VEHICLE THEFT ALARM

CONTENTS

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DIAGNOSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1

SERVICE PROCEDURES . . . . . . . . . . . . . . . . . . . 6

GENERAL INFORMATION

The Vehicle Theft Alarm (VTA) system is an avail-able option on Grand Cherokee models. This systemis designed to protect against vehicle theft by moni-toring vehicle doors, hood, liftgate and ignition actionfor unauthorized operation. When unauthorized oper-ation is detected, the VTA system responds by sound-ing the horn, flashing the headlamps, park and taillamps and providing an engine no-run feature. Fol-lowing are general descriptions of the features of theVTA system. Refer to Group 8W - Wiring Diagramsfor complete circuit descriptions and diagrams.

ARMINGPassive arming occurs upon normal vehicle exit (ig-

nition OFF, open door, lock with power lock switch,close door). The alarm system will not arm if thedoors are manually locked, providing a manual over-ride of alarm.

Active arming occurs when the remote keyless en-try transmitter is used to lock the vehicle doors,whether the doors are open or closed. If one or moredoors are open, the arming sequence is completedonly after all doors and the liftgate are closed.

After active or passive arming, the security lamp inthe instrument panel will flash for 15 seconds, show-ing that arming is in progress. Note that this 15 sec-ond arming period will start after the illuminatedentry system has timed out (courtesy lamps off). If nomonitored systems are activated during this period,the system will arm.

If the hood switch is not seen by the system, thesecurity lamp will remain steadily lit during thearming process. While the system will still arm, theengine compartment will not be protected from entrywhen the security lamp remains steadily lit duringthe arming process.

DISARMINGPassive disarming occurs upon normal vehicle en-

try (unlocking either front door or liftgate, with thekey). This disarming also will halt the alarm, once ithas been activated.

Active disarming occurs when the remote keylessentry transmitter is used to unlock the vehicle doors.This disarming also will halt the alarm, once it hasbeen activated.

POWER-UP MODEWhen the battery is disconnected and then recon-

nected, or when the battery has been drained andthe vehicle is being jump started, the VTA system en-ters its power-up alarm mode which:• flashes the headlamps• flashes the park and tail lamps• prevents the engine from running.

The alarm system must be actively or pas-sively disarmed to exit the power-up mode afterany battery reconnection.

TAMPER ALERTA tamper alert feature notifies the driver that the

alarm had been activated, and has since timed-out(alarmed for more than 18 minutes). This alert gives3 horn pulses when the system is actively or pas-sively disarmed.

ON-BOARD DIAGNOSTIC SYSTEMThe DRB scan tool may be used to test the VTA

system. Refer to the appropriate Diagnostic Proce-dures manual for more information.

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DIAGNOSIS

SELF-DIAGNOSISA self-diagnosis mode is available in the VTA sys-

tem to verify operation of all monitored switches orcircuits. To enter this mode, cycle the ignition switchACCESSORY-OFF-ACCESSORY-OFF-ACCESSORY,leaving the switch in the ACCESSORY position.

Upon entering the self-diagnosis mode the head-lamps, park and tail lamps will begin flashing to ver-ify their operation. In addition, the horn will soundtwice. Returning the ignition to the OFF position willstop the lamps from flashing while keeping the sys-tem in the diagnostic mode.

Also note that vehicles equipped with VTA areequipped with the illuminated entry system. When inthe diagnostic mode it is recommended that the illu-minated entry relay be removed. Otherwise, it is nec-essary to wait 30 second for the illuminated entrysystem to time out after each door opening or clo-sure.

While in the diagnostic mode, a horn pulse shouldoccur at each of the following events indicatingproper operation. However, if a switch is cycled tooquickly and does not remain open or closed for atleast 1 second, the horn will not sound to confirm op-eration.

(1) Beginning with all doors closed, open then closeeach door. The horn will sound when the door jambswitch closes, and again when the switch opens.There must be a 1 second delay between closing andopening the switch.

(2) Open, then close the hood. The horn will soundwhen the hood is opened, and again when it is closed.

(3) Activate the power door locks in both the lockand unlock directions. The horn will sound after eachactivation.

