1999 LAND ROVER DISCOVERY climate control

ENGINE MANAGEMENT SYSTEM - V8
DESCRIPTION AND OPERATION 18-2-27
There are two types of IAT sensor diagnostic checks:
lThe IAT sensor signal is less than the minimum threshold – the engine has to have been running for longer than
180 seconds, and idle speed control must have been operational for longer than 10 seconds. No fuel cut off is
active. The IAT sensor signal must be less than -35°C (-31°F) for longer than 200 ms.
lThe IAT sensor signal is greater than the maximum threshold – the ECM has to be powered up (engine does not
need to be running), and the signal must be greater than 140°C (284°F) for longer than 200 ms.
If the IAT sensor fails the following fault codes will be produced and can be retrieved by TestBook:
Air intake duct – Gulf models from 2000MY
1Heat reflective insulation2Supplementary air intake duct
The density of the intake air is partly dependent on altitude and temperature. Hot air has a lower density than cold air;
consequently in hot climates, the low air density can result in low power due to low volumetric efficiency.
In order to improve engine performance, Gulf specification models from 2000MY have a secondary air intake duct
which is located under the front left inner wing of the vehicle. Cooler air from the side of the vehicle is routed through
the duct to the air cleaner, where it combines with air entering via the front grille.
In addition to the secondary air duct, the vehicles are fitted with a larger front grille and have larger cooling and
condenser fans.
The MAF/IAT sensor, air cleaner and air cleaner duct are encased in insulation bags to help keep the intake air cool
and so increase the mass of air entering the engine intake manifold.
The air cleaner includes a cyclone filter and also a dump valve in the bottom of the unit. Sand and dust particles which
are carried into the air cleaner with the air flow are automatically expunged via the dump valve.
P code J2012 description Land Rover description
P0112 Intake air temperature circuit low input Intake air temperature signal less than minimum
threshold, after time for exhaust to warm up
P0113 Intake air temperature circuit high input Intake air temperature signal greater than maximum
threshold
M180452
1
2

FUEL DELIVERY SYSTEM - V8
DESCRIPTION AND OPERATION 19-2-5
Fuel tank breather system (all markets except NAS)
The filler tube incorporates a tank vent which allows air and fuel vapour displaced from the tank when filling to vent to
atmosphere via the filler neck. A relief valve in the vent line to the EVAP canister prevents vapour escaping through
the canister during filling. This prevents the customer overfilling the tank and maintains the correct fuel cut-off level.
The filler tube also incorporates an integral Liquid Vapour Separator (LVS). During normal driving excess fuel vapour
is passed via the vent line into the EVAP canister. To prevent the canister from being overloaded with fuel vapour,
especially in hot climates, the vapour is given the opportunity to condense in the LVS. Fuel which condenses in the
LVS flows back into the tank through the ROV's.
A breather spout within the tank controls the tank 'full' height. When fuel covers the spout it prevents fuel vapour and
air from escaping from the tank. This causes the fuel to 'back-up' in the filler tube and shuts off the filler gun. The
position of the spout ensures that when the filler gun shuts off, a vapour space of approximately 10% of the tanks total
capacity remains. This vapour space ensures that Roll Over Valves (ROV's) are always above the fuel level and the
vapour can escape and allow the tank to breathe.
The pressure relief valve fitted in the vent line to the EVAP canister prevents the customer trickle filling the tank.
Trickle filling greatly reduces the vapour space in the tank which in turn affects the tank's ability to breathe properly,
reducing engine performance and safety. When filling the tank, the pressures created are too low to open the pressure
relief valve, preventing the customer from trickle filling the tank. Vapour pressures created during driving are higher
and will open the valve allowing vapour to vent to the EVAP canister.
Four ROV's are welded onto the top surface of the tank. Each ROV is connected by a tube to the main vent line to
the EVAP canister. The ROV's allow fuel vapour to pass through them during normal vehicle operation. In the event
of the vehicle being overturned the valves shut-off, sealing the tank and preventing fuel from spilling from the vent line.
Fuel tank breather system (NAS)
The filler tube incorporates a tank vent which allows air and fuel vapour displaced from the tank when filling to vent to
atmosphere via the filler neck. A filler cap operated valve within the fuel filler neck prevents vapour escaping through
the EVAP canister during filling. This prevents the customer overfilling the tank and maintains the correct fuel cut-off
level.
The filler tube also has an 'L' shaped, stainless steel Liquid Vapour Separator (LVS). During normal driving excess
fuel vapour is passed via the vent line into the EVAP canister. To prevent the canister from being overloaded with fuel
vapour, especially in hot climates, the vapour is given the opportunity to condense in the LVS. Fuel which condenses
in the LVS flows back into the tank via the LVS vent line and through the Roll Over Valves (ROV's).
For NAS vehicles with vacuum type EVAP system leak detection capability, a small tube is located alongside the filler
tube and terminates near to the filler neck. The tube is connected to the On Board Diagnostics (OBD) pressure sensor
in the fuel pump and provides the sensor with a reading of atmospheric pressure to compare against the tank
pressure.

