Operating Modes

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

Following are paragraphs that briefly describe the operation of each of the VTA operating modes.

Enabling - The BCM and the RFHM must have the VTA function electronically enabled in order for the VTA to perform as designed. The BCM stores and compares vehicle configuration data with other Electronic Control Units (ECU) in the vehicle, including the RFHM. This process is referred to as PRogramming Of Configuration of Systems Integrated (PROCSI) (also known as PROXI). If a configuration mismatch is detected, the BCM sets a Diagnostic Trouble Code (DTC). A configuration mismatch will require the performance of a Restore BCM PROXI Configuration routine, or a PROXI Configuration Alignment routine using a diagnostic scan tool.
Arming - Passive arming of the VTA occurs when the vehicle is exited with the key or Frequency Operated Button with Integrated Key (FOBIK) removed from the ignition, the headlamps are turned Off and the doors are locked while they are open using the power lock switch. Active arming occurs when the Lock button on the Remote Keyless Entry (RKE) transmitter is depressed to lock the vehicle. For active arming to occur, the doors and the liftgate must be closed and the status of the ignition must be Off when the RKE transmitter Lock button is depressed. The power lock switch will not function if a key or FOBIK is in the ignition with the driver side front door open.
Pre-arming of the VTA is initiated when the vehicle is locked using a power door lock switch or when the RKE transmitter Lock button is depressed. Pre-arming will not occur if the key or FOBIK is in the ignition with the driver side front door open. When the VTA is pre-armed, the arming sequence is delayed until all of the doors and the liftgate have been closed. The VTA will remain in pre-armed mode for up to 16 seconds after all doors and the liftgate have been closed.

Once the VTA begins the passive or active arming sequence, the security indicator in the Instrument Panel Cluster (IPC) will flash rapidly for about 16 seconds. This indicates that VTA arming is in progress. If the ignition status transitions to On, if a door or the liftgate is unlocked or opened by any means, or if the RKE Panic button (if equipped) is depressed during the 16 second arming process, the security indicator will stop flashing and the arming process will abort. Once the arming sequence is successfully completed, the security indicator will flash at a slower rate, indicating that the VTA is armed.

On vehicles equipped with the hood ajar switch, the VTA arming sequence will occur regardless of whether the hood is open or closed, but the security indicator will illuminate solid and the engine compartment will not be protected unless the hood is closed when the VTA arming sequence first begins. Also, if the status of the hood ajar switch changes from open to closed during the 16 second arming process, the security indicator will switch from solid to flashing. Once the arming process is successfully completed, the security indicator will flash at a slower rate, indicating that the VTA is armed.
Disarming - Passive disarming of the VTA occurs by inserting a valid Sentry Key Immobilizer System (SKIS) key or FOBIK into the ignition or when the ignition status transitions to On. Active disarming of the VTA for all markets occurs when the vehicle is unlocked by depressing the Unlock button of the RKE transmitter. Once the alarm has been activated, either disarming method will also deactivate the alarm. Depressing the Panic button (if equipped) on the RKE transmitter will not disarm the VTA.
Alarm - The VTA alarm output provides both visual and audible outputs; however, the time intervals of these outputs vary by the requirements of the market for which the vehicle is manufactured. In all cases, the visual output will be a flashing On and Off of the exterior lamps, while the audible output will be either a pulsing of the horn or, if the vehicle is so equipped, the siren. For vehicles with the base version of the VTA, the inputs that will trigger the alarm include a change in the status of the ignition, the door ajar switches, the liftgate ajar switch and, in vehicles built for certain markets where they are required, the hood ajar switch. In vehicles with the premium version of the VTA, the inputs that will trigger the alarm also include any movement detected within the vehicle passenger compartment, or a change in the vehicle pitch or roll of greater than about 0.5 degrees.
Power-Up Mode - When the armed VTA senses that the battery has been disconnected and reconnected, it enters its power-up mode. In the power-up mode the armed alarm system remains armed following a battery failure or disconnect. If the VTA was armed prior to a battery disconnect or failure, the technician or vehicle operator will have to actively or passively disarm the alarm system after the battery is reconnected. The power-up mode will also apply if the battery goes dead while the system is armed, and battery jump-starting is attempted. The VTA will be armed until the technician or vehicle operator has actively or passively disarmed the alarm system.
If the VTA is in the disarmed mode prior to a battery disconnect or failure, it will remain disarmed after the battery is reconnected or replaced, or if jump-starting is attempted.
Tamper Alert - The VTA tamper alert feature will pulse the horn three times upon VTA disarming if the alarm was triggered and has since timed out, or if the battery has been disconnected and reconnected. This feature alerts the vehicle operator that the VTA alarm was activated while the vehicle was unattended. This feature is disabled in vehicles manufactured for certain export markets where it is required.
Antitilt And Intrusion Alarm Disabling - The antitilt and intrusion alarm is an exclusive feature of the premium version of the VTA. When this version of the VTA is armed, the Ultrasonic and Antitilt Module (UAM) uses ultrasonic transmit and receive transducers to monitor the interior of the vehicle for movement and low gravity accelerometers to monitor vehicle pitch and roll. If interior motion or change in vehicle attitude are detected, the UAM sends an electronic message to the BCM over the Local Interface Network (LIN) data bus to invoke the audible and visual alarm features.
The antitilt and intrusion alarm features of the premium VTA can be disabled by depressing the Lock button on the RKE transmitter 3 times within 15 seconds during VTA pre-arming, while the security indicator is still flashing rapidly. The VTA provides a single short siren chirp as an audible confirmation that the antitilt and intrusion alarm features disable request has been received. The default for the UAM features is enabled; therefore, the disable procedure must be repeated each time the VTA is disarmed, then armed again to prevent the system from monitoring interior movement and vehicle pitch and roll.