to sink this current and pull the bus to ground on the falling edge of the symbols. The bus
resistance is minimum of 315 ohms to a maximum of 2 K ohms. The termination capacitance is
required for noise filtering and to help in the symbol wave shaping. The bus capacitance shall not
be greater then 12,000 pf.
Each module on the PCI bus has a small termination load of a parallel resistance and capacitor
to make up part of the over all bus termination load. One or two modules on the PCI bus may have
a higher load termination to provide stabilizing influence over the variations of vehicle builds.
These modules, called dominant modules, may very from car line to car line. The Powertrain
Control Module (PCM) is the only dominant node for this vehicle.
NOTE: Communication over the bus is essential to the proper operation of the vehicles on-board
diagnostic systems and the DRB. Problems with the operation of the bus or DRB must be
corrected before proceeding with diagnostic testing. If there is a problem, refer to the Vehicle
Communications section of this manual.
3.14.1
Bus Failure Message
Odometer Displays
9
No Bus
9
- The Mechanical Instrument Cluster (MIC) cannot communicate
over the bus and does not know why.
3.15
Vehicle Theft Security System
This passive system is designed to protect against vehicle theft. The vehicle theft security system
(VTSS) is part of the body control module, which monitors vehicle doors and the ignition for
unauthorized operation. The alarm activates by sounding the horn, flashing the headlamps, park
and tail lamps, and the VTSS indicator lamp. Passive arming occurs upon normal vehicle exit by
turning the ignition off, opening the driver’s door, locking the doors with the power lock, and
closing the driver’s door or locking the doors with RKE. Manual arming occurs by using the key
to lock the doors after closing them. The indicator lamp on the dash will flash for 15 seconds,
showing that arming is in progress. If no monitored systems are activated during this period, the
system will arm and the indicator will flash at a slow rate. If the indicator lamp remains steadily lit
during the arming process, this can indicate a possible loss of communication with the PCM or
loss of trunk knock out switch. When something triggers the alarm, the system will signal the
headlamps, park lamps, and horn for about 3 minutes.
For complaints about the Theft Alarm going off on it’s own use the DRB and select
9
Theft Alarm
9
then
9
Monitor Display
9
and read the
9
Alarm Tripped By
9
status.
Tamper Alert - The VTSS indicator lamp will flash twice quickly to indicate a tamper condition has
occurred.
Manual Override - The system will not arm if the doors are locked using the manual lock control
(by hand) or if the locks are actuated by an inside occupant after the door is closed.
To verify the system, proceed as follows:
1. Open the driver’s door.
2. Remove the ignition key (but keep it in hand).
3. Lock the doors with the power lock switch or the RKE.
4. Close the driver’s door.
NOTE: After the doors are closed, locking the doors with RKE will also arm the system.
NOTE: If the VTSS indicator lamp flashed, the system is operational and verified. If not, there may
be a problem with the system.
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