Part 4 of 5
INSTRUMENT CLUSTERThe Instrument Cluster receives and sends messages to other modules via the PCI bus circuit. The indicator lamps will illuminate briefly for a bulb check when the ignition is turned from OFF to run. All of the gauges receive their information via the PCI bus from the powertrain control module and body control module.
The gauges and the LEDs are not individually replaceable thereby requiring complete replacement of the Instrument Cluster if a repair is necessary. In the event that the Instrument Cluster looses communication with other modules on the PCI bus, the cluster will display no bus in the VF display.
The Trip/Reset button is used to switch the display from trip to total mileage. Holding the button when the display is in the trip mode will reset the trip mileage. This button is also used to put the cluster in self-diagnostic mode. The odometer display uses blue-green vacuum fluorescent digital characters.
On base Voyager and Caravan SE with the 2.4- liter engine and three-speed transaxle, the Instrument Cluster has three gauges: Speedometer, fuel and temperature. A red dot that moves transversely appears through openings in the Instrument Cluster face (P-R-N-D-2-1) to indicate the gear selected.
With all other models, the Instrument Cluster also includes a tachometer and uses a vacuum-fluorescent shift indicator.
The Town & Country Instrument Cluster features Electroluminescent Illumination of the gauge faces (EL Panel). This feature eliminates the use of bulbs for gauge/panel lighting. In a manor similar to fluorescent lights, a/c voltage from an inverter integrated circuit chip is applied to the phosphorescent material, causing it to glow. The phosphorescent material is screen-printed onto flexible Mylar sheets that form the gauge faces.
The odometer display and door/liftgate ajar indicators turn ON when a door is opened to assist both the customer and service technician to view the odometer without turning the ignition ON.
On Grand Caravan ES with AutoStick, the display includes an O/D OFF indicator that is illuminated when the driver presses the overdrive off button on the transaxle shifter.
Instrument Cluster Self Test
1. Depress and hold the Odometer Reset button.
2. Turn the ignition switch to ON.
3. Release the Odometer reset button.
The Instrument Cluster will illuminate all indicators and step the gauges through several calibration points. Also, the odometer will display any stored codes that may have set.
Message Center
The Message Center above the brow of the Instrument Cluster is on Caravan Sport, Caravan ES, Voyager LX and all Town & Country models. It houses the following warning indicators: Check Engine/Service Engine Soon, high beam, left and right turn signals, Security Alarm Set, and low oil pressure. On base Voyager and Caravan SE models equipped with the three-speed transaxle, these indicators appear in the face of the cluster. The Security Alarm set indicator is now a large red circle an ISO symbol.
Activation of Instrument Cluster indicators is coordinated with indicators in the message center and EVIC, where used, to avoid redundancy. A revised safety standard now requires that the seat belt warning lamp in the Instrument Cluster remain lit if the driver seat belt is not buckled. A headlamp out ISO indicator has been added to the Instrument Cluster to alert the driver when a headlamp is not functioning.
INTERIOR LIGHTING
Courtesy Lamp Control
The body controller has direct control over all of the vehicle's courtesy lamps. The body computer will illuminate the courtesy lamps under any of the following conditions:
1. Any door ajar and courtesy lamp switch on the headlamp switch is not in the dome off position.
2. The courtesy lamp switch on the headlamp switch is in the dome on position.
3. A Remote Keyless entry unlock message is received.
4. Driver door unlocked with key (with VTSS only)
Illuminated Entry
Illuminated entry will be initiated when the customer enters the vehicle by unlocking the doors with the key fob, or with the key if the vehicle is equipped with vehicle theft alarm. Upon exiting the vehicle, if the lock button is pressed with a door open, illuminated entry will cancel when the door closes. If the doors are closed and the ignition switch is turned ON, the illuminated entry also cancels. The illuminated entry feature will not operate if the courtesy lamp switch is in the dome OFF position.
Interior Lighting Battery Saver
If any of the interior lamps are left ON after the ignition is turned OFF, the BCM will turn them OFF after 8 minutes. To return to normal operation, the courtesy lamps will operate after the dome lamp switch or door ajar switch changes state. The glove box and switched reading lamps require that the ignition be turned to the ON/acc position.
