1999 LAND ROVER DISCOVERY ECU

PANEL REPAIRS
REPAIRS 77-2-49
Cross member outer rear panel
(RH/LH section)
In this procedure, the panel body side assembly and
the 'E' post assembly are replaced in conjunction
with either the RH or LH section of the cross member
outer rear panel.
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove 'E' post assembly.

+ PANEL REPAIRS, REPAIRS, 'E' post
assembly.
4.Remove rear folding step.

+ EXTERIOR FITTINGS, REPAIRS,
Rear folding step.
5. LH side: Remove exhaust tailpipe heatshield.
6.Remove relevant wiring.
Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
Refit
1.Fit and secure wiring.
2. LH side: Fit exhaust tailpipe heatshield.
3.Fit rear folding step.

+ EXTERIOR FITTINGS, REPAIRS,
Rear folding step.
4.Fit 'E' post assembly.

+ PANEL REPAIRS, REPAIRS, 'E' post
assembly.
5.Connect leads/multiplug to alternator.
6.Connect battery leads, negative lead last.
Cross member closing rear panel
In this procedure, the cross member outer rear panel
is replaced in conjunction with the cross member
closing rear panel. The cross member rear assembly
can also be replaced, if required.
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove cross member outer rear panel.

+ PANEL REPAIRS, REPAIRS, Cross
member outer rear panel.
4.Remove fuel tank.

+ FUEL DELIVERY SYSTEM - V8,
REPAIRS, Tank - fuel.

+ FUEL DELIVERY SYSTEM - Td5,
REPAIRS, Tank - fuel.
5.Remove 2 rear bolts securing body rear to
chassis.
Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
Refit
1.Fit 2 rear bolts securing body rear to chassis
and tighten to 45 Nm (33 lbf.ft).
2.Fit fuel tank.

+ FUEL DELIVERY SYSTEM - V8,
REPAIRS, Tank - fuel.

+ FUEL DELIVERY SYSTEM - Td5,
REPAIRS, Tank - fuel.
3.Fit cross member rear outer panel.

+ PANEL REPAIRS, REPAIRS, Cross
member outer rear panel.
4.Connect leads/multiplug to alternator.
5.Connect battery leads, negative lead last.

PANEL REPAIRS
REPAIRS 77-2-51
Rear floor complete assembly
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove loadspace carpet.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Carpet - loadspace.
4.Remove rear seats.

+ SEATS, REPAIRS, Seat - rear.
5.Remove rear carpet.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Carpet - rear.
6.Remove rear bumper assembly.

+ EXTERIOR FITTINGS, REPAIRS,
Bumper assembly - rear - up to 03MY.
7.Remove RH and LH mud flap and brackets.
8.Remove exhaust tail pipe heatshields.
9.Remove tread plates from rear door apertures.
10.Remove rear door aperture seal.
11.Remove tail door tread plate.
12.Remove loadspace carpet retainer.
13.Remove head lining rear trim finisher.
14.Remove tail door aperture seal.
15.Remove bolts securing body to chassis.
16.Remove relevant wiring from floor area.Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
M77 1712A
M77 1721A

PANEL REPAIRS
77-2-52 REPAIRS
Refit
1.Position and secure wiring.
2.Fit and tighten bolts securing body to chassis to
45 Nm (33 lbf.ft).
3.Fit tail door aperture seal.
4.Fit head lining rear trim finisher.
5.Fit loadspace carpet retainer.
6.Fit tail door tread plate.
7.Fit rear door aperture seals.
8.Fit tread plate to rear door apertures.
9.Fit exhaust tail pipe heatshields.
10.Fit mud flap bracklets and mud flaps.
11.Fit rear bumper assembly.

+ EXTERIOR FITTINGS, REPAIRS,
Bumper assembly - rear - up to 03MY.
12.Fit rear carpet.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Carpet - rear.
13.Fit rear seats.

+ SEATS, REPAIRS, Seat - rear.
14.Fit loadspace carpet.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Carpet - loadspace.
15.Connect leads/multiplug to alternator.
16.Connect battery leads, negative lead last.
Rear floor (rear section)
In this procedure, the cross member rear assembly,
cross member outer rear panel, cross member
closing rear panel, 'E' post assembly, 'E' post closing
assembly and the panel body side assembly are
replaced in conjunction with the rear floor (rear
section).
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove cross member rear assembly.

