Discovery 2. Manual — part 365

INSTRUMENTS

DESCRIPTION AND OPERATION

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Description

General
The instrument pack consists of four analogue dials, four warning lamp packs and a Liquid Crystal Display (LCD)
odometer.

The four dials are used to indicate:

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Road speed.

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Engine speed.

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Fuel tank level.

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Engine coolant temperature.

The dials are driven by a microprocessor from information received from the serial communication link. Information
input is received as either:

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Digital.

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Analogue.

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Pulse train.

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Pulse Width Modulation (PWM).

The LCD provides information for:

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Odometer.

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Trip distance.

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Selected gear (on vehicles fitted with an automatic gearbox).

A trip reset button is provided to zero the trip display, this button also allows the selection of "miles" or "kilometres"
for the display. A photocell controls the illumination of the LCD, maintaining contrast of the display during ambient light
changes.

Within the four warning lamp packs there are 28 lamps. A long life bulb illuminates the high beam warning lamp and
the rest of the warning lamps are illuminated by Light Emitting Diodes (LED's). All warning lamp legends are invisible
until lit. When lit the symbols are illuminated on a black background.

The warning lamps illuminate in one of four colours. The colour indicates the level of importance to the driver, as
follows:

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Red = warning.

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Amber = caution.

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Green = system operative.

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Blue = main beam operative.

The first warning lamp pack is located in the top left-hand side of the instrument pack and contains the following
warning lamps:

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Traction control warning lamp.

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Transfer box in neutral warning lamp.

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Differential lock warning lamp

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Overspeed warning lamp (activated for gulf market only).

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Brake system warning lamp.

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Hill Descent Control (HDC) information warning lamp.

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Malfunction Indicator Lamp (MIL)/ SERVICE ENGINE SOON warning lamp.

The second warning lamp pack is located in the centre of the instrument pack and contains the following warning
lamps:

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Direction indicator warning lamps.

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High beam warning lamp.

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Anti-lock brake system warning lamp.

INSTRUMENTS

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DESCRIPTION AND OPERATION

The third warning lamp pack is located in the top right-hand side of the instrument pack and contains the following
warning lamps:

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SRS warning lamp.

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SLS off road mode warning lamp.

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Trailer warning lamp.

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Glow plug warning lamp.

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Water in fuel filter warning lamp.

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Seat belt warning lamp.

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Transmission high temperature warning lamp.

The fourth warning lamp pack is located underneath the tachometer of the instrument pack contains the following
warning lamps:

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Oil pressure warning lamp.

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Alternator charge warning lamp.

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HDC fault warning lamp.

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Self Levelling Suspension (SLS) warning lamp.

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Active Cornering Enhancement (ACE) warning lamp.

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Gearbox manual/sport mode warning lamps.

The serial communication link is used to allow information to travel to and from the instrument pack, and it provides
the ability to configure the instrument pack to a specific market. It also allows the instrument pack to be controlled by
TestBook for diagnostics.

There are five market specific variants of the instrument pack:

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United Kingdom (UK).

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North American Specification (NAS).

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Canada.

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Australia.

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Rest Of the World (ROW), Gulf and Japan.

The main difference between the five markets is that the speedometer will indicate road speed in mph as major figures
and km/h as minor figures, km/h as major figures and mph as minor figures or km/h only.

When TestBook is used to diagnose the instrument pack it demands each of the dials and warning lamps to operate
in-turn so a visual check of their operation can be made.

CAUTION: The instrument pack must not be stored on its face side at any time. This is because the dials have
damping fluid within them to ensure smooth operation of the dials' indicator needles. This fluid will leak out.

Speedometer
The speedometer informs the driver of the current vehicle road speed. It has a Liquid Crystal Display (LCD) to show
odometer, trip meter and, on automatic gearbox models, the selected gear. The speedometer will not show speeds
of less than 1.5 mph (2.5 km/h).

There are three different market configurations:

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NAS and UK = mph as major figures km/h as minor figures.

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Canada = km/h as major figures mph as minor figures.

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ROW and Australia = km/h only.

The Self Levelling and Anti-Lock Brake System (SLABS) ECU provides the signal input for the road speed. The signal
is at 8000 pulses per mile (1.6 kilometres).

INSTRUMENTS

DESCRIPTION AND OPERATION

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LCD odometer/trip meter

The LCD has 3 different display elements:

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Odometer.

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Trip meter.

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Selected gear (on vehicles with automatic gearboxes).

The odometer displays units in either miles or kilometres. It has a range from 0 to 999,999 units, only full units are
displayed irrespective of the type of units selected, the display will stop at 999,999 units. TestBook can be used to
reset the odometer. This is allowed only once and must be carried out before 150 miles (240 km) from new, after this
distance the feature is disabled. The odometer may lose up to one km (0.6 miles) when the battery is reconnected,
this is due to the software incorporated into the instrument pack to prevent anyone tampering with the odometer
reading.

The trip meter displays units in either miles or kilometres and has a range of 0.0 to 999.9 units. The display rolls over
from 999.9 to 0.0 units. Units down to one tenth of a mile or one tenth of a kilometre are displayed. The trip meter
displays 0.0 when the battery is reconnected or charged from a discharged state.

A push button located next to the LCD is utilised to reset the trip meter to zero and to change the units from miles to
kilometres. Pressing the button for less than 2 seconds allows the display to reset to zero. Pressing the button for
more than 2 seconds changes the units from miles to kilometres and vice versa. The units will only change for UK,
NAS and Canadian market vehicles.

The selected gear displays when the automatic gearbox is in park, reverse, neutral, drive 3,2,1, by using the letters
or numbers PRND321 in the display.

The data input for the LCD odometer/trip meter is from the SLABS ECU for the distance input and from the BCU for
the gear position. The instrument pack provides the earth path to illuminate the gear position warning lamp.

If a replacement instrument pack is required TestBook must be used to retrieve the odometer reading, so that when
the new instrument pack is fitted the odometer reading can be programmed in.

INSTRUMENTS

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DESCRIPTION AND OPERATION

Tachometer

The tachometer is an integral part of the instrument pack. Located next to the speedometer. it displays engine speed
in revolutions per minute. It is an analogue gauge with a maximum reading of 6000 rev/min.

V8 and diesel variants use the same gauge.

The input for the tachometer is from the ECM. It is a digital signal at 2 pulses per engine revolution. When the ignition
is switched on with the engine not running, the ECM will generates pulses equivalent to 228 rev/min for diagnostic
purposes. The tachometer will not register a reading, as it only indicate engine speeds above 228 rev/min.