MEMORY SYSTEM
The memory system consists of power driver's seat, power mirrors and radio presets. The Memory Seat/Mirror Module (MSMM) is located under the driver's seat. It receives input from the following: driver's manual 8-way seat switch, driver's seat position sensors, PCI bus circuits, and the power mirror sensors. The module uses these inputs to perform the following functions: position the driver's memory seat, both exterior mirrors (during recalls), and send/receive the memory system information over the PCI bus.
The Memory Set Switch is wired to the Body Control Module (BCM). When a button (either #1 or #2) is pressed on the set switch causes the to BCM send a message to the MSMM which in turn sends a motion status messages to the BCM. If the BCM receives no motion from the MSMM it will send a recall message to the MSMM and radio (once ignition is in run or accessory). The MSMM will in turn position the drivers seat, both mirrors along with recalling the radio presets. If the drivers seat or either exterior mirror is inoperative from its own respective switches, use the service information and schematic to diagnose the problem. This manual addresses the memory problems only and it is assumed there is not a basic component failure.
Power Seat
The memory power seat provides the driver with 2 position settings for the driver's seat. Each power seat motor is connected to the MSMM with two motor drive circuits. Each circuit is switched between battery and ground. By being able to bi-directionally drive the circuits, the MSMM controls the movement of the motors based on input from the power seat switch or from the position sensors when performing a memory recall. Each motor contains a potentiometer to monitor the seat position. To monitor the position of the motor, the MSMM sends out a 5-volt reference on the sensor supply circuit. The sensor is grounded back to the module on a common ground circuit. Based on the position of the sensor, the MSMM monitors the voltage change through the sensor on a separate signal circuit.
The MSMM stores the input value of each of the four seat potentiometers in memory when the system requests a set. The driver can initiate a memory recall, using either the door mounted memory switch or the RKE transmitter (if the remote linked to memory feature is enabled via the EVIC). When initiated, the MSMM adjusts the four seat sensors (by using the motors) to match the memorized seat position data.
For safety, the memory seat recall is disabled by the MSMM when the vehicle is out of park position or if the speed is not zero. Any obstruction to seat movement over a 2-second delay will cause the seat to stop moving in which case a stalled motor would be detected by the MSMM and the corresponding seat output would be deactivated. However, if the object obstructing the seat is removed, the seat will function normally again.
Memory Mirrors
Each outside mirror contains vertical and horizontal bi-directional drive positioning motors and position sensors. The MSMM provides a 5-volt reference on the signal circuit to each position sensor. The sensors share a common ground circuit. The MSMM monitors the position of the mirror motors by measuring the voltage on each signal circuit. When a memory position is set, the MSMM monitors and stores the position of the outside mirrors. The MSMM adjusts the mirrors to the appropriate positions when a memory recall message is received from the RKE or is requested from the memory set switch.
The power mirror switch during non-memory operation operates both mirrors independently of the MSMM.
OVERHEAD CONSOLE
Compass/mini-trip Computer (CMTC)
The compass/mini-trip computer is located in the overhead console. It displays to the driver the direction the vehicle is traveling and the current outside temperature, as well as the following traveler navigational information: average fuel economy (AVG ECO), distance to empty (DTE), instantaneous fuel economy (ECO), elapsed time (ET), and trip odometer (ODO). The information needed for the CMTC functions is received over the PCI bus from other modules.
Electronic Vehicle Information Center (EVIC)
The Electronic Vehicle Information Center (EVIC) includes all the same function and is located in the same area as the Compass/Mini-Trip Computer, but it adds a number of warning messages. Also, the trip computer messages are spelled out on the screen, for example, DISTANCE TO EMPTY where the Mini-Trip Computer displays only shows DTE.
If the compass/mini-trip computer or EVIC has been replaced, it may be necessary to reset the calibration.
Setting The Compass
The compass/mini-trip module and EVIC are self-calibrated and requires no adjustment. The word CAL will be displayed to indicate that the compass is in the fast calibrating mode. CAL will turn off after the vehicle has gone in three complete circles without stopping, in an area free of magnetic disturbance.
If the module displays the temperature while the compass is blank or shows a false reading, the vehicle must be demagnetized.
If the compass still goes blank after the vehicle is demagnetized, the compass/mini-trip/EVIC module must be replaced.
