Discovery electrical Manual - part 80

T1

THEFT ALARM SYSTEM (EXCEPT NAS) (300TDI WITH EDC)

26

CIRCUIT DIAGRAM

Z132
Engine Control
Module (ECM)

45

C243

Z163
Theft Alarm Unit

14

C225

BK

B

24

C217

21

Not used

300Tdi with EDC

BS

15

THEFT ALARM SYSTEM (EXCEPT NAS) (300TDI WITH EDC)

T1

27

CIRCUIT DIAGRAM

85

1

Starting and
Charging

Starting and
Charging

Automatic Trans-
mission

Manual Trans-
mission

K137
Starter Solenoid
Relay

Z158
Starter Relay
Diode

X167
Park/Neutral
Position Switch

85

30

C2006

NW

86

30

87

86

87

C2006

BO

BY

S2005

HJ2

10

C105

11

C105

BO

10

C274

Z163
Theft Alarm Unit

S322

5

C323

B

BG

4

C323

BO

R

N

P

2

3

D

NR

Starting and
Charging

1

WR

Automatic Trans-
mission

Manual Trans-
mission

4

C216

1

C157

K136
Starter Solenoid

300Tdi with EDC

S115

1

C159

Z135
Glow Plug Timer
Unit

NR

NR

WR

THEFT ALARM SYSTEM (NAS)

T2

CIRCUIT OPERATION

1

CIRCUIT OPERATION

For 1996 models a vehicle alarm system is available
as original equipment. Three different functions are
integrated into the Theft Alarm System:

1. The main function of the system is to offer easy–

to–use remote locking and unlocking of the vehi-
cle (Central Locking).

2. Anti–Theft System function.

3. Engine Immobilisation function.

NOTE: The Theft Alarm ECU (Z163) is fully
programmable to meet different market
requirements; therefore some of features listed will
vary dependent on vehicle model or territory.

ALARM COMPONENTS

1. Theft Alarm Unit (Z163)

2. Handset Transmitter

3. Lock Actuators (M114, M122, M117, M125,

M132)

4. Alarm Bonnet Switch (X212) (Not on all vehi-

cles!)

5. Right Front Door Key Switch (X202)

6. Door Switches (X150, X118, X142, X163)

7. Rear End Door Switch (X265)

8. Direction Indicator Lamps (Hazard Lamps)

9. Horns (K128, K134)

10. Theft Alarm LED (Included in the Instrument

Cluster (Z142))

CENTRAL LOCKING FUNCTION

Central Locking is controlled by the Theft Alarm Unit
(Z163) and may be locked by using the driver’s door
key, sill button(s) or handset. The vehicle may be
unlocked by using the handset or EKA code.

NOTE: The central door locking system will shut
down for a period of approximately 15 seconds if the
Theft Alarm Unit (Z163) determines that the Lock
Actuators could be overheating.

ANTI–THEFT SYSTEM FUNCTION

The alarm system offers the following forms of
protection:

Perimetric protection against unauthorised ope-
ning of all doors, tailgate, and bonnet.

Engine crank inhibit against unauthorised engine
crank.

Electronic engine immobilisation against unau-
thorised engine start.

NOTE: Perimetric protection is also triggered by the
driver’s door sill switch being lifted and the ignition
switch being turned on.

Perimetric Protection

The system is perimetrically armed whenever the
vehicle is central door locked using the driver’s door
key or the handset.

Theft Alarm Disarming

(Perimetric Mode)

The theft alarm can be disarmed with the handset or
the driver’s door key.

THEFT ALARM SYSTEM (NAS)

T2

CIRCUIT OPERATION

2

PARTIALLY ARMED MODE

The system will enter the “partially armed” mode
whenever one of the following conditions is valid
during theft alarm arming:

a door, tailgate, or bonnet is open.

The engine will be immobilised and cranking is
inhibited. The alarm will sound if ignition is turned to
start position. The alarm will protect the following:

If any of the doors caused partial arming, then
opening the tailgate or bonnet will sound the
alarm.

If the tailgate caused partial arming, then the
opening of any doors or the bonnet will sound
the alarm.

If the bonnet caused partial arming, then the
opening of any doors or tailgate will sound the
alarm. Volumetric protection is also armed.

If two of the above cause partial arming, then the
third is still protected.

If the doors, tailgate or bonnet is subsequently
closed, after a 5 second delay, the system will fully
arm.

ENGINE CRANKING

It is only possible to crank the engine when ignition
is on and the alarm disabled.

HORNS (K128, K134)

When an intrusion is detected the Horns (K128,
K134) will sound and the hazard lamps flash (where
territorial regulations allow) for 30 seconds . The
alarm must be retriggered before the horns (K128,
K134) will sound again.

INERTIA SWITCH

An inertia switch is incorporated in the Theft Alarm
Unit (Z163). If ignition is on and the vehicle receives
an impact sufficient to activate the inertia switch, the
unit will signal to unlock central locking actuators and
flash hazard lights. Central locking will remain
disabled for a period of 0 to 5 minutes. To reset, turn
ignition off and then on after the time period has
elapsed.

ENGINE IMMOBILISATION FUNCTION

The engine will be immobilised whenever the theft
alarm is armed.

The vehicle may only be mobilised by using the
handset or the driver’s door key.

The electronic engine immobilisation is controlled
jointly by the engine management system’s
Electronic Control Module (ECM) (Z132) and the
Theft Alarm Unit (Z163).

When the Theft Alarm Unit (Z163) immobilises the
vehicle, it sends a signal to the ECM. The ECM then
immobilises the engine management system until a
mobilise signal is received from the Theft Alarm Unit
(Z163).