+ PANEL REPAIRS, REPAIRS, Cross
member rear assembly.
4.Remove mud flap mounting brackets.
5. LH side: Remove exhaust heatshield from rear
floor.
Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown. Welds for RH side are symmetrically
opposite to those shown.
Refit
1. LH side: Fit exhaust heatshield to rear floor.
2.Fit mud flap mounting brackets.
3.Fit cross member rear assembly.

+ PANEL REPAIRS, REPAIRS, Cross
member rear assembly.
4.Connect leads/multiplug to alternator.
5.Connect battery leads, negative lead last.

PANEL REPAIRS
77-2-54 REPAIRS
Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
2. During welding operations, apply 'Heat
shrink paste' to roof and body side panel to
avoid heat damage to paintwork.Refit
1.Fit and secure wiring.
2.Fit side and rear drip rail finishers.
3.Fit alpine light glass.

+ SCREENS, REPAIRS, Glass - alpine
light.
4.Fit windscreen.

+ SCREENS, REPAIRS, Windscreen.
5.Fit 'D' post outer trim finishers.
6.Fit rear door aperture seals.
7.Fit tread plates to rear door apertures.
8.Fit front door aperture seals.
9.Fit 'A' post lower trim panels.
10.Fit tread plates to front door apertures.
11.Fit roof bars.

+ EXTERIOR FITTINGS, REPAIRS,
Roof bars.
12.Fit rear headrests.
13.Fit rear seats.

+ SEATS, REPAIRS, Seat - rear.
14.Fit front seats.

+ SEATS, REPAIRS, Seat - front.
15. Models with fixed roof: Fit head lining.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Headlining.
16. Models with sunroof: Fit sunroof drain tubes.
17. Models with sunroof: Fit rear sunroof.

+ SUNROOF, REPAIRS, Sunroof -
rear.
18. Models with sunroof: Fit front sunroof.

+ SUNROOF, REPAIRS, Sunroof -
front.
19.Connect leads/multiplug to alternator.
20.Connect battery leads, negative lead last.
M77 1715A

HEATING AND VENTILATION
80-8DESCRIPTION AND OPERATION
Control panel
The controls for heating and ventilation are installed on a control panel in the centre of the fascia, below the radio.
Three rotary knobs control the LH and RH outlet temperatures and distribution. A slider switch controls blower speed.
A latching pushswitch controls the selection of fresh/recirculated air; an amber LED in the switch illuminates when
recirculated air is selected.
Graphics on the panel and the controls indicate the function and operating positions of the controls.
Outlet vent
The outlet vent promotes the free flow of heating and ventilation air through the cabin. The outlet vent is installed in
the RH rear quarter body panel and vents cabin air into the sheltered area between the rear quarter body panel and
the outer body side panel. The vent consists of a grille covered by soft rubber flaps and is effectively a non-return
valve. The flap opens and closes automatically depending on the differential between cabin and outside air pressures.
FBH system (diesel models only)
The FBH system is an auxiliary heating system that compensates for the relatively low coolant temperatures inherent
in the diesel engine. At low ambient temperatures, the FBH system heats the coolant supply to the heater assembly,
and maintains it within the temperature range required for good in-car heating performance. Operation is fully
automatic, with no intervention required by the driver.
The system consists of an air temperature sensor, a FBH fuel pump and a FBH unit. Fuel for the FBH system is taken
from the fuel tank, through a line attached to the fuel tank's fuel pump, and supplied via the FBH fuel pump to the FBH
unit. The connection on the fuel tank's fuel pump incorporates a tube which extends down into the tank. At the FBH
unit connection, the fuel line incorporates a self-sealing, quick disconnect coupling. In the FBH unit, the fuel delivered
by the FBH fuel pump is burned and the resultant heat output is used to heat the coolant. An ECU integrated into the
FBH unit controls the operation of the system at one of two heat output levels, 2.5 kW at part load and 5 kW at full load
Ambient temperature sensor
The ambient temperature sensor controls a power supply from the alternator to the FBH unit. The sensor is installed
on the RH support strut of the bonnet closing panel and contains a temperature sensitive switch that is closed at
temperatures below 5 °C (41 °F) and open at temperatures of 5 °C (41 °F) and above.