+ EMISSION CONTROL - V8, DESCRIPTION AND OPERATION, Emission Control Systems.
A breather spout within the tank controls the tank 'full' height. When fuel covers the spout it prevents fuel vapour and
air from escaping from the tank. This causes the fuel to 'back-up' in the filler tube and shuts off the filler gun. The
position of the spout ensures that when the filler gun shuts off, a vapour space of approximately 10% of the tanks total
capacity remains. This vapour space ensures that the ROV's are always above the fuel level and the vapour can
escape to the LVS and allow the tank to breathe.
The filler cap operated valve closes the vent line to the EVAP canister to prevent the customer trickle filling the tank.
Trickle filling greatly reduces the vapour space in the tank which in turn affects the tank's ability to breathe properly,
reducing engine performance and safety. When filling the tank, the removal of the filler cap closes the valve and the
vent line preventing the customer from trickle filling the tank. When the cap is installed the valve is opened by the cap
allowing vapour to vent to the EVAP canister.
The four ROV's are welded inside the top surface of the tank. Each ROV is connected internally in the tank by a tube
to the LVS. The ROV's allow fuel vapour to pass through them during normal vehicle operation. In the event of the
vehicle being overturned the valves shut-off, sealing the tank and preventing fuel from spilling from the vent line into
the LVS.

IN CAR ENTERTAINMENT
86-6-18 DESCRIPTION AND OPERATION
The console unit has three buttons which allow for minimum operation of the unit without using the handset:
lThe Stop/Eject button stops playback when pressed – 'Stop' appears on the LCD monitor as confirmation.
When the playback is stopped, a further press of the Stop/Eject button ejects the DVD or CD from the DVD
console – 'Eject' appears on the LCD monitor as confirmation.
lThe Play/Pause button begins play of the DVD or CD when pressed – 'Play' appears on the LCD monitor as
confirmation.
During play, pressing the Play/Pause button temporarily pauses the play – 'Pause' appears on the LCD monitor
as confirmation. A second press of the Play/Pause button resumes the play.
lThe Speaker button switches the DVD or CD audio to play through the vehicle audio speakers system. When the
CD is selected on the ICE head unit in the fascia, pressing the button allows the DVD or CD audio to play through
the vehicle audio speakers – 'Speaker On' appears on the LCD monitor. A second press of the button prevents
the DVD or CD audio playing through the vehicle audio speakers – 'Speaker Off' appears on the LCD monitor.
NOTE: These functions are also available from buttons on the remote handset.
Two sockets are provided on the left hand side of the unit and one socket on the right hand side of the unit for the use
of headphones with the overhead console unit. This allows the three occupants of the 2nd row seats to listen to the
DVD output using headphones. Occupants of the 3rd row seats can also listen to the DVD output using headphones
connected into the two radio/headphone amplifier units.
The console has three Phono sockets which allow for the use of an auxiliary video unit or video games console to be
connected to the system and use the LCD monitor for display. The sockets are colour coded for correct auxiliary input
connection as follows:
lRED – Right channel audio input
lWHITE – Left channel audio input
lYELLOW – Video input.
A slot is provided on the right hand side of the console for insertion of a DVD or CD into the console unit. The DVD
or CD can be inserted into the slot with the label side facing upwards. The DVD or CD is ejected from the slot when
the Stop/Eject button is pressed.
When the LCD monitor is in the lowered position, an infra-red receiver is exposed and receives transmitted signals
from the remote control handset. The receiver is located adjacent to the status LED which is illuminated when the
system is active.
The DVD player in the overhead console has an auto eject feature to protect the DVD or CD in the unit from damage
due to excessive heat. The status LED will flash to alert the user to this condition. If the temperature exceeds 70°C
(158°F), the DVD system automatically ejects the DVD or CD and shuts down, preventing further operation. When
the temperature in the vehicle has returned to 64°C (147°F) or less, press the 'Power' button on the handset or open
the LCD monitor to switch on the system.
Liquid Crystal Display (LCD) Monitor
The LCD monitor is suited for use with the in-car DVD system because of its compact, lightweight design and low
power consumption. The LCD monitor is a highly sophisticated unit and should be treated with care. Observe the
following precautions when using or handling the LCD monitor.
lDo not press on the monitor, this can distort the picture and cause permanent damage to the LCD panel.
lClean the LCD panel with a damp soft cloth with a mild household detergent if necessary. DO NOT use solvents,
commercial cleaners or anti-static sprays.
lDo not use the LCD in temperatures below 0°C (32°F) or above 80°C (176°F). If the vehicle is used in a cold
climate or in direct sunlight in a warm climate, the LCD monitor may not function correctly outside of the
temperatures stated. The picture may not be clear. This will not cause permanent damage to the monitor and the
picture should return to normal once the temperature is within the operating range as stated.