battery LAND ROVER DISCOVERY 1995 Workshop Manual

86ELECTRICAL
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DESCRIPTION AND OPERATION ALARM COMPONENT LOCATIONS (96 MODELS)
COMPONENT LOCATION
1. Electronic control unit (ECU) and relays Under dash (passenger side).................
2. Anti-theft alarm indicator light Instrument panel..................................
3. Engine immobilisation warning light (EIWL) * Instrument panel..........
4. Passive coil Over starter switch barrel.............................................................
5. Bonnet switch RH engine compartment..........................................................
6. Door switches
7. Ultrasonic sensor Interior light switch panel....................................................
8. Lock barrel, sill buttons
9. Handset and key
10. Battery backed-up sounder or horn * RH engine compartment......................
11. Immobilisation unit (spider) * Above heater...................................
12. Aerial Part of fascia harness.......................................................................
* where applicable

86ELECTRICAL
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DESCRIPTION AND OPERATION DETECTION COMPONENTS
Switches
Perimetric protection for the vehicle is provided by
ECU inputs connected to the following:
Key switches (including starter)
Sill buttons
Bonnet switch
Door switches
Ultrasonic sensor
The ultrasonic sensor is located on the interior light
switch panel and triggers the alarm if movement is
detected.
WARNING INDICATORS
Battery backed-up sounder
The battery backed-up sounder is located in the
engine compartment and provides an audible warning
whenever the alarm is triggered.
NOTE: Disconnecting the vehicle battery
will result in the alarm sounding if the
correct procedure has not been followed.
See Repair, Battery.
Engine immobilisation warning light (EIWL)
The engine immobilisation warning light is located in
the instrument pack and provides a visual indication
that the engine is immobilised.
Anti-theft alarm indicator light
The anti-theft alarm indicator light is located in the
instrument pack and provides a visual indication of the
alarm status.
Inertia switch and central door locking
As a safety feature, the alarm system is designed to
recognise the inertia switch and via the ECU, unlock
the doors in the event of a collision.
NOTE: This feature only applies when the
starter switch is in the on position.ANTI-THEFT ALARM OPERATION (96 MODELS)
Full arming and immobilisation
Locking the vehicle using the handset immobilises the
engine and initializes both volumetric and perimetric
protection, providing:
1.After a lock signal has been received, a period of
15 seconds has elapsed during which no
movement is detected inside the vehicle;
2.No door or bonnet is open.
NOTE: If either of the above conditions are
not satisfied, the alarm will only be
partially armed. This is a mislock condition
which will be made apparent by a delay of 10
seconds before the anti-theft alarm indicator
begins to flash.
Disarming the alarm
NOTE: ALWAYS disarm the alarm using
the handset.
Unlocking with the key will not disarm the alarm or
mobilise the vehicle. If the handset fails to unlock the
vehicle
See Repair, Handset.
Partial arming and immobilisation
The alarm will be partially armed and the engine
immobilised if the vehicle is locked with the handset or
key, if:
1.After a lock signal has been received, a period of
15 seconds has elapsed during which movement
is detected inside the vehicle;
2.A door or bonnet is open.
NOTE: This is a mislock condition which
will be made apparent by a delay of 10
seconds before the anti-theft alarm
indicator begins to flash. Subsequent closure of
the offending aperture will cause the alarm to
attempt full arming as previously described.
Immobilisation
The vehicle will be automatically immobilised
whenever any of the following conditions occur:
1.The vehicle is locked using the handset.
2.The vehicle is locked using the key.
3.Thirty seconds after the starter switch has been
turned off AND the driver's door opened.
4.Five minutes after the starter switch is turned off
or the alarm disarmed.