HEATING AND VENTILATION
DESCRIPTION AND OPERATION 80-9
FBH fuel pump
The FBH fuel pump regulates the fuel supply to the FBH unit. The FBH fuel pump is installed in a rubber mounting on
the chassis crossmember immediately in front of the fuel tank. The pump is a self priming, solenoid operated plunger
pump, with a fixed displacement of 0.063 ml/Hz. The ECU in the FBH unit outputs a pulse width modulated signal to
control the operation of the pump. When the pump is de-energised, it provides a positive shut-off of the fuel supply to
the FBH unit.
FBH fuel pump nominal operating speeds/outputs
Sectioned view of FBH fuel pump
1Solenoid coil
2Plunger
3Filter insert
4Fuel line connector
5'O' ring seal6Spring
7Piston
8Bush
9Fuel line connector
10Non return valve
The solenoid coil of the FBH fuel pump is installed around a housing which contains a plunger and piston. The piston
locates in a bush, and a spring is installed on the piston between the bush and the plunger. A filter insert and a fuel
line connector are installed in the inlet end of the housing. A non return valve and a fuel line connector are installed
in the fuel outlet end of the housing.
While the solenoid coil is de-energised, the spring holds the piston and plunger in the 'closed' position at the inlet end
of the housing. An 'O' ring seal on the plunger provides a fuel tight seal between the plunger and the filter insert,
preventing any flow through the pump. When the solenoid coil is energised, the piston and plunger move towards the
outlet end of the housing, until the plunger contacts the bush, and draw fuel in through the inlet connection and filter.
The initial movement of the piston also closes transverse drillings in the bush and isolates the pumping chamber at
the outlet end of the housing. Subsequent movement of the piston then forces fuel from the pumping chamber through
the non return valve and into the line to the FBH unit. When the solenoid coil de-energises, the spring moves the piston
and plunger back towards the closed position. As the piston and plunger move towards the closed position, fuel flows
passed the plunger and through the annular gaps and transverse holes in the bush to replenish the pumping chamber.
Operating phase Speed, Hz Output, l/h (US galls/h)
Start sequence 0.70 0.159 (0.042)
Part load 1.35 0.306 (0.081)
Full load 2.70 0.612 (0.163)

HEATING AND VENTILATION
DESCRIPTION AND OPERATION 80-11
Sectioned view of FBH unit
1Combustion air fan
2Burner housing
3ECU
4Heat exchanger
5Burner insert
6Exhaust
7Glow plug/flame sensor8Evaporator
9Coolant inlet
10Circulation pump
11Fuel inlet
12Coolant outlet
13Air inlet
The FBH unit consists of:
lA circulation pump.
lA combustion air fan.
lA burner housing.
lAn ECU/heat exchanger.
lAn air inlet hose.
lAn exhaust pipe.
Circulation pump. The circulation pump is installed at the coolant inlet to the FBH unit to assist the coolant flow through
the FBH unit and the heater assembly. The pump runs continuously while the FBH unit is in standby or active
operating modes. While the FBH unit is inactive, coolant flow is reliant on the engine coolant pump.
Combustion air fan. The combustion air fan regulates the flow of air into the unit to support combustion of the fuel
supplied by the FBH pump. It also supplies the air required to purge and cool the FBH unit. Ambient air is supplied to
the combustion air fan through an air inlet hose containing a sound deadening foam ring.

HEATING AND VENTILATION
80-12DESCRIPTION AND OPERATION
Burner housing. The burner housing contains the burner insert and also incorporates connections for the exhaust
pipe, the coolant inlet from the circulation pump and the coolant outlet to the heater assembly. The exhaust pipe
directs exhaust combustion gases to atmosphere at the bottom of the engine compartment.
The burner insert incorporates the fuel combustion chamber, an evaporator and a glow plug/flame sensor. Fuel from
the FBH fuel pump is supplied to the evaporator, where it evaporates and enters the combustion chamber to mix with
air from the combustion air fan. The glow plug/flame sensor provides the ignition source of the fuel:air mixture and,
once combustion is established, monitors the flame.
ECU/heat exchanger. The ECU controls and monitors operation of the FBH system. Ventilation of the ECU is
provided by an internal flow of air from the combustion air fan. The heat exchanger transfers heat generated by
combustion to the coolant. A sensor in the heat exchanger provides the ECU with an input of heat exchanger casing
temperature, which the ECU relates to coolant temperature and uses to control system operation. The temperature
settings in the ECU are calibrated to compensate for the difference between coolant temperature and the heat
exchanger casing temperature detected by the sensor. Typically: as the coolant temperature increases, the coolant
will be approximately 7 °C (12.6 °F) hotter than the temperature detected by the sensor; as the coolant temperature
decreases, the coolant will be approximately 2 °C (3.6 °F) cooler than the temperature detected by the sensor.