2002 LAND ROVER DISCOVERY cruise control

ENGINE MANAGEMENT SYSTEM - V8
DESCRIPTION AND OPERATION 18-2-67
Function
The cruise control ECU activates the vacuum pump assembly to move the pneumatic actuator. This moves the
throttle to the set speed by adjusting the position of the throttle disc.
Accelerating while cruise control is active
There are three ways of increasing vehicle speed when cruise control is active:
lTemporarily increase vehicle speed (e.g. when overtaking another vehicle).
lIncrease vehicle set speed in 1 mph (1.5 km/h) increments.
lIncrease vehicle set speed.
To temporarily increase vehicle speed press the accelerator pedal until the desired speed is reached. When the
accelerator pedal is released, the vehicle coasts back to the set speed. When it reaches the set speed, cruise control
operation continues.
To increase the vehicle set speed in 1 mph (1.5 km/h) increments, tap the SET+ switch. Each tap on the switch
increases vehicle speed.
To increase the vehicle set speed, press and hold the SET+ switch until the desired set speed is reached.
The vehicle set speed will increase if the following conditions are met:
lThe vehicle is under cruise control operation.
lVehicle speed is between 28 - 125 mph (45 - 200 km/h).
lThe brake pedal is not pressed.
lThe clutch pedal is not pressed (manual gearbox only).
lThe gearbox is not in park, reverse or neutral (automatic gearbox only).
Function
The vehicle responds as follows:
lIf the driver accelerates using the accelerator pedal, vehicle speed increases overriding pneumatic actuator
position. When the driver releases the accelerator pedal, the vehicle returns to the set speed.
lIf the SET+ switch is tapped, the driver increases the stored speed and vehicle speed by 1 mph (1.5 km/h) per
tap on the switch.
lIf the driver presses and holds the SET+ switch, the vehicle speed increases until the SET+ switch is released.
This becomes the new set speed for the cruise control ECU.
Switching off cruise control
Switching off cruise control allows the driver to regain control of vehicle speed. It erases the set road speed from the
cruise control ECU memory.
To switch off cruise control, press the cruise control master switch to the off position.
Function
When the cruise control master switch is turned off, the cruise control ECU switches off power to the vacuum pump
assembly. The vacuum dump valve opens releasing the vacuum in the pneumatic actuator, returning the throttle disc
to driver control via the accelerator pedal.

ENGINE MANAGEMENT SYSTEM - V8
ADJUSTMENTS 18-2-69
ADJUST ME NTS
Cable - throttle
$% 19.20.05
Adjust
1.Loosen outer cable locknuts.
2.Adjust the rear locknut until it is in contact with
the back of the abutment bracket and the
throttle lever is in contact with the inner driven
lever.
3.Ensure that the driven lever remains in contact
with the throttle stop screw, (throttle closed).
4.Tighten cable front nut to lock cable to
abutment bracket.
Cable - cruise control
$% 19.75.11
Adjust
1.Ensure that the throttle cable is correctly
adjusted.

+ ENGINE MANAGEMENT SYSTEM -
V8, ADJUSTMENTS, Cable - throttle.
2.Loosen outer cable locknuts.
3.Adjust the rear locknut to obtain a 0.5 to 1.5
mm (0.019 to 0.060 in) gap, dimension 'A',
between the cruise control cable lever and the
throttle cable driven lever.
4.Tighten cable front locknut.

ENGINE MANAGEMENT SYSTEM - V8
18-2-80 REPAIRS
Throttle Body
$% 19.22.45
Remove
1.Loosen 3 clips securing air intake hose, release
air intake hose and position aside.
Note: Pre 03 MY air intake hose illustrated.
2.Disconnect throttle and cruise control cables
from throttle body. 3.Loosen clip securing breather hose and release
hose.
4.Disconnect multiplug from throttle body.
5.Position a container below the throttle body to
collect coolant spillage.
6.Loosen 2 clips securing coolant hoses to
throttle body and release hoses.
7.Remove 4 bolts securing throttle body to
plenum chamber.
8.Remove throttle body and discard gasket.
Refit
1.Clean plenum chamber and throttle body
mating faces.
2.Using a new gasket, position throttle body, fit
bolts and tighten to 9 Nm (7 lbf.ft).
3.Connect coolant hoses to throttle body and
secure clips.
4.Connect breather hose to throttle body and
secure clip.
M19 2576A
1

ENGINE MANAGEMENT SYSTEM - V8
REPAIRS 18-2-81
5.Connect multiplug to throttle body.
6.Connect throttle and cruise control cables.
l

+ ENGINE MANAGEMENT SYSTEM
- V8, ADJUSTMENTS, Cable - cruise
control.
l

+ ENGINE MANAGEMENT SYSTEM
- V8, ADJUSTMENTS, Cable - throttle.
7.Position air intake hose and secure clips.
8.Top-up cooling system.
Plenum chamber
$% 19.22.46
Remove
1.Remove upper manifold gasket.

