fuse box LAND ROVER DISCOVERY 1999 Workshop Manual

GENERAL INFORMATION
03-15
Hose clips
Markings (4) are usually provided on the hose to
indicate the correct clip position. If no markings are
provided, position the clip directly behind the
retaining lip at the end of the stub as shown. Worm
drive clips should be oriented with the crimped side
of the drive housing (5) facing towards the end of the
hose, or the hose may become pinched between the
clip and the stub pipe retaining lip. Worm drive clips
should be tightened to 3 Nm (2 lbf.ft) unless
otherwise stated. Ensure that hose clips do not foul
adjacent components.
Heat protection
Always ensure that heatshields and protective
sheathing are in good condition. Replace if damage
is evident. Particular care must be taken when
routing hoses close to hot engine components, such
as the exhaust manifold and the Exhaust Gas
Recirculation (EGR) pipe. Hoses will relax and
deflect slightly when hot; ensure this movement is
taken into account when routing and securing hoses.
Rolling Road Testing
General
IMPORTANT: Use a four wheel rolling road for
brake testing if possible.
WARNING: Do not attempt to test ABS function
on a rolling road.
Four wheel rolling road
Provided that front and rear rollers are rotating at
identical speeds and that normal workshop safety
standards are applied, there is no speed restriction
during testing except any that may apply to the tyres.
Before testing a vehicle with anti-lock brakes on a
four wheel rolling road, disconnect the ABS
modulator. The ABS function will not work, the ABS
warning light will illuminate. Normal braking will be
available.
Two wheel rolling road
Up to 03MY
ABS will not function on a two wheel rolling road. The
ABS light will illuminate during testing. Normal
braking will be available.
If brake testing on a two wheel rolling road is
necessary, the following precautions should be
taken:
lPropeller shaft to the rear axle is removed.
lNeutral selected in gearbox.
When checking brakes, run engine at idle speed to
maintain servo vacuum.
From 03MY
The differential lock must be engaged for two wheel
rolling road testing. It will also be necessary to
disconnect the propeller shaft from the transfer box
output shaft driving the axle whose wheels are NOT
on the rolling road. Additionally, the ETC system
must be deactivated by either removing the 10 amp
fuse (Number 28, labelled ABS in the main fuse box)
or disconnecting the ABS modulator pump. This
must be done with the ignition OFF ; a fault in the
ABS system may still be recorded.
WARNING; VEHICLES NOT FITTED WITH A
DIFFERENTIAL LOCK MUST NOT BE TESTED
ON A ROLLING ROAD WHERE THE ROLLERS
ARE DRIVEN BY THE VEHICLE.

ENGINE - V8
REPAIRS 12-2-27
11.Remove bolt securing oil cooling pipes to PAS
pump housing and remove saddle clamp.
12.Release PAS pump high and low pressure
pipes and position aside.
CAUTION: Always fit plugs to open
connections to prevent contamination.
13.Release clips securing hose to coolant pump
and coolant rail, release hose and position
aside.
14.Release 2 harness clips from coolant rail.
15.Remove bolt securing coolant rail and position
rail aside. 16.Remove bolt securing engine earth lead and
position earth lead aside.
17.Remove nut securing engine harness positive
lead to battery, release lead and position
aside.
18.Release clips and remove fuse box cover.
19.Remove bolt securing starter lead to fuse box,
release lead and position aside.
20.Disconnect 2 engine harness multiplugs from
fuse box.

ENGINE - V8
12-2-30 REPAIRS
Refit
1.Clean mating faces of engine and gearbox,
dowel and dowel holes.
2.Lubricate splines and bearing surface on first
motion shaft with grease.
3.With assistance position engine in engine bay,
align to gearbox and locate on dowels.
4.Position support brackets, fit bell housing bolts
and tighten to 50 Nm (37 lbf.ft).
5.Position engine mountings, fit nuts and tighten
to 85 Nm (63 lbf.ft).
6.Lower lifting equipment and remove from
engine.
7. Models with automatic gearbox: Align torque
converter to drive plate, fit bolts and tighten to
50 Nm (37 lbf.ft). Fit access plug.
8.Fit exhaust front pipe.

