Driver/Vehicle Information Display: Description and Operation
DIGITAL I/PThe Digital Electronic Instrument Panel contains vacuum fluorescent displays for the Speedometer, Fuel Gage, Oil Pressure Gage, Temperature Gage and Voltmeter.
The Turn Lamps, Safety Belt Lamp, SERVICE ENGINE SOON Lamp, BRAKE Lamp, Headlamp High Beam Indicator and SHIFT Lamp (manual transmission) use standard bulbs and operate the same as the Base and Gage Clusters.
Battery voltage to the Cluster is supplied by the ORN (40) wire. This circuit voltage is used for the memory to maintain the total and trip mileages for the odometers.
Ignition voltage to the Cluster is supplied by the PNK/WHT (39) wire. This circuit supplies voltage to the vacuum fluorescent displays and the BRAKE and SERVICE ENGINE SOON indicators and the Voltmeter.
The other circuits to the Cluster provide the various signals necessary to operate the displays and indicators.
When the Ignition Switch is turned to RUN, all of the segments of the vacuum fluorescent displays are displayed for about two seconds. The displays then indicate current levels.
The vacuum fluorescent displays can be switched between English and Metric by the E/M switch. When the E/M switch is open, the displays are in English. When the E/M switch is closed, the displays are in Metric.
CLUSTER DIMMING
When the Ignition Switch is in RUN, the displays are at full brightness. When the Light Switch is in PARK or HEAD, the Cluster senses that the lights are on through the BRN (9) wire. This allows the display brightness to be controlled by the Panel and Interior Lamp Switch through the GRA (9) wire.
SPEEDOMETER/ODOMETER/TRIP ODOMETER
These displays receive a signal from the Vehicle Speed Sensor Buffer (DRAC) through the LT BLU/BLK (824) wire. The Vehicle Speed Sensor Buffer (DRAC) converts the speed signal from the Vehicle Speed Sensor to 4000 pulses per mile. A different Vehicle Speed Sensor Buffer (DRAC) is used for each axle ratio to convert the signal.
The Speedometer indicates vehicle speed in miles per hour or kilometers per hour depending on the E/M Switch position. Speeds below 1.4 mph may be displayed as "0."
The odometer/trip odometer display is mounted on a separate board attached to the main display board. The odometer displays the total vehicle mileage up to 999,999 miles in the English mode. If the mileage exceeds this, the display flashes ERROR. In Metric mode, the display will flash ERROR when it exceeds 999,999 kilometers. The English display will show the normal display.
The display can be switched from total odometer to trip odometer by pushing the trip switch. When the TRIP Switch is open, the total mileage is displayed. When the TRIP Switch is closed, the trip mileage is displayed.
The Trip Odometer can be reset to 0 by pushing the RESET Switch. The display must be in the TRIP mode to be reset.
The accumulated mileage of the two displays is gored in a nonvolatile memory chip to prevent losing this data if the battery or cluster is disconnected.
If the Cluster is replaced, the Odometer Display can be transferred to the new cluster.
FUEL GAGE DISPLAY
The Fuel Gage Display shows the fuel level in the tank. This signal is supplied to the Cluster through the PNK (3O) wire. With low fuel level in the tank, the sender resistance is low. With high fuel level in the tank, the sender resistance is high. If the fuel level in the fuel tank drops below approximately 11 liters (3 gallons) in a 75-liter (20-gallon) tank, a box around the Fuel Gage ISO Symbol flashes to indicate low fuel level.
OIL PRESSURE GAGE DISPLAY
The Oil Pressure Gage Display shows the engine operating oil pressure. This signal is supplied to the Cluster through the TAN (31) wire. With low oil pressure, the sender resistance is low. With high oil pressure, the sender resistance is high. If engine oil pressure drops below 69 kPa (10 psi), a box around the Oil Pressure Gage ISO Symbol flashes to indicate low oil pressure.
COOLANT TEMPERATURE GAGE DISPLAY
The Coolant Temperature Gage Display shows the engine coolant temperature. This signal is sent to the cluster through the DK GRN (35) wire. With low coolant temperature, the sender resistance is high. With high coolant temperature the sender resistance is low.
If the coolant temperature exceeds 118°C (245°F), a box around the Coolant Temperature Gage ISO Symbol flashes to indicate an engine overheat condition.
VOLTMETER DISPLAY
The Voltmeter Display shows the battery voltage. The Voltmeter is connected to the PNK/BLK (39) wire and the BLK (150) wire.
If the generator output is high, low or 0 volts, a box around the Voltmeter ISO Symbol flashes to indicate a problem with the charging system. This signal is sent to the cluster through the BRN (25) wire.
TACHOMETER DISPLAY
The Tachometer Display shows engine revolutions per minute (RPM). The Tachometer is connected to the WHT (121) wire.
The Tachometer has a total range of 0-5500 RPM. The YELLOW warning region has a range of 4500-5000 RPM and the RED warning region has a range of 5000-5500 RPM.