+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Gasket - inlet
manifold - upper - Without Secondary Air
Injection.
2.Remove 2 bolts securing throttle cable
abutment bracket and remove bracket.
3.Remove breather hose adaptor.
4.Remove 4 bolts securing plenum chamber to
upper manifold and remove plenum chamber.
5.Collect plenum chamber gaskets.
Refit
1.Clean plenum chamber and upper manifold
mating faces.
2.Using new gaskets, position plenum chamber
fit bolts and tighten to 22 Nm (16 lbf.ft).
3.Fit breather adaptor and tighten to 6 Nm (4.4
lbf.ft).
4.Position throttle cable abutment bracket, fit
bolts and tighten to 9 Nm (7 lbf.ft).
5.Fit upper manifold gasket.

+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Gasket - inlet
manifold - upper - Without Secondary Air
Injection.

ENGINE MANAGEMENT SYSTEM - V8
18-2-84 REPAIRS
5.Fit bolts securing fuel rail to inlet manifold and
tighten to 9 Nm (7 lbf.ft).
6.Connect fuel feed hose to fuel rail.
7.Connect injector harness multiplugs and
secure to fuel rail.
8.Carefully position ignition coil assembly
between inlet manifold and bulkhead.
9.Fit upper manifold.

+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Gasket - inlet
manifold - upper - Without Secondary Air
Injection.
Actuator - cruise control
$% 19.75.05
Remove
1.Release clip and disconnect inner cable from
actuator.
2.Release outer cable from actuator mounting
bracket.
3.Release vacuum hose from actuator.
4.Remove nut, and remove actuator from
mounting bracket.
Refit
1.Position actuator and tighten retaining nut.
2.Connect vacuum hose to actuator.
3.Connect outer cable to mounting bracket.
4.Connect inner cable to actuator.

ENGINE MANAGEMENT SYSTEM - V8
18-2-86 REPAIRS
3.Disconnect multiplug from control unit.
4.Release 3 rubber mounting securing control
unit to mounting bracket and remove control
unit.
Refit
1.Position control unit and secure mountings.
2.Connect multiplug and vacuum hose.
3. If fitted: Fit heat shield, fit nuts and tighten to
10 Nm (7 lbf.ft).
Cable - cruise control
$% 19.75.10
Remove
1.Release clip and disconnect inner cable from
actuator.
2.Release outer cable from actuator mounting
bracket.
3.Loosen cable locknuts, release outer cable
from abutment bracket and retaining clip.
4.Release inner cable from operating lever and
remove cable.
Refit
1.Position cable and connect to operating lever.
2.Position cable to abutment bracket.
3.Position outer cable to actuator mounting
bracket and connect inner cable to actuator.
4.Adjust cruise control cable.

+ ENGINE MANAGEMENT SYSTEM -
V8, ADJUSTMENTS, Cable - cruise control.

ENGINE MANAGEMENT SYSTEM - V8
REPAIRS 18-2-87
Switch - cruise control (on/off)
$% 19.75.30
Remove
1.Carefully remove switch from instrument cowl.
2.Disconnect multiplug and remove switch.
Refit
1.Position new switch and connect multiplug.
2.Carefully push switch into instrument cowl.
Switch - cruise control (set/resume)
$% 19.75.33
Remove
1.Remove the key from the starter switch.
Disconnect both battery leads, negative lead
first. Wait ten minutes before starting work.
2.Remove driver's airbag module.

+ RESTRAINT SYSTEMS, REPAIRS,
Airbag module - drivers.
3.Release remote control switches multiplug and
leads from steering wheel base.
4.Disconnect remote control switches multiplug
from harness.
5.Remove 2 screws securing remote control
switches to steering wheel base.
6.Release and remove remote control switches
from steering wheel.
Refit
1.Fit remote control switches to steering wheel
and secure with screws.
2.Connect remote control switches multiplug to
harness.
3.Secure leads and multiplug to base of steering
wheel.
4.Fit driver's airbag module.

+ RESTRAINT SYSTEMS, REPAIRS,
Airbag module - drivers.

ENGINE MANAGEMENT SYSTEM - V8
18-2-88 REPAIRS
Switch - clutch pedal - cruise control
$% 19.75.34
Remove
1.Remove 3 fasteners and move driver's side
lower closing panel aside.
2.Disconnect multiplug from clutch pedal switch.
3.Remove switch from pedal bracket.
Refit
1.Engage switch fully into pedal bracket location
and connect multiplug.
2.Position lower closing panel and secure with
fasteners.
ECU - Cruise control
$% 19.75.49
Remove
1.Remove fixings securing fascia RH closing
panel and remove panel.
2.Remove 2 fixings and remove 'A' post lower
trim.
3.Remove 2 nuts and remove ECU from studs.
4.Disconnect multiplug from ECU and remove
ECU.
Refit
1.Position new ECU and connect multiplug.
2.Fit ECU to studs and secure with nuts.
3.Fit lower trim panel to 'A' post and secure with
fixings.
4.Fit closing panel and secure with fixings.
5.Programme the ECU using TestBook.