+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Front pipe.
9.Position oil cooling pipe saddle clamps and
tighten bolts.
10.Position engine harness into foot well.
11.Connect 5 multiplugs to ECM.
12.Fit toe board and secure with trim fixings.
13.Connect engine harness earth to body and
secure with nut.
14.Connect engine harness to main harness
multiplug.
15.Connect multiplug to EVAP purge valve.
16.Connect engine harness multiplugs to fuse
box.
17.Connect starter lead to fuse box and secure
with nut.
18.Connect engine harness positive lead to
battery and tighten nut.
19.Fit fuse box cover.
20.Position engine earth lead and secure with
bolt.
21.Position coolant rail and secure with bolt.
22.Connect harness clips to coolant rail.
23.Connect hose to coolant rail and coolant pump
and secure with clips.
24.Connect PAS pump high and low pressure
pipes and secure with clips.
25.Position oil cooling pipe saddle clamp to PAS
pump housing and secure with bolt.
26.Clean A/C compressor and housing mating
faces, dowels and dowel holes.
27.Position A/C compressor, fit bolts and tighten
to 22 Nm (16 lbf.ft).
28.Connect multiplug to A/C compressor.
29.Clean ACE pump and housing mating faces,
dowels and dowel holes.
30.Position ACE pump, fit bolts and tighten to 22
Nm (16 lbf.ft). 31.Clean all pulley 'V's, fit auxiliary drive belt,
using a 15mm spanner, release belt tensioner
secure belt and re-tension drive belt .
32.Ensure auxiliary drive belt is correctly located
on all pulleys.
33.Fit radiator.

+ COOLING SYSTEM - V8, REPAIRS,
Radiator.
34.Fit top hose and secure with clips.
35.Connect fuel pipe to fuel rail.
36.Position ignition coils and connect ht leads.
37.Fit upper inlet manifold.

+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Gasket - inlet
manifold - upper - Without Secondary Air
Injection.
38.Fit new oil filter and refill engine with oil.

+ ENGINE - V8, REPAIRS, Filter - oil.

+ MAINTENANCE, PROCEDURES,
Engine oil - V8 engine.
39.Top up gearbox oil.

+ MAINTENANCE, PROCEDURES,
Automatic gearbox.

EMISSION CONTROL - V8
DESCRIPTION AND OPERATION 17-2-5
Evaporative emission system control
diagram
1Battery
2Fuse 13 (engine compartment fusebox)
3Inertia switch
4Main relay (engine compartment fusebox)
5Engine Control Module (ECM)
6Purge Valve (black harness connector)
7Canister vent solenoid (CVS) valve – NAS
vehicles with vacuum type EVAP system leak
detection capability only8Leak detection pump – NAS vehicles with
positive pressure type EVAP system leak
detection capability only
9Fuel tank pressure sensor – NAS vehicles with
vacuum type EVAP system leak detection
capability only
10Instrument pack (MIL warning light)
M17 0210
12
3
4
5
6
7
9
8
10

EMISSION CONTROL - V8
17-2-8 DESCRIPTION AND OPERATION
Secondary air injection system control
diagram
1Fuselink 2 (engine compartment fusebox)
2SAI pump relay
3SAI pump
4SAI vacuum solenoid valve
(grey harness connector)5Engine Control Module (ECM)
6Battery
7Fuse 13 (engine compartment fusebox)
8Inertia switch
9Main relay
9
M17 0207
1
2
3
4
5
7
6
8

