instrument panel CHEVROLET DYNASTY 1993 Repair Manual

(f) If there is a difference in readings, check
printed circuit board for contact to cluster connec-
tors. (g) If OK and contacts are not distorted, replace
printed circuit board. (h) If everything checks out OK, refer to Sending
Unit Test.
(4) The Gauge Resistance Chart (Fig. 12), is gen-
eral guidelines for checking the gauge position
against the sending unit resistance. Because of only
a few specific points of gauge position versus sending
unit resistance, a good estimate is needed when the
resistance falls between graduations. Even when the
resistance corresponds to graduations, the gauge has
a tolerance of 64 ohms.
Volt gauge: The calibration dot on the volt gauge
corresponds to 13 volts between the gauge ignition
and ground pins. If voltage varies from this, estimate
proper gauge position with input voltage.
TACHOMETER AND TURBO GAUGE REMOVAL
(1) Remove switch pod assembly.
(2) Remove steering column trim cover.
(3) Remove cluster mask and lens assembly.
(4) Remove screws attaching tachometer to cluster
housing. (5) Pull tachometer rearward to remove.
(6) Disconnect turbo gauge hose. If turbo hose can-
not be disconnected, remove cluster. (7) For installation reverse above procedures.
TACHOMETER CIRCUIT TESTING
(1) Remove cluster. (2) Check for battery voltage at cavity 8 of the in-
strument cluster red connector (Fig.6). (3) With the ignition in the ON position, check for
battery voltage at cavity 9 of the instrument cluster
red connector. (4) Check cavity 14 of the instrument cluster red
connector for continuity to ground. (5) Check for tachometer signal from the power-
train control module by connecting an AC DIGITAL
VOLTMETER to cavity 6 of the instrument cluster
black connector and ground. A reading of at least 1.0
volt should be present with the engine running (Fig.
7). (a) If voltage is within specification, go to step 7.
(b) If voltage is NOT within specification, per-
form steps 6.
(6) If there is less than 1.0 volt at cavity 6, check
for continuity between cavity 6 and pin 43 of the
powertrain control module connector. (a) If continuity is OK, between cavity 6 and pin
43 of the powertrain control module connector, re-
place the powertrain control module. (b) No continuity check the connectors for dam-
aged pins or terminal push outs or defective wire.
(7) If all tests performed test good replace the ta-
chometer drive module. (8) If the tachometer continues to be inoperative,
replace the tachometer assembly.
VOLTMETER, TEMPERATURE GAUGE, OIL PRESSURE GAUGE AND FUEL GAUGEASSEMBLYÐREMOVAL
(1) Remove pod switch assembly.
(2) Remove steering column trim cover.
(3) Remove cluster mask and lens assembly.
(4) Remove screws attaching gauge assembly to
cluster. (5) Pull rearward to remove gauge assembly.
(6) For installation reverse above procedures.
SENDING UNIT TEST
It is not necessary to remove instrument clus-
ter from vehicle for gauge replacement. When removing gauge assemblies from cluster,
gauge must be pulled straight out, not twisted, or
damage to gauge pin may result. When a problem occurs with a cluster gauge, be-
fore disassembling the cluster to check the gauge,
check for a defective sending unit or wiring. (1) Sending units and wiring can be checked by
grounding the connector leads, at the sending unit,
in the vehicle. (2) With the ignition in the ON position; a
grounded input will cause the oil, fuel or tempera-
ture gauge to read at or above maximum.
Fig. 12 Gauge Resistance
8E - 46 INSTRUMENT PANEL AND GAUGES Ä

