 volts), have it recharged by your Peugeot
dealer or local automotive electrician, as the
charge rate is higher and constant supervision
during charging is necessary.

4

Battery - removal and refitting

1

Note: On models with a Peugeot anti-theft
alarm system, disable the alarm before
disconnecting the battery (see Chapter 12). If
a Peugeot radio/cassette unit is fitted, refer to
“Radio/cassette unit anti-theft system -
precaution”.

Removal

1 The battery is located at the right-hand rear
corner of the engine compartment.
2 Disconnect the battery terminals, negative
terminal first, by unscrewing the wing nuts or
clamp bolts. The negative terminal must
always be disconnected first, and
reconnected last (see illustration).

4.2  Battery positive terminal (A), 

negative terminal (B), clamp (C) and 

fuel damper bracket (D)

5A•2 Starting and charging systems

3 Unscrew the nuts and remove the battery
clamp.
4 Lift the battery from the battery tray. Note
the fuel damper bracket on fuel injection
models and the fuel pipes on carburettor
models.
5 If necessary, release the wiring clips and
unbolt the battery tray from the engine
compartment.

Refitting

6 Refitting is a reversal of removal, but smear
petroleum jelly on the terminals when
reconnecting the leads, and always reconnect
the positive lead first, and the negative lead
last.

5

Charging system - testing

2

Note: Refer to the warnings given in “Safety
first!” and in Section 1 of this Chapter before
starting work.
1 If the ignition warning light fails to illuminate
when the ignition is switched on, first check
the alternator wiring connections for security.
If satisfactory, check that the warning light
bulb has not blown, and that the bulbholder is
secure in its location in the instrument panel.
If the light still fails to illuminate, check the
continuity of the warning light feed wire from
the alternator to the bulbholder. If all is
satisfactory, the alternator is at fault, and
should be renewed or taken to an auto-
electrician for testing and repair.
2 If the ignition warning light illuminates when
the engine is running, stop the engine and
check that the drivebelt is correctly tensioned
(see Chapter 1) and that the alternator
connections are secure. If all is so far
satisfactory, have the alternator checked by
an auto-electrician for testing and repair.
3 If the alternator output is suspect even
though the warning light functions correctly,
the regulated voltage may be checked as
follows.
4 Connect a voltmeter across the battery
terminals, and start the engine.
5 Increase the engine speed until the
voltmeter reading remains steady; the reading

should be approximately 12 to 13 volts, and
no more than 14 volts.
6 Switch on as many electrical accessories
(eg, the headlights, heated rear window and
heater blower) as possible, and check that the
alternator maintains the regulated voltage at
around 13 to 14 volts.
7 If the regulated voltage is not as stated, the
fault may be due to worn brushes, weak brush
springs, a faulty voltage regulator, a faulty
diode, a severed phase winding, or worn or
damaged slip rings. The alternator should be
renewed or taken to an auto-electrician for
testing and repair.

6

Alternator drivebelt -
removal, refitting and
tensioning

2

Refer to the procedure given for the

auxiliary drivebelt in Chapter 1.

7

Alternator -
removal and refitting

3

Removal

1 Disconnect the battery negative lead.
2 Disconnect the electrical connections on
the rear of the alternator (see illustration).
3 Loosen the alternator mounting and
adjustment strap bolts, push the alternator
inward and slip the drivebelt off the pulley.
4 Remove the adjustment strap bolts and
alternator pivot bolts and lift off the alternator
(see illustrations).

Refitting

5 Refit in reverse order, tensioning the belt as
described in Section 6.

8

Alternator -
testing and overhaul

2

If the alternator is thought to be suspect, it

should be removed from the vehicle and taken
to an auto-electrician for testing. Most auto-

electricians will be able to supply and fit
brushes at a reasonable cost. However, check
on the cost of repairs before proceeding as it
may prove more economical to obtain a new
or exchange motor.

9

Starting system - testing

2

Note: Refer to the precautions given in
“Safety first!” and in Section 1 of this Chapter
before starting work.
1 If the starter motor fails to operate when the
ignition key is turned to the appropriate
position, the following possible causes may
be to blame.

a) The battery is faulty.
b) The electrical connections between the

switch, solenoid, battery and starter
motor are somewhere failing to pass the
necessary current from the battery
through the starter to earth.

c) The solenoid is faulty.
d) The starter motor is mechanically or

electrically defective.

2 To check the battery, switch on the
headlights. If they dim after a few seconds,
this indicates that the battery is discharged -
recharge (see Section 3) or renew the battery.
If the headlights glow brightly, operate the
ignition switch and observe the lights. If they
dim, then this indicates that current is
reaching the starter motor - therefore, the fault
must lie in the starter motor. If the lights
continue to glow brightly (and no clicking
sound can be heard from the starter motor
solenoid), this indicates that there is a fault in
the circuit or solenoid - refer to the following
paragraphs. If the starter motor turns slowly
when operated, but the battery is in good
condition, then this indicates that either the
starter motor is faulty, or there is considerable
resistance somewhere in the circuit.
3 If a fault in the circuit is suspected,
disconnect the battery leads (including the
earth connection to the body), the starter/
solenoid wiring, and the engine/transmission
earth strap. Thoroughly clean the connections,
reconnect the leads and wiring, then use a
voltmeter or test light to check that full battery

Starting and charging systems  5A•3

7.4b  . . . and lower bolt (arrowed)

7.4a  Slacken and remove the alternator

upper mounting bolt . . .