(4) Rotate the key in each door lock cylinder to thelock position, then to the unlock position. The hornwill sound as the switch closes, and again when itopens. There must be a 1 second delay betweenchanging switch states, or the horn will not sound.

(5) Activate the remote keyless entry in both thelock and unlock directions. The horn will sound aftereach activation.

(6) Cycle the ignition key to the ignition switch ONposition. A single horn pulse will indicate proper op-eration of the ignition input. This also will take themodule out of the diagnostic mode.

The lack of a horn pulse response to any of theabove tests indicates:• a switch failure• an open or shorted circuit between the switch andthe VTA module• an internal VTA module failure.

Check for continuity at the switch. If OK, check foran open or shorted wire between the switch and VTAmodule. Also, check if the powertrain control module(PCM) has been replaced recently. For the first 20engine starts with a new PCM, the VTA will functionnormally except for the engine no-run feature.

A PCM from a vehicle equipped with VTA can-not be used in a vehicle that is not equippedwith VTA.

If the security lamp comes on after ignitionON and stays on, the CCD bus communicationwith the PCM has been lost.

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VEHICLE THEFT ALARM DIAGNOSIS

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VEHICLE THEFT ALARM DIAGNOSIS (CONTINUED)

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VEHICLE THEFT ALARM DIAGNOSIS (CONTINUED)

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SERVICE PROCEDURES

VTA MODULE REMOVE/INSTALL(1) Disconnect battery negative cable.(2) Remove ash receiver.(3) Remove 6 screws holding center cluster bezel

(Fig. 1).

(4) Remove center bezel.(5) Remove 2 screws holding dash pad located be-

hind top of center bezel.(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).

(9) Remove 3 screws above instrument panel clus-ter holding dash pad (Fig. 3).

(10) Open glove box and remove 2 screws holdingdash pad (Fig. 4).

(11) Remove dash pad prying gently on each end tounsnap end clips.

(12) Remove 4 screws from bottom of glove box be-zel (Fig. 5).

Fig. 2 Upper Dash Pad Attaching Screws

Fig. 1 Remove Center Bezel Retaining Screws

Fig. 3 Remove Screws Holding Dash Pad

Fig. 4 Remove Screws Holding Dash Pad

Fig. 5 Right Side Bezel Attaching Screws

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(13) Remove 4 screws from top of glove box bezel(Fig. 6).

(14) Remove 1 screw holding the bezel to the cen-ter console (Fig. 7).

(15) Remove side window demister boot from glovebox bezel.

(16) Remove right side bezel from instrumentpanel.

(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.

VTA MODULE RELAY REMOVE/INSTALL(1) Open glove box and remove 3 screws holding

relay center cover (Fig. 9).

(2) Remove VTA module relay (Fig. 10).

Fig. 6 Right Side Bezel Upper Screws

Fig. 7 Right Side Lower Screw

Fig. 8 VTA Module Remove/Install

Fig. 9 Relay Center Cover

Fig. 10 VTA Module Relay

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(3) To install, align relay terminals with cavities inrelay center and push relay into place.

(4) Re-install relay center cover.

HOOD SWITCH REMOVE/INSTALL(1) Disconnect battery negative cable.(2) Remove sheet metal screw securing switch to

right inner fender (Fig. 11).

(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.

(4) Remove screw from bottom of hand hold inarmrest.

(5) Remove the trim panel with a wide, flat-bladedtool (Fig. 12).

To aid in removal of the trim panel, start atthe bottom of the panel.

(6) Remove the plastic water shield.(7) Remove the U-clip holding the lock cylinder

and disarm switch (Figs. 13 and 14).

Fig. 12 Trim Panel Remove

Fig. 11 VTA Hood Switch

Fig. 13 Lock Cylinder Remove

Fig. 14 Door Disarm Switch - Typical

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(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).

To aid in removal of the trim panel, start atthe bottom of the panel.

(3) Remove the disarm switch from the liftgatelock cylinder (Fig. 16).

(4) Unplug the harness connector and remove theswitch.

(5) Reverse removal procedures to install.

Fig. 15 Liftgate Trim Panel Remove

Fig. 16 Liftgate Disarm Switch

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VEHICLE THEFT ALARM SCHEMATIC

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VEHICLE THEFT ALARM SCHEMATIC (CONTINUED)

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