Vision V6-215 3.5L SOHC (1995)
The lack of a horn pulse during any operation indicates either:
-
A switch failure
-
The lack of that input to the module a failure internal to the module
-
A faulty horn system
Check for continuity at the switch. If this is good, check for an open or shorted wire between the switch and body control module. Also, check if
the powertrain control module (PCM) has been replaced recently.
NOTE: A powertrain control module from a vehicle equipped with a vehicle theft security system cannot be used in a vehicle that is not equipped
with a vehicle theft security system.
If the VTSS indicator lamp comes on after ignition ON and stays on, the CCD bus communication with the powertrain control module possible has
been lost.
Diagnostic trouble codes - There are no diagnostic trouble codes for the vehicle theft security system, only symptoms.
Vehicle Communication
The body system consists of a combination of modules that communicate over the CCD (Chrysler Collision Detection multiplex system) bus.
Through the CCD bus, information about the operation of vehicle components and circuits is relayed to the appropriate module(s). Each module
receives the same information about a component or circuit as the other modules do. This significantly reduces the complexity of the wiring in the
vehicle and the size of the wiring harnesses.
The Chrysler Collision Detection multiplex system (CCD bus) consists of a twisted pair of wires. These wires run from one module to another.
They receive and deliver coded information between the modules. The information is coded to identify the message as well as the importance of
the message. When there are multiple messages trying to access the CCD bus at one time, the code determines the message that has higher priority,
which is then allowed to access the bus first.
The two wires (D1) and (D2) of the twisted pair that make up the CCD multiplex system are called "bus +" (bus plus) and "bus -" (bus minus)
respectively. Each wire has a measurable voltage level of roughly 2.5 volts. In order to maintain the 2.5 volts on each line and provide a means of
transportation for the coded messages, there is a "voltage divider network." This network consists of some modules with bias and some with
termination. Bias is the part of the voltage divider network that places both bus+ and bus- at 2.5 volts. Termination in the circuitry is required to
complete the voltage divider network and also to provide some electromagnetic protection for the bus.
NOTE: Communication over the bus is essential to the proper operation of the vehicle's on-board diagnostic systems and the DRB (scan tool).
Problems with the operation of the bus or DRB (scan tool) must be corrected before proceeding with diagnostic testing. If there is a problem, refer
to the Vehicle Communications Diagnostic Charts for diagnostis and repair procedures.
Any of the following bus failure messages may be displayed:
-
Short to Battery - Either or both of the bus wires are shorted to the battery potential.
-
Short to 5 Volts - Either or both of the bus wires are shorted to a 5-volt potential.
-
Short to Ground - Either or both of the bus wires are shorted to ground or ground wire at DLC is open.
-
Bus (+) & Bus (-) Shorted Together - The two bus wires are shorted together.
-
No Termination - The bus system has lost connection with all of its terminators.
-
Bus Bias Level Too Low - Either or both of the bus wire potentials are significantly below their normal 2.5 volts.
-
Bus Bias Level Too High - Either or both of the bus wire potentials are significantly above their normal 2.5 volts.
-
No Bus Bias - The bus system has lost connection with all modules that provide bias.
-
Bus (+) Open - The bus (+) wire has lost connection with termination and/or bias.
-
Bus (-) Open - The bus (-) wire has lost connection with termination and/or bias.
-
Not Receiving Bus Messages Correctly - The DRB cannot communicate over the bus and does not know why.
Wiper System
The wiper system provides the driver with normal wipe (low and high speeds), intermittent wiper, wipe after wash, and pulse wipe functions. The
driver selects the wiper function via a resistive multiplexed stalk switch mounted on the steering column. This value is then received by the BCM,
which then determines the wiper motor output speed and frequency.
Pulse Wipe - When the wiper is in the off position and the driver presses the wash button for more than 62 msec but less than 1/2 second, 1 wipe
cycle in low speed mode will be provided.
Wipe After Wash Mode - When the driver presses the wash button for over 1/2 second and then releases it, the wiper will continue to run for 2
additional wipe cycles.
