1993 CHEVROLET DYNASTY sensor

OVERHEAD CONSOLE
CONTENTS
page page
AA BODY .............................. 1
AC AND AY BODY ....................... 6 AG AND AJ BODIES
.................... 13
AP BODY ............................. 21
GENERAL INFORMATION AA BODY
INDEX
page page
Ambient Temperature Sensor ................ 6
Compass Calibration ....................... 2
Compass Diagnostics ...................... 5
Compass Module Replacement ............... 6
Demagnetizing Procedure ................... 4 Map Reading Lamps
....................... 1
Overhead Console Replacement .............. 5
Self-Diagnostic Test ....................... 5
Thermometer and Compass Operation ......... 1
Variance ................................ 2
MAP READING LAMPS
The map reading and rear passenger lamps are
turned on and off by pressing their individual switch
marked LAMP. These same lamps also serve as cour-
tesy lamps whenever a door is opened, the illumi-
nated entry system is activated, or the headlamp
switch is turned fully clockwise.
LAMP REPLACEMENT
(1) Remove lens by inserting a large paper clip or
wire, with a hook on the end, into the hole in the
lens and pull downward (Fig. 1).
(2) Remove lamp by pulling firmly toward front of
vehicle. (3) Install new lamp by pushing firmly into recep-
tacle. (4) Snap lens into position taking care to orient
the tabs on the lens with the slots in the housing and
snap into position.
LAMP TEST
(1) Close vehicle doors.
(2) Press each lamp switch button (Fig.2). Right
hand button should light passenger side lamp and
left hand button should light drivers side lamp front
or rear. (3) If any of the lamps fail to illuminate, open ve-
hicle doors: (a) If lamp does not illuminate check for a
burned out lamp. If lamp is OK, check fuse and
wire connectors. (b) If lamp illuminates when doors are open
check switch.
THERMOMETER AND COMPASS OPERATION
The ignition switch must be in the ON or ACCES-
SORY position before the temperature and compass
reading can be displayed. The Comp/Temp switch, lo-
cated left of the display module, turns the display on
and off. The US/Metric switch, located right of the dis-
play, changes the temperature reading from Fahrenheit
to Celsius. Should the compass blank out and the CAL
symbol only light, demagnetizing may be necessary.
The compass is a flux-gate system which, is inte-
gral to the console. The temperature readout is con-
nected to a thermistor sensor which, located on the
front lower radiator closure panel.Fig. 1 Overhead Console Lens Removal
Ä OVERHEAD CONSOLE 8C - 1

When the vehicle is standing still, engine compart-
ment temperature may be radiated to the tempera-
ture sensor. Therefore the most accurate ambient
temperature readings are displayed when the vehicle
is moving in a forward motion. When the ignition switch is turned off the last dis-
played temperature reading stays in memory. When
the ignition switch is turned on again the thermom-
eter will display the memory temperature for 1
minute; then update the display to the actual tem-
perature within 5 minutes. Refer to Compass and
Thermometer Diagnosis (Fig. 3).
COMPASS CALIBRATION
The compass unit automatically calibrates itself as
the vehicle is driven; therefore, no calibration should be
required. When the compass is first powered up, the
CAL light on the display should be on. The CAL light
will go off and the compass will be accurate after the
vehicle completes one to three complete circles.
Do not attempt to set the compass near large metal
objects, such as, other vehicles, large buildings, or
bridges. If the vehicle's compass headings are inaccurate,
the compass also can be manually calibrated using
the following procedures: (1) Depress and hold down both the Comp/Temp
button and the U.S./Metric button. (2) The display will go off and after 5 seconds the
VAR light will come on. Continue to hold both but-
tons down. (3) In approximately 10 seconds, the CAL light
will come on. Release both buttons and the display
will show the heading and outside temperature. (4) Release buttons the CAL light will then go off,
showing the compass is calibrated. (5) The variation may need to be adjusted. The
variation is the difference between magnetic north
and true north. To set variation refer the to Varia-
tion Setting Procedure. If the compass portion of the display is not lit or
compass readings are not accurate after calibration.
The vehicle may have too much magnetism for the
compass to be accurate or the compass circuitry is
not working properly. Refer to Variance Procedure,
Demagnetizing Procedure and/or Compass Diagnos-
tics.VARIANCE
Variance is the difference between magnetic North
and geographic North. In some areas the difference
between magnetic and geographic north is great
enough to cause the compass to give false readings. If
this occurs, the variance must be set.
