CCD BUS SYSTEM
The Chrysler Collision Detection (CCD) bus is a pair of twisted wires traveling from module-to-module receiving and delivering coded information. The code identifies the message and its importance. When multiple messages attempt to access CCD bus at once, code assigns priority ranking.
The 2 twisted wires used by the CCD bus system are called bus "+" (positive) and bus "-" (negative). Both wires carry approximately 2.5 volts. The network consists of some modules with "bias" and some with "termination".
Bias is the part of the voltage divider network which places both bus "+" and bus "-" at 2.5 volts. Termination is the part of the circuitry required to complete the voltage divider network and also provide some electromagnetic protection for the CCD bus. Terminations in all CCD applications have approximately 120 ohms resistance.
COMPASS/TEMPERATURE MODULE
The compass/temperature module is located in overhead console. This dual-function display provides a digital readout of ambient (outside) temperature and 8 primary compass readings to indicate the direction in which vehicle is facing.
The compass/temperature module is self-calibrated and requires no adjustment. The word CAL will be displayed to indicate that the compass is in the fast calibrating mode. The CAL display may be turned off after the vehicle has completed 3 circles without stopping, in an area free of magnetic disturbance.
If the module displays ambient temperature while the compass display is blank, the vehicle must be demagnetized. If compass display still goes blank after the vehicle is demagnetized, the compass/temperature module must be replaced.
ELECTRONIC VEHICLE INFORMATION CENTER (EVIC)
The EVIC module is located in overhead console and displays outside temperature, time, compass direction and fuel economy. The EVIC head monitors information provided by body control module, engine compartment node and powertrain control module. Any failure of a monitored system results in a warning message on EVIC panel display.
ELECTRONIC INSTRUMENT CLUSTER (EIC)
The EIC includes a digital speedometer, odometer, oil pressure gauge, coolant temperature gauge, fuel gauge, voltage gauge and a series of warning lights. EIC receives all of its information for its displays from the body control module and powertrain control module by means of CCD bus system.
ENGINE COMPARTMENT NODE
Engine compartment node is mounted on radiator support. It sends body control module information regarding brake fluid, compass direction (if equipped) engine coolant level and engine oil level.
LIGHT OUTAGE MODULE
Light outage module is located behind glove box. Light outage module monitors exterior lights. If a headlight, side marker light or taillight fails, light outage module senses discrepancy and reports it to body control module.
MECHANICAL INSTRUMENT CLUSTER (MIC)
Body control module sends the angular position of 4 gauges, the status of 7 indicator lights, the status and dimming of PRNDL indicator, the dimming of cruise and low fuel warning lights, and odometer stepper motor information to the MIC over the CCD bus when the ignition switch is in OFF (unlock), RUN and START positions.
All MIC features operate when ignition switch is in the RUN position. The PRNDL feature operates when ignition switch is in the OFF, RUN or START position.
On the transition from OFF to RUN position, a bulb check is performed. This bulb check consists of activating all CCD controlled indicator lights and all PRNDL segments for approximately 2-4 seconds. PRNDL bulb check is aborted if gear selector is moved out of Park position and if tachometer exceeds 450 RPM.
OVERHEAD TRAVEL INFORMATION SYSTEM (OTIS)
The OTIS provides vehicle operator with supplementary information on a Vacuum Fluorescent Display (VFD). The OTIS is located in overhead console. Vehicle operator selects and resets display functions through the use of 4 buttons (US/M, STEP, C/T and RESET). The OTIS obtains most of the information from the CCD bus.
The OTIS powers up when it senses vehicle (battery) voltage on the ignition input circuit. The OTIS blanks the display, then illuminates all segments of the VFD. During this time, the OTIS sends and receives information over CCD bus to determine what to display after its 2 second initialization. The OTIS displays dashes (- -) for any of the screens for which it did not receive bus messages during the 2 second initialization. Dashes will be replaced by valid information if and when it is received.
TRAVELER MODULE
Traveler module is located on dashboard, just right of steering column. It provides vehicle operator with navigational information such as Average (AVE) fuel economy, instant fuel Economy (ECHO), Distance To Empty (DTE), Estimated Time (ET) and trip odometer (ODO). Traveler module receives fuel and odometer information from body control module and powertrain control module via the CCD bus system.