EMISSION CONTROL - V8
17-2-14 DESCRIPTION AND OPERATION
The heated oxygen sensor is screwed into threaded mountings welded into the top of the front exhaust pipes at
suitable locations. They are used to detect the level of residual oxygen in the exhaust gas to provide an instantaneous
indication of whether combustion is complete. By positioning sensors in the stream of exhaust gases from each
separate bank of the exhaust manifold, the engine management system is better able to control the fuelling
requirements on each bank independently of the other, so allowing much closer control of the air:fuel ratio and
optimising catalytic converter efficiency.
Two pre-catalytic converter heated oxygen sensors are mounted in the front pipes for monitoring the oxygen content
of the exhaust gas. NAS models also have two additional post-catalytic converter heated oxygen sensors in the
exhaust front pipe.
CAUTION: HO2 sensors are easily damaged by dropping, over torquing, excessive heat or contamination.
Care must be taken not to damage the sensor housing or tip.
The oxygen sensors consist of a ceramic body (Galvanic cell) which is a practically pure oxygen-ion conductor made
from a mixed oxide of zirconium and yttrium. The ceramic is then coated with gas-permeable platinum, which when
heated to a sufficiently high temperature (≥ 350° C) generates a voltage which is proportional to the oxygen content
in the exhaust gas stream.
The heated oxygen sensor is protected by an outer tube with a restricted flow opening to prevent the sensor's
ceramics from being cooled by low temperature exhaust gases at start up. The post-catalytic sensors have improved
signal quality, but a slower response rate.
The pre-catalytic and post-catalytic converter sensors are not interchangeable, and although it is possible to mount
them in transposed positions, their harness connections are of different gender and colour. It is important not to
confuse the sensor signal pins; the signal pins are gold plated, whilst the heater supply pins are tinned,
mixing them up will cause contamination and adversely affect system performance.
Each of the heated oxygen sensors have a four pin connector with the following wiring details:
lSensor signal ground (grey wire – connects to engine management ECM)
lSensor signal (black wire – connects to engine management ECM)
lHeater drive (white wire – connects to engine management ECM)
lHeater supply (white wire – connects to fuse 2, underbonnet fuse box)
The ECM connector pins for exhaust emission control are listed in the following table:
ECM Connector 2 (C635) pin-out details for exhaust emission control system
The heated oxygen sensors should be treated with extreme care, since the ceramic material within them can be easily
cracked if dropped, banged or over-torqued; the sensors should be torqued to the recommended values indicated in
the repair procedures. Apply anti-seize compound to the sensor's threads when refitting.
WARNING: Some types of anti-seize compound used in service are a health hazard. Avoid skin contact.
WARNING: To prevent personal injury from a hot exhaust system, do not attempt to disconnect any
components until the exhaust system has cooled down.
CAUTION: Do not allow anti-seize compound to come into contact with tip of sensor or enter exhaust system.
NOTE: A new HO2 sensor is supplied pre-treated with anti-seize compound.
Pin Number Function Signal Type Control
2-01 Post-cat sensor heater (RH) - NAS only Output, Drive PWM, 12 - 0V
2-07 Post-cat sensor heater (LH) - NAS only Output, Drive PWM, 12 - 0V
2-08 Post-cat sensor (RH) - NAS only Ground, Signal 0V
2-09 Pre-cat sensor (LH) Ground, Signal 0V
2-10 Pre-cat sensor (RH) Ground, Signal 0V
2-11 Post-cat sensor (LH) - NAS only Ground, Signal 0V
2-13 Pre-cat sensor heater (RH) Output, Drive PWM, 12 - 0V
2-14 Post-cat sensor (RH) - NAS only Input, Signal Analogue, 0 - 1V
2-15 Pre-cat sensor (LH) Input, Signal Analogue, 0 - 1V
2-16 Pre-cat sensor (RH) Input, Signal Analogue, 0 - 1V
2-17 Post-cat sensor (LH) - NAS only Input, Signal Analogue, 0 - 1V
2-19 Pre-cat sensor heater (LH) Output, Drive PWM, 12 - 0V