(3) With the ignition switch ON, an open (discon-
nected sending unit wire) causes the oil, fuel or tem-
perature gauge to read below low, empty or cold
indicators. (4) If steps 2 and 3 check OK, refer to the individ-
ual sending unit test procedures.
FUEL TANK SENDING UNIT TEST
Refer to Group 14, Fuel for test procedure.
CHECK GAUGES WARNING LAMP TESTS
The check gauges warning lamp will illuminated
when the ignition key is turned to the ON position.
The lamp will illuminate if the engine oil pressure
drops below a safe level. The check gauge lamp will
light for high engine temperature or for low voltage. To test the system turn ignition key to the ON po-
sition. If the lamp fails to light, inspect for a broken
or disconnected wire at the oil pressure combination
sending unit, which is located at the front of the en-
gine (Fig. 13). If the wire at the connector checks
good pull connector loose from the switch terminal
and with a jumper wire ground connector to the en-
gine. With the ignition key turned to the ON posi-
tion check the warning lamp. If lamp still fails to
light, inspect for a burned lamp. If lamp still fails to
light, inspect for a burned out lamp or disconnected
socket in the cluster.
To test the switch disconnect the switch electrical
connector. Attach positive lead of an ohmmeter to
the switch terminal for the gray (GY) wire and the
negative lead to an engine ground. With the engine
off, there should be continuity in the system. Start
the engine. With the engine running, the ohmmeter
should show no continuity. If the above results are
not obtained, replace the switch.
COMBINATION OIL SENDING UNIT TEST
The combination oil sending unit has two func-
tions: (1) The normal closed circuit keeps the oil pressure
warning lamp on until there is oil pressure. (2) The sending unit provides a resistance that
varies with oil pressure. To test the normally closed oil lamp circuit, discon-
nect the locking connector and measure the resis-
tance between the switch terminal and the metal
housing. The ohmmeter should read 0 ohms. Start
the engine (Fig. 14).
If there is oil pressure, the ohmmeter should read
an open circuit. To test the sending unit, measure the resistance
between the sending unit terminal and the metal
housing. The ohmmeter should read open. Start the
engine. The ohmmeter should read between 30 to 55 ohms,
depending on engine speed, oil temperature, and oil
viscosity. If the above results are not obtained, replace the
sending unit.
SEAT BELT WARNING SYSTEM
For testing of this system refer to Group 8U,
Chime Warning/Reminder System.
MALFUNCTION INDICATOR (CHECK ENGINE) SYSTEM
For testing this system refer to the Body Diagnos-
tic Procedures booklet.
BRAKE SYSTEM WARNING LAMP TEST
The brake warning lamp illuminates when parking
brake is applied with ignition key turned ON. The
same lamp will also illuminate should one of the two
service brake systems fail when brake pedal is ap-
plied. To test system turn ignition key ON, and ap-
ply parking brake. If lamp fails to light, inspect for a
burned out lamp, disconnected socket, a broken or
disconnected wire at switch. The lamp also lights
when the ignition switch is turned to START. Refer
to Brake System Warning Lamp Diagnosis Chart
(Fig. 15). To test service brake warning system, raise vehicle
on a hoist and open a wheel cylinder bleeder while aFig. 13 Combination Oil Sending Unit
Fig. 14 Combination Oil Sending Unit Test
Ä INSTRUMENT PANEL AND GAUGES 8E - 47

helper depresses brake pedal and observes warning
lamp. If lamp fails to light, inspect for a burned out
lamp, disconnected socket, a broken or disconnected
wire at switch.If lamp is not burned out and wire continuity is
proven, replace brake warning switch in brake line
TEE fitting mounted on frame rail in engine com-
partment below master cylinder (Fig.16).
CAUTION: If wheel cylinder bleeder was opened
check master cylinder fluid level.
SPEEDOMETER SYSTEM
The vehicles are equipped with electronically
driven speedometer and odometer assemblies. The
unit has the same appearance as a conventional
speedometer but it eliminates the cable-driven me-
chanical system. A signal is sent from a transmis-
sion-mounted vehicle speed sensor to the
speedometer circuitry through the wiring harness.
By eliminating the speedometer cable, instrument
cluster service and removal is improved. Refer to Fig.
17 Speedometer Diagnosis Chart. When the speedometer is out of calibration. The
electronic automatic transaxle vehicle speed sensor
output must be calibrated to reflect the different combinations of equipment. The procedure is called
Pinion Factor, refer to Group 21, Transaxle for the
procedure.
Fig. 15 Brake System Warning Lamp Diagnosis
Fig. 16 Brake Warning Lamp Switch
8E - 48 INSTRUMENT PANEL AND GAUGES Ä

SPEEDOMETER/ODOMETER ASSEMBLY REMOVAL
(1) Remove switch pod assembly.
(2) Remove cluster, refer to Cluster Removal.
(3) Remove mask and lens assembly.
(4) Remove tachometer, turbo gauge.
(5) Remove volt, temperature, oil and fuel gauge
assemblies. (6) Remove the speedometer/odometer assembly
from the cluster housing. (7) Disconnect pigtail connector from the cluster
printed circuit board. (8) For installation reverse above procedures. Lis-
ten for the pigtail connector to snap in place.
SPEEDOMETER CIRCUIT TESTING
(1) Using DRB II, check vehicle speed sensor for
speed sensor fault code and for proper speed indica-
tion. Refer to Powertrain Diagnostics Procedure
Manual; Speed Control Test (Fig. 18). (2) Remove cluster, but do not disconnect cluster
wiring. (3) With ignition ON check for battery voltage
across the ignition pin and ground pin of speedome-
ter connector. (4) Check for continuity from vehicle speed sensor
signal pin to connector at speed sensor. (5) Check cluster to body for continuity to ground.
(6) If all these tests prove good, replace speedome-
ter.
VEHICLE SPEED SENSOR REPLACEMENT
(1) Remove harness connector from sensor and
make sure weather seal is on harness connector. (2) Remove sensor retaining bolt (Fig. 19).
(3) Pull sensor and pinion gear assembly out of
transaxle. If necessary carefully pry loose with a flat
blade screwdriver (Fig. 20). (4) Remove pinion gear from sensor.
(5) For installation reverse above procedures. Seat
the sensor assembly by hand to ensure proper gear
engagement. Tighten retaining bolt to 7 N Im (60 in.
lbs.) torque.
ELECTRONIC AUTOMATIC TRANSAXLE VEHICLE SPEED SENSOR REPLACEMENT
The output vehicle speed sensor is located to the
left of the manual shift lever. (1) Raise and support vehicle on safety stands.
(2) Remove vehicle speed sensor (Fig. 21).
(3) For installation, reverse above procedures.
Fig. 17 Speedometer Diagnosis
Fig. 18 Speedometer
Ä INSTRUMENT PANEL AND GAUGES 8E - 49