7.2  Connections on the rear of the

alternator

5A

voltage is available at the battery positive lead
connection to the solenoid, and that the earth
is sound. Smear petroleum jelly around the
battery terminals to prevent corrosion -
corroded connections are among the most
frequent causes of electrical system faults.
4 If the battery and all connections are in
good condition, check the circuit by
disconnecting the wire from the solenoid
blade terminal. Connect a voltmeter or test
light between the wire end and a good earth
(such as the battery negative terminal), and
check that the wire is live when the ignition
switch is turned to the “start” position. If it is,
then the circuit is sound - if not, the circuit
wiring can be checked as described in
Chapter 12.
5 The solenoid contacts can be checked by
connecting a voltmeter or test light between
the battery positive feed connection on the
starter side of the solenoid, and earth. When
the ignition switch is turned to the “start”
position, there should be a reading or lighted
bulb, as applicable. If there is no reading or
lighted bulb, the solenoid is faulty, and should
be renewed.
6 If the circuit and solenoid are proved
sound, the fault must lie in the starter motor.
In this event, it may be possible to have the
starter motor overhauled by a specialist, but
check on the cost of spares before
proceeding, as it may prove more economical
to obtain a new or exchange motor.

10 Starter motor -

removal and refitting

3

Removal

1 Disconnect the battery negative lead.
2 Disconnect the electrical connections to the
starter motor (see illustration).
3 Where necessary, loosen the bolts securing
the rear support bracket to the cylinder block
(see illustration).
4 Where necessary, unscrew the nuts
securing the rear of the starter motor to the
support bracket.
5 Remove the bolts securing the starter

motor to the gearbox housing (see
illustration). Note the location of any brackets
to ensure correct refitting.
6 Unclip the crankcase breather hose from
the bracket.
7 Swing the bracket rearward, then
manoeuvre the starter motor from the engine.

Refitting

8 Refitting is a reversal of the removal
procedure.

11 Starter motor -

testing and overhaul

2

If the starter motor is thought to be suspect,

it should be removed from the vehicle and
taken to an auto-electrician for testing. Most
auto-electricians will be able to supply and fit
brushes at a reasonable cost. However, check
on the cost of repairs before proceeding as it
may prove more economical to obtain a new
or exchange motor.

12 Ignition switch -

removal and refitting

2

The ignition switch is integral with the

steering column lock, and can be removed
with reference to Chapter 10.

13 Oil pressure warning light

switch - removal and refitting

2

Removal

1 The switch is located at the front of the
cylinder block, above the oil filter mounting.
Note that on some models access to the
switch may be improved if the vehicle is
jacked up and supported on axle stands so
that the switch can be reached from
underneath (see “Jacking and Vehicle
Support”).
2 Disconnect the battery negative lead.

3 Remove the protective sleeve from the
wiring plug (where applicable), then
disconnect the wiring from the switch.
4 Unscrew the switch from the cylinder block,
and recover the sealing washer. Be prepared
for oil spillage, and if the switch is to be left
removed from the engine for any length of
time, plug the hole in the cylinder block.

Refitting

5 Examine the sealing washer for signs of
damage or deterioration and if necessary
renew.
6 Refit the switch, complete with washer, and
tighten it securely. Reconnect the wiring
connector.
7 Lower the vehicle to the ground then check
and, if necessary, top-up the engine oil as
described in Chapter 1.

14 Oil level sensor -

removal and refitting

2

According to model the oil level sensor is

located on the front side of the cylinder block
just to the right of the oil filter, or on the rear
left-hand side of the cylinder block.

The removal and refitting procedure is as

described for the oil pressure switch in
Section 13. Access is most easily obtained
from underneath the vehicle (see illustration).

5A•4 Starting and charging systems

10.5  Unscrew the starter motor 

securing bolts (1). Note the location 

of the bracket (2)

14.2  Removing the oil level sensor from

the cylinder block

10.3  Starter support bracket bolts

(arrowed) on an early model

10.2  Unscrew the two nuts (arrowed) and
disconnect the wiring from the rear of the

starter motor

15 Oil temperature sensor -

removal and refitting

2

Removal

1 The oil temperature sensor is screwed into
the sump (see illustration).
2 To gain access to the sensor, firmly apply
the handbrake then jack up the front of the
vehicle and support it on axle stands (see
“Jacking and Vehicle Support”).
3 Drain the engine oil into a clean container

then refit the drain plug and tighten it to the
specified torque setting (see Chapter 1).
4 Disconnect the wiring connector then
unscrew the sensor from the sump, and
remove it from underneath the vehicle along
with its sealing washer.

Refitting

5 Examine the sealing washer for signs of
damage or deterioration and if necessary
renew.
6 Refit the sensor, tightening it securely, and
reconnect the wiring connector.
7 Lower the vehicle to the ground and refill
the engine with oil as described in Chapter 1.

Starting and charging systems  5A•5

15.1  The oil temperature sensor is

screwed into the sump

5A