Fig. 2 Map Lamp Diagnosis
8C - 2 OVERHEAD CONSOLE Ä

COMPASS MODULE REPLACEMENT
(1) Remove overhead console.
(2) Using a small screwdriver, release the 2 snaps
at rear of compass module. (3) After releasing the 2 snaps, slide compass mod-
ule rearward until free of mounting bar. (4) For installation reverse above procedures.
AMBIENT TEMPERATURE SENSOR
(1) Raise and support vehicle on safety stands.
(2) From behind front bumper fascia, remove screw
attaching sensor to front lower crossmember (Fig. 7). (3) For installation, reverse above procedures.
AC AND AY BODY
INDEX
page page
Ambient Temperature Sensor ............... 12
Automatic Calibration Set Procedure ........... 8
Bezel/Button Switch Removal ............... 10
Bus Accessed Diagnostics .................. 10
Console Removal ........................ 10
Electronic Board Assembly Replacement ....... 10
Electronic Vehicle Information Center (EVIC) Overhead Console ....................... 6 Engine Compartment Node Removal
.......... 12
EVIC Self Check Diagnostics ................ 8
Manual Calibration Set Procedure ............. 8
Map Reading Lamps/Power Sunroof Switch Removal .............................. 11
Overhead Reading/Courtesy Lamp Console ..... 11
Wiring Harness Removal ................... 10
ELECTRONIC VEHICLE INFORMATION CENTER
(EVIC) OVERHEAD CONSOLE
The Electronic Vehicle Information Center is a
computer controlled warning system which, monitors
various sensors used on the vehicle. The system sup-
plements the warning indicators in 8the instrument
cluster. Visual warning messages are displayed by a
digital display in the overhead console (Fig. 1).
When a warning message has been activated, a
tone will sound to attract the driver's attention. The
warning message will then be displayed on the over-
head console until the condition is corrected or a new
display function is called up. A tone will announce each new warning condition.
For complete diagnostic procedures for the EVIC
systems, refer to the Body-Chassis Diagnostic Test
Procedures Manual. The EVIC has a 24 function system that provides
the driver with visual messages when a warning con-
dition exists. These messages are displayed on the
overhead console. For complete EVIC overhead console operating in-
structions, refer to the Owners Manual provided with
the vehicle.
EVIC BUTTON FUNCTIONS
TIME button will display:
² Time of day
² Day of week
² Day of month
² Month of year
The body controller is the source of this informa-
tion. The EVIC function buttons are used to reset
and display this data.
² To set HOURS, press TIME button and within four
seconds press the SET button. An arrow will appear
on the display and point to the hours. Press and hold
the SET button to advance the hours or INFO button
to set back the hours.
² To set MINUTES, press TIME button. The arrow
will point to the minutes. Press and hold the SET
button to advance the minutes or INFO button to set
back the minutes.
Fig. 7 Ambient Temperature Sensor
Fig. 1 EVIC Overhead Console
8C - 6 OVERHEAD CONSOLE Ä

² To set DAY of WEEK, press TIME button. An ar-
row will appear on the display and point to the Day.
Press and hold the SET button to move the day for-
ward or INFO button to move it backward.
² To set DAY of MONTH, press TIME button. The
arrow will point to Date. Press and hold the SET
button to advance the date or INFO button to move
it backwards.
² To set MONTH of YEAR, press TIME button. The
arrow will point to the Month. Press and hold the
SET button to advance the Month forward or INFO
button to move backward. TEMP button, pressing the Temp button will dis-
play:
² The temperature outside the vehicle
² Vehicle direction define by an eight point compass
If Compass has lost calibration or not receiving
good information from the engine compartment node,
an asterisk (*) will flash on the display and the word
calibrate will appear. Refer to Compass Calibration. FUEL BUTTON, WILL DISPLAY:
² Pressing FUEL button the first time will show, the
estimated number of miles that can be driven with
the remaining fuel. The destination to empty indica-
tion will vary every few seconds as the amount of
fuel and fuel efficiency is calculated. This function
can not be reset.
² Pressing the FUEL button second time; will dis-
play the fuel consumed.