VEHICLE SPEED SENSOR TEST
For testing of the vehicle speed sensor and related
components using DRB II, refer to the appropriate
Powertrain Diagnostics Test Procedure Manual.
TACHOMETER DRIVE MODULE REMOVAL
(1) Remove cluster assembly.
(2) Pull tachometer drive module from printed cir-
cuit board (Fig. 22). (3) For installation reverse above procedures. Use
care when aligning module to printed circuit board.
PRINTED CIRCUIT BOARD REMOVAL
(1) Remove cluster assembly.
(2) Remove mounting screws securing printed cir-
cuit board to cluster housing. (3) Remove tachometer drive module (Fig. 22).
(4) Twist out all lamp sockets.
(5) For installation reverse above procedures.
CLUSTER LAMPS REMOVALÐMECHANIALCLUSTER ONLY
(1) Remove cluster assembly (Fig. 23).
(2) Remove one piece integral lamp and socket
from rear of cluster.
ELECTRONIC CLUSTER
Refer to Body Diagnostic Procedures Manual when
using DRB II.
SELF DIAGNOSTIC SYSTEM
The electronic clusters have an internal diagnostic
routing to isolate problems within the cluster.
Fig. 20 Vehicle Speed Sensor and Speedometer Pinion
Fig. 21 Vehicle Speed Sensor Removal
Fig. 22 Cluster Printed Circuit Board
Fig. 19 Vehicle Speed Sensor and Connector
8E - 50 INSTRUMENT PANEL AND GAUGES Ä

Perform cluster Self Diagnostic Test to determine
whether problem is within cluster or outside of clus-
ter. Refer to Fig. 24 and 25.
Successful completion of the SELF DIAGNOSTIC
TEST indicates that the problem is in the wiring,
connectors or sensors out side of the cluster.
CLUSTER ASSEMBLY REMOVAL
The electronic cluster which is serviced as an as-
sembly is removed with the same procedure as the
conventional cluster.
CONDITION: CLUSTER DISPLAYS DO NOT ILLUMINATE AFTER VEHICLE IS STARTED
(1) Check fuses and verify battery and ignition
voltage at cluster connector. (2) Check ground from cluster connector to instru-
ment panel ground stud.
SWITCH AND PANEL COMPONENT SERVICE
HEADLAMP SWITCH
The headlamp switch is located on the left side of
the switch pod. The switch controls the headlamps,
parking lamps, fog lamps and instrument light dim- ming. If any of the switches require replacement the
entire headlamp switch assembly must be replaced
(Fig. 26 and 27).
REMOVAL
(1) Remove switch pod assembly from the instru-
ment panel. DO NOT attempt to remove instrument
cluster dimmer switch or wiper delay switch knob,
they are not removable. (2) Remove turn signal switch lever by pulling
straight out of switch pod. (3) Remove screws from bottom of switch pod.
(4) Separate inner and outer switch pod halves and
remove turn signal switch to gain access to screw. (5) Remove five inner switch pod panel screws and
3 screws from underneath the switch pod. Separate
the inner bezel from the outer bezel. (6) Remove switch mounting screws before discon-
necting linkage. (7) Disconnect switch linkage from buttons. Pull
the linkage straight up from the switch/button to dis-
engage it and remove switch.
Fig. 23 Mechanical Cluster Lamp Location
Ä INSTRUMENT PANEL AND GAUGES 8E - 51

Fig. 24 Electronic Cluster Self-Diagnostic Test
8E - 52 INSTRUMENT PANEL AND GAUGES Ä

Fig. 25 Electronic Cluster Self-Diagnostic TestÐContinued
Ä INSTRUMENT PANEL AND GAUGES 8E - 53