ELECTRICAL
9
DESCRIPTION AND OPERATION Mobilisation
The vehicle can be mobilised using any one of the
following processes:
1.Placing the handset in close proximity to the
starter switch with the starter switch turned on
(normally achieved by placing the key in the
starter switch, providing the key and handset are
attached).
NOTE: Under normal circumstances the
remobilisation of the vehicle will not be
apparent.
2.Pressing unlock button on handset.
3.Pressing lock button on handset with starter
switch turned on.
4.Entry of EKA code using the key.
NOTE: Any attempt to start the vehicle
using the key (detached from the handset)
will be unsuccessful. Use one of the above
methods.
See Warning indicators.
Volumetric protection
When the vehicle is locked using the handset both
perimetric and volumetric protection are activated
providing there is no mislock condition.
Perimetric protection
The vehicle is always perimetrically protected when
the alarm is armed using the handset. Perimetric
protection only, can be achieved if the vehicle is
locked using the key.
NOTE: The handset should ALWAYS be
used for unlocking the vehicle. If the
handset fails to unlock the vehicle
See
Repair, Handset.
Battery backed-up sounder (BBUS)
The sounder provides audible indication of alarm
status including:
Anti-theft warnings;
Confirmation of access to built-in test.
NOTE: Disconnecting the vehicle battery
will result in the alarm sounding if the
correct procedure has not been followed.
See Repair, Battery.
Alarm horn
The horn provides audible indication (as BBUS) of
alarm status.
NOTE: Disconnecting the vehicle battery
will have no effect on the horn.
Engine immobilisation warning light (EIWL)
NOTE: Under normal circumstances the
light will not illuminate.
The light will only illuminate (after 2 seconds) if the
handset is detached from the key (or the handset
fails) and an attempt is made to start the vehicle.
Anti-theft alarm indicator light
The light flashes to indicate the alarm status.
If the alarm system is fully armed, the light will flash
rapidly for 10 seconds and then settle to the slow
(anti-theft deterrent) flash.
If the alarm system is perimetrically armed, the light
will intermittently flash rapidly for 10 seconds and then
settle to the slow (anti-theft deterrent) flash.
If the alarm system is partially armed, the light will
NOT emit the slow flash until 10 seconds after arming
(to allow the cause to be investigated).
If the vehicle has been left unlocked, providing the
driver's door is closed, the light will flash slowly
indicating immobilisation. If the driver's door is open,
the light will remain illuminated.
Emergency key access (EKA)
The emergency key access code should be entered in
accordance with the instructions in the Owner's
Handbook.

ELECTRICAL
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FAULT DIAGNOSIS GENERAL INFORMATION
The electrical fault diagnostic tool on Discovery
vehicles is Testbook. Detailed information of electrical
systems, component locations and circuit diagrams
are covered in the Discovery Electrical
Troubleshooting Manual.
See INTRODUCTION,
Information, Fault Diagnostic Equipment
This section covers checks of the charging and
ignition system.
GENERATOR TESTING
Service repair no - 86.10.01
Charging system check
1.Check battery is in good condition, with an open
circuit voltage of at least 12.6 V. Recharge or
substitute battery to carry out test.
2.Check drive belt condition.
See SECTION 10,
Maintenance, Under Bonnet [Hood]
Maintenance
3.Check battery connections are clean and tight.
4.Check generator connections are clean and
tight.
5.Ensure there is no drain on battery from, for
example, interior, under bonnet [hood] or door
edge lamps.
Generator test
Following instructions refer to use of suitable test
equipment using a carbon pile rheostat.
6.Connect test equipment referring to
manufacturer's instructions.
7.Start engine and run at 3000 rev/min without
accessory load.
8.Rotate carbon pile load control to achieve
greatest output (amps) without allowing voltage
to fall below 12.0 V. A reading in amps, of
generator output, minus 10% to allow for EFI
and Ignition loss, should be obtained.
9.Run engine at 3000 rev/min, switch selector to
regulator test, read voltmeter. A reading of 13.6
to 14.4 V should be obtained.
10.Switch selector to diode/stator test, switch on
headlamps to load generator. Raise engine
speed to 3000 rev/min, read voltmeter, needle
must be within 'OK' range.TESTING IN POSITION
Charging circuit resistance test.
1.Connect a low range voltmeter between
generator terminal marked B+ and positive
terminal of battery.2.Switch on headlamps, start engine. Run engine
at approximately 3000 rev/min. Note voltmeter
reading.
3.Transfer voltmeter connections to frame of
generator and negative terminal of battery, and
again note voltmeter reading.
4.If reading exceeds 0.5 volt on positive side or
0.25 volt on negative side, there is a high
resistance in charging circuit which must be
traced and remedied.