Setting The Variance
Variance is the difference between magnetic north and geographic north. To determine the variance for the area you are in, refer to the following zone map provided. The number shown for your area is the variance number for your area.
1. Set the compass/mini-trip console (CMTC) to compass/temperature mode.
2. Press and hold down the RESET button for 5 seconds. NOTE: If the button is held for 10 seconds instead of 5, the CMTC will set the variance to 8 and enter the fast calibration mode.
3. The VAR light will come ON and the last variance setting will be displayed.
4. Press the STEP button to set the zone number.
5. Press the US/M button and resume normal operation.
NOTE: DO NOT ATTACH ANY MAGNETIC DEVICE SUCH AS A MAGNETIC CB ANTENNA TO THE VEHICLE. THIS CAN CAUSE THE COMPASS TO GIVE FALSE READINGS.
POWER DOOR LOCK SYSTEM
When the BCM receives input for a lock request from a door lock switch, RKE or cylinder lock switch (only with VTSS), it will turn the lock driver on for a specified time of 375 msec. If the request is there beyond 375 msec, the BCM considers the door lock signal stuck. Once a door lock or unlock signal is stuck for longer than 10 seconds, the BCM will set a trouble code and the signal input is ignored until the stuck condition disappears. The door lock switches provide a variable amount of resistance thereby dropping the voltage of the multiplexed (MUX) circuit and the BCM will respond to that command.
Sliding Door Memory Lock
When the BCM receives an input for a lock request and a sliding door is open, the BCM will turn ON the lock driver as described above, and will turn it ON again when all sliding doors are closed. NOTE: If the BCM receives an unlock input before a sliding door is closed, this will cancel the memory lock.
Door Lock Inhibit
When the key is in the ignition and in any position and either front door is open, the door lock switches LOCK functions are disabled. The UNLOCK functions are still functional. This protects against locking the vehicle with the keys still in the ignition. The RKE key fob will still lock the doors as usual. This allows the driver to lock the vehicle with the engine running for warm up.
Automatic Door Locks
This feature can be enabled or disabled by using either the DRBIII(R) or the customer programming method. When enabled all the doors will lock when the vehicle reaches a speed of 18 MPH (29 KMH) and all the doors are closed. If a door is opened and the vehicle slows to below 18 MPH (29 KMH), the door locks will operate again once all doors are closed and the speed is above 15 MPH (24 KMH).
Remote Keyless Entry (RKE)
The body control module interfaces with the RKE module via a one-way serial bus interface. The RKE module is not on the PCI bus. The RKE module sends a 0 - 5 volt pulse width signal to the BCM depending on which button on the transmitter was pressed. The BCM controls the door lock/unlock functions and the arming/disarming of the Vehicle Theft Security System (if equipped) and the activation of illuminated entry. The BCM will also send the appropriate messages to the Power Sliding Doors and Power Liftgate modules. The Intelligent Power Module (IPM) activates the park lamps, headlamps, and horn for horn chirp when sent the appropriate message from the BCM as received from the RKE transmitter. When a one-button press is made for unlock, both driver side doors will unlock and the front and rear turn signal will flash. When a second press is initiated (within 5 seconds of the first) both passenger doors will unlock and all four turn signals will flash.
The RKE module is capable of retaining up to 4 individual access codes (4 transmitters). If the PRNDL is in any position except park, the BCM will ground the interface thereby disabling the RKE.
Both the 3 and 6 buttons transmitters will have 2-CR2016 batteries in series. The minimum battery life should be approximately 4.7 years based on 20 transmissions a day at 84 °F (25 °C). Using the DRBIII(R) and selecting RKE FOB Test can test the transmitter.
The RKE module can be programmed via the DRBIII(R) or the customer programming method. The BCM will only allow programming mode to be entered when the ignition is in the on position, the PRNDL is in park position, and the VTSS (if equipped) is in the disarmed mode.