INSTALLATION (1) Latch switch linkage in the up position.
(2) Insert dimmer shaft into dimmer knob while
aligning switch in to switch pod assembly. (3) Install switch attaching screws.
(4) Unlatch linkage and install onto push buttons.
(5) Operate all switch modes for correct operation.
(6) Install turn signal switch.
(7) Reconnect wiring for turn signal switch, mak-
ing sure wire is properly clipped into position. (8) Place together the inner and outer bezels. In-
stall five inner switch pod panel screws and three
screws from underneath the switch pod. (9) Install turn signal lever by pushing straight
into switch assembly. (10) Install switch pod assembly.
LOWER STEERING COLUMN COVER REMOVAL
(1) Remove screws along top edge of cover.
(2) Remove screw at each lower corner of cover. (3) Remove cover from underneath over column
cover. (4) For installation reverse above procedures.
GLOVEBOX MODULE REMOVAL
(1) Disconnect battery negative cable and isolate
or remove fuse #26 prior to removing switch or wires
may short to ground. (2) Remove cowl side trim panel.
(3) Remove screws at right end of glovebox and
lower corners. (4) Open glovebox, remove light and disconnect
wiring. (5) Remove five screws along top of glovebox frame
and screw at each lower corner. (6) Remove glovebox assembly.
(7) For installation reverse above procedures.
CONCEALED HEADLAMP MODULE REMOVAL
(1) Remove left under panel silencer.
(2) Slide module off bayonet bracket while disen-
gaging spring retainer. (3) Disconnect wiring terminal.
(4) For installation reverse above procedures.
HOOD RELEASE REMOVE
(1) Remove lower column cover.
(2) Remove screws on fuse block and move aside.
(3) Remove screws on hood release assembly to re-
move. (4) For installation reverse above procedures.
AIR CONDITIONING CONTROL REMOVE
(1) Remove center stack bezel.
(2) Remove two control mounting screws (Fig. 28
and 29).
(3) Slide control rearward, disconnect cable, vac-
uum harness, and electrical wiring. With automatic
temperature control, disconnect wiring connector; be-
ing careful not to break off locking tab. (4) For installation reverse above procedures.
Fig. 26 Switch Pod Assembly
Fig. 27 Headlamp Multi-Function Switch
Fig. 28 A/C Control
8E - 54 INSTRUMENT PANEL AND GAUGES Ä

AUTOMATIC TEMPERATURE CONTROL LAMP REMOVAL
(1) Remove automatic temperature control from in-
strument panel. (2) Remove top cover screw and unsnap cover from
control (Fig. 30).
(3) Remove four screws that connect computer
housing to the button housing. (4) Unsnap the button housing from the computer
housing. (5) Remove lamps by turning in a counter clock-
wise direction and install lamps by turning in a
clockwise direction. (6) For installation reverse above procedures.
When finish perform ATC system function test.
GLOVE BOX LAMP AND SWITCH REMOVAL
(1) Disconnect battery negative cable and isolate
or remove fuse #26 prior to removing switch or wires
may short to ground. (2) Open glove box door. (3) Remove lamp and test. If bad replace lamp. If
OK proceed to step 3. (4) Carefully pry switch from its mounting surface
with tip of a small pry bar. (5) Remove switch from glove box and disconnect
electrical leads and test for battery voltage and
ground. (6) If OK test switch for continuity. If bad replace
switch. (7) For installation reverse above procedures.
ENGINE COMPARTMENT NODE
The Engine Compartment Node is a microcomputer
controlled unit which informs the EVIC overhead
console via the CCD bus of outside temperature, com-
pass direction and the following warning messages:
² Brake Fluid
² Low Coolant Level
² Low Engine Oil Level
The Engine Compartment Node is located behind
the front bumper reinforcement. For complete diagnostic procedures for the Engine
Compartment Node, refer to the AG and AJ Body Di-
agnostic Procedures Manual.
TRAVELER/EVIC REMOVAL
To test Traveler/EVIC, refer to AG, AJ Body Diag-
nostic Procedure. (1) Remove cluster stack bezel.
(2) Remove three screws and disconnect wiring
connector. (3) For installation reverse above procedures.
BEZEL WITH/WITHOUT MESSAGE CENTERREMOVAL
(1) Use a straight edge tool to pry out one end of
the message center and continue to disengage six
clips along the length of the message center. (2) Remove the message center and disconnect the
wiring. (3) For installation reverse the above procedures.
CONSOLE SWITCH PLATE/CUBBY BOXREMOVAL
(1) Pry up edge of switch plate or cubby box.
(2) Disconnect wiring terminal to switch plate if so
equipped. (3) For installation reverse above procedures.
CIGAR LIGHTER REMOVAL
(1) Remove center bezel.
(2) Remove two center console attaching screws.
(3) Remove ash receptacle/cup holder.
(4) Remove two screws underneath ash receptacle/
cup holder. (5) Remove ash receiver/bezel.
(6) Disconnect wiring connectors from lighter re-
ceptacle.
Fig. 29 Automatic Temperature Control
Fig. 30 Automatic Temperature Control Lamp
Ä INSTRUMENT PANEL AND GAUGES 8E - 55