VEHICLE THEFT SECURITY SYSTEM (VTSS)
The VTSS module is located behind glove box. VTSS monitors vehicle doors, hood, trunk key cylinder and ignition for unauthorized operation/entry. When alarm is triggered, the horn will sound for 3 minutes and the parking lights will flash for 15-18 minutes.
When an unauthorized entry into vehicle occurs, the VTSS module signals Powertrain Control Module (PCM) via CCD bus that it is not okay to start the engine. The PCM then "zeros out" the pulse width of the fuel injectors, thus preventing the engine from starting (start/stall condition). The engine will NOT start until VTSS is disarmed.
Initialization & Verification
An initialization procedure, included in VTSS, requires that vehicle record 20 engine cranking cycles before allowing VTSS module to function. For this reason, VTSS requires verification. To verify VTSS, perform the following: Open driver's door (all others closed). Remove ignition key. Lock doors with power door lock switch. Close driver's door. If VTSS SET light flashes, system is armed and operational. If VTSS SET light does not flash, 20 engine cranking cycles have not occurred or there is a problem with VTSS.
Manual Override Mode & Tamper Alert Mode
The VTSS will not arm if the doors are locked using the key or the manual lock control (manual override mode). If horn sounds 3 times when either front door is unlocked, the alarm was activated/triggered (tamper alert mode).
Self-Diagnostic Mode
VTSS self-diagnostic mode verifies operation of all monitored switches/circuits. There are NO codes for the VTSS, only symptoms. VTSS self-diagnostic mode can be entered only with scan tool.
Upon entering self-diagnostic mode, horn should sound at each of the following events, to indicate proper operation.
- Beginning with doors closed, open then close each door. The horn should sound when door ajar switch closes and then again when switch opens. Wait one second when opening/closing door ajar switch (door).
- Open and close hood. The horn should sound when hood is opened then closed. Actuate power door locks in both the lock and unlock direction. The horn should sound after each actuation.
- Using key, rotate each door lock cylinder to unlock position. The horn should sound when switch closes and then again when switch opens. Wait one second when opening/closing switch, or the horn will not sound.
- Turn ignition switch to RUN position. Horn should sound once to indicate proper operation of ignition (switch) input. This step will also take VTSS module out of self-diagnostic mode.
BODY CONTROL COMPUTER TESTS DIRECTORY
Use tests listed in BODY CONTROL COMPUTER TESTS DIRECTORY table when using scan tool.
| Application | Page |
|---|---|
| Body Control Computer Tests (1) | 1-285 |
| Vehicle Communications (2) | 1-314 |
| (1) Acclaim, Avenger, Neon, Sebring, Spirit and Talon models are not equipped with a body control module. For testing, scan tool problems and/or error messages, proceed to BODY CONTROL COMPUTER. (2) Vehicle communications tests should only be used when instructed to do so by another test. | |
| (1) | Acclaim, Avenger, Neon, Sebring, Spirit and Talon models are not equipped with a body control module. For testing, scan tool problems and/or error messages, proceed to BODY CONTROL COMPUTER. |
| (2) | Vehicle communications tests should only be used when instructed to do so by another test. |
BODY CONTROL COMPUTER TESTS DIRECTORY
CLEARING DTCS
| CAUTION | When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery. |
DTCs can be cleared by disconnecting negative battery cable for at least 15 seconds, allowing computer system to clear DTCs. DTCs can also be cleared using scan tool. See step 4) under SELF-DIAGNOSTIC SYSTEM .
BODY CONTROL SYSTEM CONNECTORS
Note. For terminal identification of body control system connectors (Scheme 24)-7. Connector terminal numbers are molded into connectors. If connector terminal identification differs from that shown in figure, use wire colors to ensure correct circuit is being tested. For wiring diagrams, see appropriate article in ENGINE PERFORMANCE
- «WIRING DIAGRAMS - 3.3L»(ref-11016)
- «WIRING DIAGRAMS - 3.5L»(ref-11019)
Scheme 24
Scheme 25
Scheme 26
Scheme 27
Scheme 28
Scheme 29
VEHICLE COMMUNICATIONS TESTS
Note. Some vehicles may not have specific module/system listed in test. For module/system options refer to MODULE APPLICATIONS table.