This document provides information about a vehicle theft alarm system, including: - General descriptions of how the system arms, disarms, and responds to unauthorized access attempts. - Instructions for performing self-diagnosis tests to check the operation of sensors and circuits. - Procedures for technicians to remove and install the VTA module, which involves removing various dash panel components. - Steps for technicians to diagnose the system using the self-diagnosis mode and by checking for proper horn responses from sensors.

1. ZJ VEHICLE THEFT ALARM 8Q - 1
VEHICLE THEFT ALARM
CONTENTS
page page
DIAGNOSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 SERVICE PROCEDURES ................... 6
GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1
GENERAL INFORMATION
The Vehicle Theft Alarm (VTA) system is an avail- DISARMING
able option on Grand Cherokee models. This system Passive disarming occurs upon normal vehicle en-
is designed to protect against vehicle theft by moni- try (unlocking either front door or liftgate, with the
toring vehicle doors, hood, liftgate and ignition action key). This disarming also will halt the alarm, once it
for unauthorized operation. When unauthorized oper- has been activated.
ation is detected, the VTA system responds by sound- Active disarming occurs when the remote keyless
ing the horn, flashing the headlamps, park and tail entry transmitter is used to unlock the vehicle doors.
lamps and providing an engine no-run feature. Fol-
This disarming also will halt the alarm, once it has
lowing are general descriptions of the features of the
been activated.
VTA system. Refer to Group 8W - Wiring Diagrams
for complete circuit descriptions and diagrams.
POWER-UP MODE
ARMING When the battery is disconnected and then recon-
Passive arming occurs upon normal vehicle exit (ig- nected, or when the battery has been drained and
nition OFF, open door, lock with power lock switch, the vehicle is being jump started, the VTA system en-
close door). The alarm system will not arm if the ters its power-up alarm mode which:
doors are manually locked, providing a manual over- • flashes the headlamps
ride of alarm. • flashes the park and tail lamps
Active arming occurs when the remote keyless en- • prevents the engine from running.
try transmitter is used to lock the vehicle doors, The alarm system must be actively or pas-
whether the doors are open or closed. If one or more sively disarmed to exit the power-up mode after
doors are open, the arming sequence is completed any battery reconnection.
only after all doors and the liftgate are closed.
After active or passive arming, the security lamp in TAMPER ALERT
the instrument panel will flash for 15 seconds, show- A tamper alert feature notifies the driver that the
ing that arming is in progress. Note that this 15 sec- alarm had been activated, and has since timed-out
ond arming period will start after the illuminated (alarmed for more than 18 minutes). This alert gives
entry system has timed out (courtesy lamps off). If no 3 horn pulses when the system is actively or pas-
monitored systems are activated during this period, sively disarmed.
the system will arm.
If the hood switch is not seen by the system, the ON-BOARD DIAGNOSTIC SYSTEM
security lamp will remain steadily lit during the The DRB scan tool may be used to test the VTA
arming process. While the system will still arm, the system. Refer to the appropriate Diagnostic Proce-
engine compartment will not be protected from entry dures manual for more information.
when the security lamp remains steadily lit during
the arming process.

2. 8Q - 2 VEHICLE THEFT ALARM ZJ
DIAGNOSIS
SELF-DIAGNOSIS (4) Rotate the key in each door lock cylinder to the
A self-diagnosis mode is available in the VTA sys- lock position, then to the unlock position. The horn
tem to verify operation of all monitored switches or will sound as the switch closes, and again when it
circuits. To enter this mode, cycle the ignition switch opens. There must be a 1 second delay between
ACCESSORY-OFF-ACCESSORY-OFF-ACCESSORY, changing switch states, or the horn will not sound.
leaving the switch in the ACCESSORY position. (5) Activate the remote keyless entry in both the
Upon entering the self-diagnosis mode the head- lock and unlock directions. The horn will sound after
lamps, park and tail lamps will begin flashing to ver- each activation.
ify their operation. In addition, the horn will sound (6) Cycle the ignition key to the ignition switch ON
twice. Returning the ignition to the OFF position will position. A single horn pulse will indicate proper op-
stop the lamps from flashing while keeping the sys- eration of the ignition input. This also will take the
tem in the diagnostic mode. module out of the diagnostic mode.
Also note that vehicles equipped with VTA are The lack of a horn pulse response to any of the
equipped with the illuminated entry system. When in above tests indicates:
the diagnostic mode it is recommended that the illu-
• a switch failure
minated entry relay be removed. Otherwise, it is nec-
• an open or shorted circuit between the switch and
essary to wait 30 second for the illuminated entry
the VTA module
system to time out after each door opening or clo-
• an internal VTA module failure.
sure.
While in the diagnostic mode, a horn pulse should Check for continuity at the switch. If OK, check for
occur at each of the following events indicating an open or shorted wire between the switch and VTA
proper operation. However, if a switch is cycled too module. Also, check if the powertrain control module
quickly and does not remain open or closed for at (PCM) has been replaced recently. For the first 20
least 1 second, the horn will not sound to confirm op- engine starts with a new PCM, the VTA will function
eration. normally except for the engine no-run feature.
(1) Beginning with all doors closed, open then close A PCM from a vehicle equipped with VTA can-
each door. The horn will sound when the door jamb not be used in a vehicle that is not equipped
switch closes, and again when the switch opens. with VTA.
There must be a 1 second delay between closing and If the security lamp comes on after ignition
opening the switch. ON and stays on, the CCD bus communication
(2) Open, then close the hood. The horn will sound with the PCM has been lost.
when the hood is opened, and again when it is closed.
(3) Activate the power door locks in both the lock
and unlock directions. The horn will sound after each
activation.