²
Pressing the FUEL button third time; will display
the average fuel economy in miles per gallon since last
reset. The display will be updated every 16 seconds.
² Pressing the FUEL button forth time, the current
fuel economy will be displayed. The current fuel
economy will be up updated every two seconds.
² To reset Fuel consumed, press SET button until
the fuel consumed message is displayed and then
within five seconds press SET button.
² To reset AVERAGE FUEL ECONOMY, press the
FUEL button until average fuel economy is displayed
and within five seconds press SET button. TRIP RESET, press FUEL button and wait four
seconds press the SET button twice. This clears all
trip information and the message Trip Reset will be
displayed. This will occur only if a reset function is
currently being displayed. The reset functions:
² Fuel consumed
² Average fuel economy message
INFO button, will active a MONITORED SYS-
TEMS OK message on display if all monitored sys-
tems are operating properly. If a problem is detected,
the appropriate message will be displayed. SET button, will clear the various functions after
they have been displayed. It is used to enter the
clock set or compass variance modes. This button is
also used to reset certain trip computer functions and
the maintenance reminder message.
The EVIC display may be turned off by pressing the
TIME and SET buttons at the same time. Pressing the
buttons a second time will restore the display.
EVIC INFORMATION SOURCES
The EVIC monitors information provided by the
body controller, engine compartment node and pow-
ertrain control module. Refer to Body Diagnostic Test
Procedure Manual for test procedures. The Body Controller is a micro-controller unit
which, informs the EVIC overhead console via the
CCD bus of:
² Time of day
² Day of week
² Day of month
² Month of year
² Fuel range
² Fuel consumed
² Fuel efficiency
² Warning messages as noted in Fig. 2
The Engine Compartment Node is a microcomputer
controlled unit which, informs the EVIC overhead
console via the CCD bus of:
² Outside temperature
² Compass direction
THE FOLLOWING ARE WARNING MESSAGES:
² Low brake fluid
² Low coolant level
² Low engine oil level
The powertrain control module is a microcomputer
controlled unit which, informs the EVIC overhead con-
sole via the CCD bus of the following warning messages:
² Engine temperature high
² Voltage improper
Fig. 2 EVIC Messages and Sensors
Ä OVERHEAD CONSOLE 8C - 7

VISUAL MESSAGES
Following are the visual messages and the condi-
tions under which, the messages will be given:
² Keys in ignition
² Exterior lamps on
These messages will appear if the conditions are
present and the driver's door is open while the igni-
tion switch is in the OFF, LOCK, or ACC positions.
A tone will sound until the condition is corrected or
the door is closed.
² Passenger door ajar
² Driver door ajar
² Trunk ajar
² Park brake engaged
² Right rear door ajar
² Left rear door ajar
These messages will appear if a condition is de-
tected after the vehicle is in motion. When the con-
dition is corrected, a short tone will sound to
acknowledge the action. LOW OIL PRESSURE
If this message is displayed while the vehicle is at
cruising speeds, immediate attention is required. If
this message appears at idle speed, increase the idle
speed and the message should go off. If the message
remains on, immediate attention is required. ENGINE TEMP CRITICAL
This message appears when a sensor has determined
that the engine coolant is overheating. If this message
comes on and stays on, immediate action is required.
COOLANT LEVEL LOW
LOW FUEL LEVEL
LOW BRAKE FLUID
WASHER FLUID LOW
These messages will appear if a continuous warn-
ing condition is detected while the engine is running.
Inspection is required. To clear this message from
the display, after the condition is corrected, the igni-
tion switch must be turned OFF. CHECK TRANS
This message will appear if a continuous warning
condition is detected while the engine is running. Im-
mediate attention is recommended. To clear this mes-
sage from the display, after the condition has been
corrected, the ignition switch must be turned OFF. VOLTAGE IMPROPER
This message will appear if a continuous warning
condition is detected. Immediate attention is re-
quired. To clear this message from the display, after
the condition has been corrected, the ignition switch
must be turned OFF. TURN SIGNAL ON
This message will appear if the turn signal is left
on while vehicle speed is over 15 mph and the vehi-
cle has traveled over one-half mile. FASTEN SEAT BELTS An intermittent chime tone will sound for several
seconds if the seat belt is not fastened. CHK ENGINE OIL LEVEL
If this message is delivered, a check of the engine
oil dipstick is suggested. To clear this message, after
the condition is corrected, the ignition switch must
be turned OFF. HEADLAMP OUT
BRAKE LAMP OUT
TAIL LAMP OUT
These conditions are monitored only when the lamps
are on. The message will remain, even after the lamp is
replaced, until the lamp is turned on and operates.