EMISSION CONTROL - V8
17-2-20 DESCRIPTION AND OPERATION
For NAS vehicles with positive pressure, EVAP system leak detection capability, the atmosphere vent line from the
EVAP canister connects to a port on the fuel leak detection pump via a short, large bore hose which is secured to the
component ports by crimped metal clips at each end. A large bore plastic hose from the top of the leak detection pump
is routed to the RH side of the engine bay where it connects to an air filter canister. Under normal operating conditions
(when the fuel leak detection solenoid valve is not energised), the EVAP canister is able to take in clean air via the
air filter, through the pipework and past the open solenoid valve to allow normal purge operation to take place and
release any build up of EVAP system pressure to atmosphere.
The EVAP system pipes are clipped at various points along the pipe runs and tied together with tie straps at suitable
points along the runs.
The NAS and ROW EVAP canisters are of similar appearance, but use charcoal of different consistency. The ROW
vehicles use granular charcoal of 11 bwc (butane working capacity) and NAS vehicles use pelletised charcoal with a
higher absorption capacity of 15 bwc. All canisters are of rectangular shape and have capacities of 1.8 litres (3 1/8
imp. pts) with purge foam retention.
Purge Valve
1Direction of flow indicator
2Inlet port – from EVAP canister3Outlet port – to inlet manifold
4Integral electrical connector
The EVAP canister purge valve is located in the engine bay at the LH side of the engine intake manifold. The valve
is held in position by a plastic clip which secures the inlet pipe of the purge valve to a bracket mounted at the rear of
the engine compartment. On vehicles with secondary air injection, the purge valve is fixed to a metal bracket together
with the SAI vacuum solenoid valve; the purge valve is fixed to the bracket by two plastic clips.
A nylon pipe connects the outlet of the purge valve to the stub pipe on the plenum chamber via a short rubber hose.
The connector to the plenum chamber is a quick-release type, plastic 90° female elbow; the connection is covered by
a rubber seal which is held in position on the port stub pipe.
A service port is connected in line between the EVAP canister and the inlet side of the purge valve and is rated at 1
psi maximum regulated pressure. The service port must be mounted horizontally and is located close to the bulkhead
at the rear of the engine bay. The service point is used by dealers for pressure testing using specialist nitrogen test
equipment for localising the source of small leaks.
The purge valve has a plastic housing, and a directional arrow is moulded onto the side of the casing to indicate the
direction of flow. The head of the arrow points to the outlet side of the valve which connects to the plenum chamber.
Purge valve operation is controlled by the engine control module (ECM). The purge valve has a two-pin electrical
connector which links to the ECM via the engine harness. Pin-1 of the connector is the power supply source from fuse
2 in the engine compartment fusebox, and pin-2 of the connector is the switched earth from the ECM (pulse width
modulated (PWM) signal) which is used to control the purge valve operation time. Note that the harness connector
for the purge valve is black, and must not be confused with the connector for the Secondary Air Injection
vacuum solenoid valve which is grey.
When the purge valve is earthed by the ECM, the valve opens to allow hydrocarbons stored in the EVAP canister to
be purged to the engine inlet manifold for combustion.

EMISSION CONTROL - V8
DESCRIPTION AND OPERATION 17-2-21
If the purge valve breaks or becomes stuck in the open or closed position, the EVAP system will cease to function
and there are no default measures available. The ECM will store the fault in memory and illuminate the MIL warning
lamp if the correct monitoring conditions have been achieved (i.e. valve status unchanged for 45 seconds after engine
has been running for 15 minutes). If the purge valve is stuck in the open position, a rich air:fuel mixture is likely to
result at the intake manifold, this could cause the engine to misfire and the fuelling adaptions will change.
The following failure modes are possible:
lSticking valve
lValve blocked
lConnector or harness wiring fault (open or short circuit)
lValve stuck open
If the purge valve malfunctions, the following fault codes may be stored in the ECM diagnostic memory, which can be
retrieved using TestBook/T4:
Canister Vent Solenoid (CVS) Unit – (NAS with vacuum type, fuel evaporation leak detection system only)
1CVS unit
2Mounting bracket3Spring clips to pipe from EVAP canister
4Harness connector
The canister vent solenoid (CVS) valve is mounted on a slide-on bracket which is riveted to the cruise control bracket
at the right hand side of the engine compartment. The vent pipe from the EVAP canister is connected to a stub pipe
on the CVS unit via a hose and plastic pipe combination. A two-pin connector links to the engine management ECM
via the engine harness for solenoid control; one of the wires is the supply feed from fuse No.2 in the engine
compartment fusebox, the other wire is the valve drive line to the ECM. The solenoid is operated when the ECM
grounds the circuit.
P-code Description
P0440Purge valve not sealing
P0444Purge valve open circuit
P0445Purge valve short circuit to ground
P0443Purge valve short circuit to battery voltage