3. ZJ VEHICLE THEFT ALARM 8Q - 3
VEHICLE THEFT ALARM DIAGNOSIS

4. 8Q - 4 VEHICLE THEFT ALARM ZJ
VEHICLE THEFT ALARM DIAGNOSIS (CONTINUED)

5. ZJ VEHICLE THEFT ALARM 8Q - 5
VEHICLE THEFT ALARM DIAGNOSIS (CONTINUED)

6. 8Q - 6 VEHICLE THEFT ALARM ZJ
SERVICE PROCEDURES
VTA MODULE REMOVE/INSTALL (9) Remove 3 screws above instrument panel clus-
(1) Disconnect battery negative cable. ter holding dash pad (Fig. 3).
(2) Remove ash receiver.
(3) Remove 6 screws holding center cluster bezel
(Fig. 1).
Fig. 3 Remove Screws Holding Dash Pad
(10) Open glove box and remove 2 screws holding
dash pad (Fig. 4).
Fig. 4 Remove Screws Holding Dash Pad
Fig. 1 Remove Center Bezel Retaining Screws
(11) Remove dash pad prying gently on each end to
(4) Remove center bezel. unsnap end clips.
(5) Remove 2 screws holding dash pad located be- (12) Remove 4 screws from bottom of glove box be-
hind top of center bezel. zel (Fig. 5).
(6) Gently pry defroster bezel out of dash pad.
(7) Unplug automatic headlamp and sun sensors
(if equipped) and set defroster grille aside.
(8) Remove 4 screws in defroster duct opening
holding dash pad (Fig. 2).
Fig. 5 Right Side Bezel Attaching Screws
Fig. 2 Upper Dash Pad Attaching Screws

7. ZJ VEHICLE THEFT ALARM 8Q - 7
(13) Remove 4 screws from top of glove box bezel
(Fig. 6).
Fig. 6 Right Side Bezel Upper Screws
(14) Remove 1 screw holding the bezel to the cen- Fig. 8 VTA Module Remove/Install
ter console (Fig. 7).
VTA MODULE RELAY REMOVE/INSTALL
(1) Open glove box and remove 3 screws holding
relay center cover (Fig. 9).
Fig. 9 Relay Center Cover
(2) Remove VTA module relay (Fig. 10).
Fig. 7 Right Side Lower Screw
(15) Remove side window demister boot from glove
box bezel.
(16) Remove right side bezel from instrument
panel.
(17) Unplug glove box light and switch connector.
(18) Remove 2 screws holding VTA module to in-
strument panel (Fig. 8).
(19) Pull module out and unplug connector.
(20) Reverse removal procedures to install. Fig. 10 VTA Module Relay

8. 8Q - 8 VEHICLE THEFT ALARM ZJ
(3) To install, align relay terminals with cavities in (4) Remove screw from bottom of hand hold in
relay center and push relay into place. armrest.
(4) Re-install relay center cover. (5) Remove the trim panel with a wide, flat-bladed
tool (Fig. 12).
HOOD SWITCH REMOVE/INSTALL To aid in removal of the trim panel, start at
(1) Disconnect battery negative cable. the bottom of the panel.
(2) Remove sheet metal screw securing switch to (6) Remove the plastic water shield.
right inner fender (Fig. 11). (7) Remove the U-clip holding the lock cylinder
and disarm switch (Figs. 13 and 14).
Fig. 13 Lock Cylinder Remove
Fig. 11 VTA Hood Switch
(3) Disconnect wire from switch.
(4) Remove switch.
(5) Reverse removal procedures to install.
DOOR DISARM SWITCH REMOVE/INSTALL
(1) Remove screw from demister opening at front
of door.
(2) Remove screw and door handle cover.
(3) Remove screw from under armrest.
Fig. 14 Door Disarm Switch - Typical
Fig. 12 Trim Panel Remove

9. ZJ VEHICLE THEFT ALARM 8Q - 9
(8) Pull the lock cylinder out of the door.
(9) Pry the door disarm switch off the back of the
lock cylinder.
(10) Remove harness clip from door sheet metal.
(11) Unplug the harness connector and remove the
switch.
(12) Reverse removal procedures to install.
LIFTGATE DISARM SWITCH REMOVE/INSTALL
(1) Remove 5 screws holding liftgate interior trim
panel.
(2) Remove the trim panel with a wide, flat-bladed
tool (Fig. 15).
Fig. 16 Liftgate Disarm Switch
(5) Reverse removal procedures to install.
Fig. 15 Liftgate Trim Panel Remove
To aid in removal of the trim panel, start at
the bottom of the panel.
(3) Remove the disarm switch from the liftgate
lock cylinder (Fig. 16).
(4) Unplug the harness connector and remove the
switch.

10. 8Q - 10 VEHICLE THEFT ALARM ZJ
VEHICLE THEFT ALARM SCHEMATIC

11. ZJ VEHICLE THEFT ALARM 8Q - 11
VEHICLE THEFT ALARM SCHEMATIC (CONTINUED)