SERVICE REMINDER
The maintenance reminder statement is programmed
to provide general information only. Refer to Group 0,
Lubrication & Maintenance for specific vehicle require-
ments.
The service reminder message is displayed at 7,500
miles or 12 months intervals, which ever comes first. MONITORED SYSTEMS OK
If there is no warning condition to report, the mes-
sage Monitored Systems OK is displayed (Fig. 2).
AUTOMATIC CALIBRATION SET PROCEDURE
The engine compartment node will continuously
and automatically recalibrate the compass under nor-
mal driving conditions. As long as the vehicle is
turning, the engine compartment node will record
new compass data. This new data will be used to
recalibrate the compass at a rate of at least once per
full (360 degree) turn of the vehicle. Automatic cali-
bration does not require operator interface.
MANUAL CALIBRATION SET PROCEDURE
Manual compass calibration has been replaced by
automatic calibration set procedure. The manual cal-
ibration set procedure is available, but no longer
serves any useful purpose.
EVIC SELF CHECK DIAGNOSTICS
Ignition switch ON, the EVIC not displaying any
message, may imply a system failure and not an
EVIC failure. Turn the ignition OFF, close all vehi-
cle doors and wait at least 60 seconds before begin-
ning test. Turn ignition switch to the ON position.
Pressing the TEMP, FUEL and INFO buttons at the
same time shall provide the visual message MOD-
ULE SELF CHECK for two seconds. Following at
two second interval there will be messages:
² E2-0 SELF CHECK
² E3-0 SELF CHECK
² END OF SELF CHECK
Showing the microcomputer is working properly.
When the self check mode and message shows:
² E2-1
² E3-2
This would show a fault exists in the EVIC's micro-
computer and the EVIC should be replaced (Fig. 3).
8C - 8 OVERHEAD CONSOLE Ä

AMBIENT TEMPERATURE SENSOR
(1) Remove screws attaching grille and remove
grille. (2) Remove screw attaching sensor to radiator clo-
sure panel (Fig. 8). (3) For installation, reverse above procedures.
ENGINE COMPARTMENT NODE REMOVAL
(1) Remove screws attaching grille and remove
grille. (2) Disconnect wire harness connector.
(3) Remove screw attaching engine compartment
node to the closure panel (Fig. 9). (4) For installation, reverse above procedures.
Fig. 8 Ambient Temperature SensorFig. 9 Engine Compartment Node
8C - 12 OVERHEAD CONSOLE Ä

AG AND AJ BODIES INDEX
page page
Ambient Temperature Sensor Removal ......... 20
Compass Calibration ...................... 16
Compass Diagnostics ...................... 18
Compass Module Replacement .............. 20
Demagnetizing Procedure .................. 17
Electronic Vehicle Information Center (EVIC) ..... 13
Electronic Vehicle Information Center (EVIC) Removal .............................. 20 Engine Compartment Node (ECN)
............ 15
Engine Compartment Node Compass Calibration . 16
Engine Node Sensor Removal ............... 20
Map Reading Lamps ...................... 13
Overhead Console Replacement ............. 20
Thermometer and Compass ................. 16
Variance Procedure ....................... 17
MAP READING LAMPS
The map lamps are actuated by pressing on the lens.
These same lamps also serve as courtesy lamps when-
ever a door is opened. The illuminated entry system is
activated, or the headlamp switch is turned fully
clockwise (Fig. 1).
LAMP REPLACEMENT
(1) Remove lens by inserting a screw driver or knife
blade into slot located along-side of lens. Once screw-
driver is inserted pry lens to the side and swing down
as it unhooks from housing edge. (2) Remove lamp by pulling straight down.
(3) Install new lamp by pushing firmly into recep-
tacle. (4) Snap lens into position taking care to orient the
tabs on the lens with the slots in the housing.
LAMP TEST
(1) Close vehicle doors.