EMISSION CONTROL - V8
17-2-24 DESCRIPTION AND OPERATION
Leak Detection Pump (NAS vehicles with positive pressure EVAP system leakage test only)
1Harness connector
2Leak detection pump motor
3Atmosphere connection to/from EVAP canister4Atmosphere connection to/from air filter
5Leak detection pump solenoid valve
The fuel evaporation leak detection pump is mounted forward of the EVAP canister on a bracket fitted beneath the
vehicle on the RH side of the vehicle chassis. The leak detection pump is fixed to the bracket by three screws through
the bottom of the bracket.
A short hose connects between the atmosphere vent port of the EVAP canister and a port at the rear of the fuel
evaporation leak detection pump. The hose is secured to the ports at each end by crimped metal band clips.
An elbowed quick fit connector on the top of the fuel evaporation leak detection pump connects to atmosphere via a
large bore pipe. The pipe is routed along the underside of the vehicle chassis and up into the RH side of the engine
compartment where it connects to an air filter canister.
The leak detection pump incorporates a 3–pin electrical connector. Pin-1 is the earth switched supply to the ECM for
control of the pump solenoid valve. Pin-2 is the earth switched supply to the ECM for the operation of the pump motor.
Pin-3 is the power supply to the pump motor and solenoid valve and is switched on at system start up via the main
relay and fuse 2 in the engine compartment fusebox.
Under normal circumstances (i.e. when the leak detection pump is not operating and the solenoid is not energised),
the EVAP canister vent port is connected to atmosphere via the open solenoid valve.
The pump is operated at the end of a drive cycle when the vehicle is stationary and the ignition is switched off.
The leak detection pump module contains an integral air by-pass circuit with restrictor (reference-leak orifice) which
is used for providing a reference value for the leak detection test. The restrictor corresponds to an air leak equivalent
to 0.5 mm (0.02 in) diameter. With the solenoid valve open and the purge valve closed, the pump forces pressurised
air through the orifice while the current drawn by the leak detection pump motor is monitored to obtain the reference
value. The orifice must be kept free from contamination, otherwise the reference restriction may appear less than for
a 0.5 mm leak and consequently adversely affect the diagnostic results.
M17 0213
3
4
5
1
2

EMISSION CONTROL - V8
17-2-28 DESCRIPTION AND OPERATION
The air delivery pipe is a flexible plastic type, and is connected to the air pump outlet via a plastic quick-fit connector.
The other end of the flexible plastic pipe connects to the fixed metal pipework via a short rubber hose. The part of the
flexible plastic pipe which is most vulnerable to engine generated heat is protected by heat reflective sleeving. The
metal delivery pipe has a fabricated T-piece included where the pressurised air is split for delivery to each exhaust
manifold via the SAI control valves.
The pipes from the T-piece to each of the SAI control valves are approximately the same length, so that the pressure
and mass of the air delivered to each bank will be equal. The ends of the pipes are connected to the inlet port of each
SAI control valve through short rubber hose connections.
The T-piece is mounted at the rear of the engine (by the ignition coils) and features a welded mounting bracket which
is fixed to the engine by two studs and nuts.
The foam filter in the air intake of the SAI pump provides noise reduction and protects the pump from damage due to
particulate contamination. In addition, the pump is fitted on rubber mountings to help prevent noise which is generated
by pump operation from being transmitted through the vehicle body into the passenger compartment.
If the secondary air injection (SAI) pump is found to be malfunctioning, the following fault codes may be stored in the
ECM diagnostic memory, which can be retrieved using Testbook/T4:
NOTE: Refer to 'SAI System Fault Finding' and 'Checking Malfunctions on SAI System' at the end of this section to
determine root cause of fault codes.
NOTE: The electrical test of the SAI pump powerstage only indicates that there is a problem with the relay or the
power supply to the relay. It does not indicate the state of the SAI pump itself (i.e. broken or not connected).
As a result of a SAI pump powerstage malfunction, other fault codes may also become stored in the ECM memory.
These may include the following P codes.
NOTE: A malfunction of the SAI pump powerstage is logically expected to result in both engine banks reporting the
same fault.
NOTE: Refer to 'SAI System Fault Finding' and 'Checking Malfunctions on SAI System' at the end of this section to
determine root cause of fault codes.
Secondary Air Injection (SAI) Pump Relay
The secondary air injection pump relay is located in the engine compartment fusebox. The engine control module
(ECM) is used to control the operation of the SAI pump via the SAI pump relay. Power to the coil of the relay is supplied
from the vehicle battery via the main relay and the ground connection to the coil is via the ECM.
Power to the SAI pump relay contacts is via fusible link FL2 which is located in the engine compartment fusebox.
P-code Description
P0418Secondary Air Injection System – Relay 'A' circuit malfunction (SAI pump
powerstage fault, e.g. - SAI pump relay fault or relay not connected / open circuit /
harness damage).
P-code Description
P1412Secondary Air Injection System – Malfunction Bank 1 LH (Insufficient SAI flow
during passive test)
P1414Secondary Air Injection System – Low air flow Bank 1 LH (Insufficient SAI flow
during active test)
P1415Secondary Air Injection System – Malfunction Bank 2 RH (Insufficient SAI flow
during passive test)
P1417Secondary Air Injection System – Low air flow Bank 2 RH (Insufficient SAI flow
during active test)