86ELECTRICAL
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FAULT DIAGNOSIS LUCAS CONSTANT ENERGY IGNITION SYSTEM -
V8i
Preliminary checks
Inspect battery cables and connections to ensure they
are clean and tight. Check electrical condition of
battery.
Inspect all L.T. connections, ensure they are clean
and tight. Check H.T. leads are correctly positioned
and not shorting to ground against any engine
components. Wiring harness and individual cables
should be firmly fastened to prevent chaffing.
Pick-up air gap
Check air gap between pick-up limb and reluctor teeth
is 0.20 - 0.35 mm, using a non-ferrous gauge.
NOTE: Air gap is set initially at factory and
will only require adjusting if tampered with
or when pick-up module is replaced.
TEST 1:
H.T. Sparking
Remove coil/distributor H.T. lead from distributor
cover and hold approximately 6mm from engine block,
using suitable insulated pliers. Switch ignition 'On' and
operate starter.
Regular sparking indicates fault in H.T. distribution,
plugs, timing or fuelling, proceed to Test 6. If no spark
or weak spark occurs proceed to Test 2.TEST 2:
L.T. Voltage
Switch ignition 'On' - engine stationary.
(a) Connect voltmeter to points in circuit indicated
by V1 to V4 and make a note of voltage
readings.
(b) Compare voltages obtained with specified
values listed below:
Expected readings
V1 More than 12 volts.
V2 1 volt maximum below volts at V1.
V3 1 volt maximum below volts at V1.
V4 0 volt - 0.1 volt.
(c) If all readings are correct proceed to Test 3.
(d) Check incorrect reading(s) with chart to identify
area of possible faults, i.e. faults listed under
heading SUSPECT and rectify.
(e) If coil and amplifier is suspected, disconnect L.T.
lead at coil, repeat V3. If voltage is still incorrect,
fit new coil. If voltage is now correct, check L.T.
lead, if satisfactory fit new amplifier.
(f) If engine will not start proceed to Test 3.

ELECTRICAL
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FAULT DIAGNOSIS 1 2 3 4 SUSPECT
L * * * DISCHARGED BATTERY
* L L * IGN. SWITCH AND/OR
WIRING
* * L * COIL OR AMPLIFIER
* * * H AMPLIFIER GROUND
Key
*Expected Voltage
HVoltage higher than expected
LVoltage lower than expectedTEST 3:
Amplifier Switching
Connect voltmeter between battery positive (+ve)
terminal and H.T. coil negative (-ve) terminal.
Voltmeter should register 0 volts.
Switch ignition 'On', voltmeter should still register 0
volts.
Crank engine, voltmeter reading should increase
when cranking, in which case proceed to Test 5.
If no increase in voltage during cranking proceed to
Test 4.

ELECTRICAL
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REPAIR BATTERY
Service repair no - 86.15.01
NOTE: Some vehicles are fitted with a
battery backed-up sounder. Disconnecting
the vehicle battery will cause the alarm to
sound unless the following procedure is followed:
1.Turn starter switch 'ON' then 'OFF'.
2.Disconnect battery WITHIN 15 SECONDS (see
WARNING).
If alarm is accidentally activated, ensure sounder is
connected and silence by turning the starter switch to
position II.
Remove
WARNING: During battery removal or
before carrying out any repairs or
maintenance to electrical components
always disconnect battery negative lead first. If
positive lead is disconnected with negative lead in
place, accidental contact of wrench to any
grounded metal part could cause a severe spark,
possibly resulting in personal injury. Upon
installation of battery connect positive lead first.
3.Disconnect both battery leads, negative first.
4.Release four nuts securing battery bracket in
position.
5.Remove bracket.
6.Remove battery.
Refit
7.Reverse removal procedure.
NOTE: Coat battery clamps and terminals
with petroleum jelly before refitting.DISTRIBUTOR-LUCAS 35 DLM8 - V8i
Service parts
1. Cap
2. HT brush and spring
3. Rotor arm
4. Insulation cover
5. Pick-up module and base plate assembly
6. Vacuum unit
7. Amplifier module
8. 'O'-ring oil seal
9. Gasket

