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 "+" (plus) and bus "-" (minus). 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 MONITOR
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/mini-trip 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/mini-trip 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
The electronic instrument cluster includes a digital speedometer, odometer, oil pressure gauge, coolant temperature gauge, fuel gauge, voltage gauge and a series of warning lights. Electronic instrument cluster 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
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 mechanical instrument cluster over the CCD bus when the ignition switch is in OFF (unlock), RUN and START positions.
All mechanical instrument cluster 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 Overhead Travel Information System (OTIS) provides vehicle operator with supplementary information on a vacuum fluorescent display. 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 vacuum fluorescent display. 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 fuel economy, instant fuel economy, 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
The Vehicle Theft Security System (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).
DRB KEY FUNCTIONS
- YES Or Down Arrow & NO Or Up Arrow
Keys will move lines on screen up or down, allowing technician to choose an item or scroll through all selections available.
- F1 & F2 Keys
Keys are used to scroll through sensor displays.
- ATM Key
Key will return technician to previous screen.
- ENTER Key
Allows technician to select a test or display. The flashing arrow must be on the display user wishes to select. Pressing the ENTER key in the sensor state will cause display to change from a 3-line display to a 1-line display.
- F3 Key
Key is used to display a help screen. This key may be used at any time.
- Number Keys
Keys are used for choosing a display or test by pressing the number for the test or display.
- READ/HOLD Key
Key is used to freeze any sensor display.
- MODE & ATM Keys
Pressing MODE and ATM keys at the same time will cause DRB to reset to copyright screen.
VEHICLES TESTED Mode
At DRB menu, press "1" (VEHICLES TESTED) key. Press ENTER key. At VEHICLES TESTED menu, DRB will display vehicles supported by cartridge used. This screen will display for 5 seconds and return to DRB menu. To return to DRB menu sooner, press ATM key.
HOW TO USE Mode
At DRB menu, press "2" (HOW TO USE) key. Press ENTER key. DRB will display instructions for use of DRB with cartridge being used.
CONFIGURE Mode
At DRB menu, press "3" (CONFIGURE) key. Press ENTER key. At CONFIGURE menu, technician can VIEW or CHANGE DRB display. For example, if metric system is more useful, simply select METRIC from the appropriate menu. All selections made under CONFIGURE option remain active until user changes selection.
SELECT SYSTEM Mode
- This mode enables technician to select system to be diagnosed. At DRB menu, press "4" (SELECT SYSTEM) key. Press ENTER key. DRB will display SELECT SYSTEM menu.
- At SELECT SYSTEM menu, press "3" (BODY) key. Press ENTER key. DRB should display BUS TEST IN PROGRESS, BUS OPERATIONAL. After a moment, SELECT MODULE menu should appear.
- If a bus failure message appears during BUS TEST IN PROGRESS, proceed to VEHICLE COMMUNICATIONS. Always start at TEST 1A.
Menu will display BODY COMPUTER, ELECTRONIC CLUSTER, ELECTRO/MECHANICAL CLUSTER, ENGINE NODE, AUTOMATIC TEMPERATURE CTRL, INFO SYSTEMS (i.e. EVIC, traveler, compass/temperature, compass/mini-trip, or OTIS or BODY SYSTEM TESTS. Select appropriate component/system to be tested. DRB will then display a menu for specific component/system being tested. The following functions can be accessed from each component/system menu
- SYSTEM TESTS
This function allows the technician to determine whether Powertrain Control Module (PCM) is active over the CCD bus.
- READ FAULTS
This functions allows technician to read trouble codes.
- STATE DISPLAY
This functions allows technician to read states or values of a variety of sensors, inputs, outputs and components.
- ACTUATOR TESTS
This function allows technician to activate various outputs, motors and relays to test their operation.
- ADJUSTMENTS
This function allows technician to change Vehicle Theft Security System (VTSS) mode from disarmed to armed or to put VTSS in self-diagnostics mode. Adjustments function is not available for testing of other body control modules.
DRB Volt-Ohmmeter Mode
- To access volt-ohmmeter mode of DRB, connect Red volt-ohmmeter test lead to Red port, located on right top side of DRB. NOTE: Because DRB is grounded through engine diagnostic connector, only one volt-ohmmeter test lead is required when using volt-ohmmeter option. DRB volt-ohmmeter should only be used when self-diagnostics tests require the use of this option.
- To access voltmeter, press VOLT/OHM key once. DRB is now in voltmeter mode. Touch test probe to connector or wire to be measured. Read voltage on DRB display. When voltage testing is complete, press VOLT/OHM key 3 times to exit voltmeter mode.
- To access ohmmeter, press VOLT/OHM key twice. DRB is now in ohmmeter mode. Touch test probe to connector or wire to be measured. Read resistance to circuit ground on DRB display. When resistance testing is complete, press VOLT/OHM key twice to exit ohmmeter mode.
DRB Continuity Meter Mode
Press VOLT/OHM key 3 times. Display will read NO CONTINUITY. Touch test probe to connector or wire to be measured. Read continuity on DRB display. When continuity testing is complete, press VOLT/OHM key once to exit continuity meter mode.
DRB PROBLEMS & ERROR MESSAGES
For DRB problems and/or error messages, proceed to VEHICLE COMMUNICATIONS. Always start at TEST 1A. Testing of NO RESPONSE messages may be found in appropriate BODY CONTROL COMPUTER TESTS.
BODY CONTROL SYSTEM CONNECTORS
Note. For terminal identification of body control system connectors (Scheme 70)- (Scheme 76). 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 WIRING DIAGRAMS.
Scheme 70
Scheme 71
Scheme 72
Scheme 73
Scheme 74
Scheme 75
Scheme 76
VEHICLE COMMUNICATIONS TESTS
Note. Some vehicles may not have specific module/system listed in test. For module/system options available, refer to MODULE APPLICATIONS table under IDENTIFICATION.