(2) Press each lamp switch. Right hand switch
should light passenger lamp and left hand switch
should light drivers lamp. (3) If either of the lamps fail to illuminate, open
vehicle doors. (a) If lamp does not illuminate check for a burned
out lamp. (b) If lamp illuminates when doors are open check
switch and wiring.
ELECTRONIC VEHICLE INFORMATION CENTER
(EVIC)
The Electronic Vehicle Information Center is a com-
puter controlled warning system which, monitors vari-
ous sensors used on the vehicle. The system supple-
ments the warning indicators in the instrument
cluster. Visual warning messages are displayed by a
digital display (Fig. 2).
When a warning message has been activated, a tone
will sound to attract the driver's attention. The warn-
ing message will then be displayed on the EVIC center
until the condition is corrected or a new display func-
tion is called up. A tone will announce each new
warning condition. For complete diagnostic procedures for the EVIC
systems, refer to the Body-Chassis Diagnostic Test
Procedures Manual. The EVIC has a 24 function system that provides the
driver with visual messages when a warning con-
Fig. 1 Overhead Console Lamp Replacement
Fig. 2 EVIC
Ä OVERHEAD CONSOLE 8C - 13

VISUAL MESSAGES
Following are the visual messages and the condi-
tions under which, the messages will be given:
² Keys in ignition
² Exterior lamps on
These messages will appear if the conditions are
present and the driver's door is open while the igni-
tion switch is in the OFF, LOCK, or ACC positions.
A tone will sound until the condition is corrected or
the door is closed.
² Passenger door ajar
² Driver door ajar
² Trunk ajar
² Park brake engaged
² Right rear door ajar
² Left rear door ajar
These messages will appear if a condition is de-
tected after the vehicle is in motion. When the con-
dition is corrected, a short tone will sound to
acknowledge the action. LOW OIL PRESSURE
If this message is displayed while the vehicle is at
cruising speeds, immediate attention is required. If
this message appears at idle speed, increase the idle
speed and the message should go off. If the message
remains on, immediate attention is required. ENGINE TEMP CRITICAL
This message appears when a sensor has deter-
mined that the engine coolant is overheating. If this
message comes on and stays on, immediate action is
required. COOLANT LEVEL LOW
LOW FUEL LEVEL
LOW BRAKE FLUID WASHER FLUID LOW
These messages will appear if a continuous warn-
ing condition is detected while the engine is running.
Inspection is required. To clear this message from
the display, after the condition is corrected, the igni-
tion switch must be turned OFF. CHECK TRANS
This message will appear if a continuous warning
condition is detected while the engine is running. Im-
mediate attention is recommended. To clear this mes-
sage from the display, after the condition has been
corrected, the ignition switch must be turned OFF. VOLTAGE IMPROPER
This message will appear if a continuous warning
condition is detected. Immediate attention is re-
quired. To clear this message from the display, after
the condition has been corrected, the ignition switch
must be turned OFF. TURN SIGNAL ON
This message will appear if the turn signal is left
on while vehicle speed is over 15 mph and the vehi-
cle has traveled over one-half mile. FASTEN SEAT BELTS
An intermittent chime tone will sound for several
seconds if the seat belt is not fastened. CHK ENGINE OIL LEVEL
If this message is delivered, a check of the engine
oil dipstick is suggested. To clear this message, after
the condition is corrected, the ignition switch must
be turned OFF. HEADLAMP OUT
BRAKE LAMP OUT
TAIL LAMP OUT
These conditions are monitored only when the
lamps are on. The message will remain, even after
the lamp is replaced, until the lamp is turned on and
operates. SERVICE REMINDER
The maintenance reminder statement is pro-
grammed to provide general information only. Refer
to Group 0, Lubrication & Maintenance for specific
vehicle requirements. The service reminder message is displayed at 7,500
miles or 12 months intervals, which ever comes first. MONITORED SYSTEMS OK
If there is no warning condition to report, the mes-
sage Monitored Systems OK is displayed (Fig. 3).
ENGINE COMPARTMENT NODE (ECN)
The Engine Compartment Node is a microcomputer
controlled unit which, informs the Electronic Vehicle
Information Center (EVIC) via the CCD bus of:
² Outside temperature
² Compass direction
and the following warning messages:
² Low Brake Fluid
² Low Coolant Level
² Low Engine Oil Level
Fig. 3 EVIC Messages and Sensors
Ä OVERHEAD CONSOLE 8C - 15