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REPAIR ELECTRONIC IGNITION - V8i
A Lucas 35DLM8 distributor is employed. This has a
conventional vacuum advance unit and centrifugal
automatic advance mechanism.
A pick-up module, in conjunction with a rotating timing
reluctor inside distributor body, generates timing
signals. These are applied to an electronic ignition
amplifier module mounted on side of distributor body.
NOTE: Pick-up air gap is factory set. Do
not adjust gap unless pick-up is being
changed or base plate has been moved.
Use a non-ferrous feeler gauge to set air gap.
IGNITION COIL
Service repair no - 86.35.32
Remove
1.Disconnect battery negative lead.
2.Noting their fitted positions, disconnect electrical
leads from ignition coil.
3.Remove two bolts securing ignition coil clamp,
recover suppressor.
4.Remove coil.
Refit
5.Reverse removal procedure.DISTRIBUTOR - V8i
Service repair no - 86.35.20
Remove
1.Disconnect battery negative lead.
2.Disconnect vacuum hose.
3.Remove distributor cap.
4.Disconnect low tension lead from coil.
5.Mark distributor body and centre line of rotor
arm.
6.Add alignment marks to distributor and front
cover.
NOTE: Marking distributor enables
refitting in exact original position, but if
engine is turned while distributor is
removed, complete ignition timing procedure
must be followed.
7.Release distributor clamp and remove
distributor.

86ELECTRICAL
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REPAIR Refit
NOTE: If a new distributor is being fitted,
mark body in same relative position as
distributor removed.
8.Leads for distributor cap should be connected as
illustrated.
Figures 1 to 8 inclusive indicate plug lead
numbers.
RH-Right hand side of engine, when viewed
from rear.
LH-Left hand side of engine, when viewed from
rear.
9.If engine has not been turned while distributor
has been removed, carry out instructions 10. to
17. Alternatively proceed to instruction 18.
10.Fit new 'O' ring seal to distributor housing.
11.Turn distributor drive until centre line of rotor arm
is 30Ê anti-clockwise from mark made on top
edge of distributor body.
12.Fit distributor in accordance with alignment
markings.
NOTE: It may be necessary to align oil
pump drive shaft to enable distributor
drive shaft to engage in slot.
13.Fit clamp and bolt. Secure distributor in exact
original position.
14.Connect vacuum hose to distributor and low
tension lead to coil.
15.Fit distributor cap.
16.Reconnect battery.
17.Using suitable electronic equipment, set ignition
timing.
See Adjustment, Ignition timing
18.If engine has been turned with distributor
removed, carry out instructions 19 to 30.
19.Set engine-No. 1 piston to static ignition timing
figure
See ENGINE TUNING DATA,
Information, Engine 3.9 V8i
20.Turn distributor drive until rotor arm is
approximately 30Ê anti-clockwise from number
one sparking plug lead position on cap.
21.Fit distributor to engine.
22.Check that centre line of rotor arm is now in line
with number one sparking plug lead on cap.
Reposition distributor if necessary.
23.If distributor does not seat correctly in front
cover, oil pump drive is not engaged. Engage by
lightly pressing down distributor while turning
engine.
24.Fit clamp and bolt, do not tighten.
25.Set ignition timing statically to 6Ê B.T.D.C.
26.Connect vacuum hose to distributor.
27.Fit low tension lead to coil.
28.Fit distributor cap.
29.Reconnect battery.
30.Using suitable electronic equipment set the
ignition timing.
See Adjustment, Ignition
timing

ELECTRICAL
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REPAIR AUTOMATIC GEAR SELECTOR-PANEL BULB
Service repair no - 86.45.40
1.Disconnect battery negative lead.
2.Carefully prise quadrant finisher out of surround.
3.Carefully prise rear of surround away from
centre console.
4.Pull appropriate bulb holder from fitted position.
5.Remove bulb from holder.
Refit
6.Reverse removal procedureSTART INHIBIT / REVERSE LIGHT SWITCH
Service repair no - 44.15.19
Automatic gearbox
Remove
Reverse light switch is an integral part of start inhibitor
switch. It is located on left hand side of gearbox,
accessible from beneath vehicle.
1.Place vehicle on suitable ramp [hoist].
2.Disconnect battery negative lead.
3.Disconnect multi-plug.
4.Release clamp bolt, remove clamp.
5.Remove switch.
Refit
6.Fit a NEW 'O' ring to switch.
7.Reverse removal procedure.