POWER LIFTGATE SYSTEM
Power Liftgate
The power liftgate (PLG) system is activated through the use of the following: remote keyless entry (RKE), overhead console switches, outside liftgate handle switch or the DRBIII(R). These inputs are hardwired to the body control module (BCM) and can be monitored with a diagnostic tool. The BCM will send the message via PCI bus to the power liftgate module (PLGM). The liftgate must be in the full open or full closed position to operate. Once the BCM sends a button activation message to the PLGM, the module shall read all inputs, outputs and vehicle conditions to determine whether it shall open, close or inhibit the PLG operation. Once the PLGM determines the vehicle conditions are safe for operation, the PLGM will initiate a chime for 2 seconds prior to the liftgate activation and 2 seconds during the open or close cycle.
During an opening or closing cycle, the PLGM can detect an obstacle present should it meet sufficient resistance by the hall effect sensors (integrated in the gear motor assembly GMA).
During an open cycle, multiple liftgate activations (RKE, overhead console, B pillar) are ignored until the liftgate reaches the full open position. However, during a close cycle, a 2nd liftgate activation (RKE, overhead console, B pillar) will reverse the liftgate to the full open position.
If the engine is cranked during a power open/close the PLG will pause then resume after engine cranking. In addition, if the vehicle is placed in gear during an open cycle, the PLG shall reverse direction and begin closing. If the vehicle is placed in gear during a closing cycle, the PLG shall continue closing until fully closed. If the outside handle is activated during an open cycle, the PLG will become a full manual liftgate. If the outside handle is activated during a close cycle, the PLG shall reverse direction of travel to the full open position.
Diagnostic Features
The PLG can be flashed on vehicle via PCI bus with a DRBIII(R) diagnostic tool. The DRBIII(R) can read all inputs, actuate all outputs, read module information, and read diagnostic trouble codes. As a reminder, some DTC's can be set during normal PLG operation.
System Inhibitors
1. Battery voltage too high or too low (above 16V, below 9.5V)
2. Vehicle in gear
3. Vehicle speed > 0 MPH
4. Outside temperature too high or too low (above 143 °F, below -12 °F)
5. O/H console lockout will inhibit the B pillar switches only.
6. Liftgate locked will inhibit all interior switches from opening (overhead console). A locked liftgate can be power closed.
7. Pinch Sensor switch stuck shall inhibit the power close feature.
POWER SLIDING DOOR SYSTEM
Power Sliding Door
The Power Sliding Door (PSD) system is activated through the use of the following: Remote Keyless Entry (RKE), overhead console switches, B pillar switches or the DRBIII(R). These inputs are hardwired to the body control module (BCM) and can be monitored with a diagnostic tool. The BCM will send the message via PCI bus to the power sliding door module (PSDM). The sliding door must be in the full open or full closed position to operate. Once the BCM sends a button activation message to the PSDM, the module shall read all inputs, outputs and vehicle conditions to determine whether it shall open, close or inhibit the PSD operation. During an opening or closing cycle, the PSDM can detect an obstacle present should it meet sufficient resistance by the hall effect sensors (integrated in the drive motor).
During an open cycle, multiple door activations (RKE, overhead console, B pillar) are ignored until the door reaches the full open position. However, during a close cycle, a 2nd door activation (RKE, overhead console, B pillar) will reverse the door to the full open position.
If the engine is cranked during a power open/close the PSD will pause then resume after engine cranking. In addition, if the vehicle is placed in gear during an open cycle, the PSD shall reverse direction and begin closing. If the vehicle is placed in gear during a closing cycle, the PSD shall continue closing until fully closed.
If the inside or outside handle is activated during an open or close cycle, the PSD will become a full manual sliding door. When the child lock out switch is ON, the B pillar switches are disabled.
There is only one part number for the power sliding door module (PSDM). The driver sliding door harness has an additional ground circuit which will identify it as the driver side. This eliminates the need for a left and a right side module.
Diagnostic Features
The PSDM can be flashed on vehicle via PCI bus with a DRBIII(R) diagnostic tool. The DRBIII(R) can read all inputs, actuate all outputs, read module information, and read diagnostic trouble codes. As a reminder, some DTC's can be set during normal PSD operation.
System Inhibitors
1. Battery voltage too high or too low (above 16V, below 9.5V)
2. Vehicle in gear
3. Vehicle speed > 0 MPH
4. Child locks enabled inhibit the B pillar switch operation
5. O/H console lockout will inhibit the B pillar switches
6. Doors locked will inhibit all interior switches from opening (Overhead Console, B Pillar). A locked sliding door can be power closed.