brake CHEVROLET DYNASTY 1993 Service Manual

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.
BRAKE SYSTEM WARNING LAMP
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. To test service brake warning system, raise vehicle
on a hoist and open a wheel cylinder bleeder while a
helper depresses brake pedal and observes warning
light. 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 compart-
ment below master cylinder (Fig.6 and 7). CAUTION: If wheel cylinder bleeder was opened
check master cylinder fluid level.
SEAT BELT WARNING LAMP
For testing of this system, refer to Group 8M, Re-
straint System.
MALFUNCTION INDICATOR (CHECK ENGINE) LAMP
For testing of this system, refer to the Powertrain
Diagnostic Test Procedure Manual.
MECHANICAL/ELECTRONIC CLUSTER REMOVAL
CLUSTER BEZELS REMOVAL
(1) Move gear selector to the low position.
(2) Remove five screws attaching upper bezel to in-
strument panel (Fig. 8). (3) Lift cluster bezel over steering wheel.
(4) Remove four screws attaching lower bezel to in-
strument panel. (5) Lift lower cluster bezel from instrument panel.
(6) For installation reverse above procedures.
CLUSTER MASK AND LENS REMOVAL
(1) Remove cluster bezel.
(2) Remove trip reset knob by pulling straight
back. (3) Remove five screws attaching mask and lens to
cluster. (4) For installation reverse above procedures.
Fig. 4 Combination Oil Sending Unit
Fig. 5 Combination Oil Sending Unit Test
Fig. 6 Brake Warning Lamp Switch
Ä INSTRUMENT PANEL AND GAUGES 8E - 25

CLUSTER ASSEMBLY
REMOVALÐCLUSTER WITH TRANSMISSION RANGE
INDICATOR FROM STEERING COLUMN (1) Disconnect battery to assure no air bag system
fault codes are stored. (2) Remove cluster bezel (Fig. 9).
Fig. 7 Brake System Warning Lamp Diagnosis
Fig. 8 Cluster Bezel
Fig. 9 Instrument panel Bezels
8E - 26 INSTRUMENT PANEL AND GAUGES Ä

(3) Remove switch assembly and escutcheon from
switch module by removing four attaching screws
(Fig. 37).
(4) Remove headlamp switch mounting plate from
switch by removing retaining nut. (5) For installation reverse above procedures.
REAR WINDOW DEFOGGER SWITCHREPLACEMENT
(1) Remove headlamp and accessory switch module
from instrument panel (Fig. 36). (2) Remove rear window defogger switch by de-
pressing snap-in clips on top and bottom of switch. (3) For installation reverse above procedures.
HOOD RELEASE HANDLE AND CABLEREPLACEMENT
(1) Disconnect hood release cable at hood latch.
(2) Remove two screws from underside of hood re-
lease handle. (3) Pull mechanism assembly rearward to remove.
(4) For installation reverse above procedures.
PARK BRAKE RELEASE HANDLE AND LINK REPLACEMENT
(1) Remove left side under panel silencer.
(2) Remove park brake link from lever on park
brake mechanism. (3) Remove upper and lower cluster bezels.
(4) Pull park brake release handle and remove
screw. (5) Remove column cover/park brake release han-
dle assembly by removing four remaining screws. (6) For installation reverse above procedures.
LAMP OUTAGE MODULE REPLACEMENT
(1) Disconnect battery negative cable and isolate
or remove fuse #13 prior to removing switch or wires
may short to ground. (2) Remove lower right instrument panel silencer.
(3) Remove glove box and ash receiver module.
(4) Remove three screws attaching the mounting
bracket to instrument panel. (5) Lower bracket and module assembly, to discon-
nect wire connectors. (6) Remove two screws attaching the Lamp Outage
Module to bracket. (7) Remove two screws attaching the security mod-
ule to bracket. (8) To installation reverse above procedures.
BODY CONTROLLER REPLACEMENT
(1) Remove right side door sill and kick panel trim
five screws (Fig. 38).
(2) Disconnect body controller wiring.
(3) Remove controller retaining nuts.
(4) For installation reverse above procedures.
GLOVE BOX/ASH RECEIVER ASSEMBLY REPLACEMENT
(1) Disconnect battery negative cable and isolate
or remove fuse #13 prior to removing switch or wires
may short to ground. (2) Remove center support cover/floor console as
necessary. (3) Disconnect glovebox/Ash receiver wiring con-
nectors (Fig. 39). (4) Remove ten screws around edge of glovebox/ash
receiver assembly. (5) Remove glovebox/ash receiver module from in-
strument panel. (6) For installation reverse above procedures.
Fig. 37 Headlamp and Accessory Switch
Fig. 38 Body Controller Location
Ä INSTRUMENT PANEL AND GAUGES 8E - 39

ELECTRONIC DIGITAL CLOCK
The electronic digital clock is in the radio. The
clock and radio each use the display panel built into
the radio. A digital readout indicates the time in
hours and minutes whenever the ignition switch is in
the ON or ACC position. When the ignition switch is in the ON or OFF po-
sition, or when the radio frequency is being dis-
played, time keeping is accurately maintained. The procedure for setting the clock varies slightly
with each radio. The correct procedure is described
under the individual radio operating instructions re-
ferred to in the Owner's manual supplied with the
vehicle.
WARNING LAMPS
The AG & AJ Body instrument clusters have warn-
ing lamps or indicators with the electronic cluster for
six different systems. These include low oil pressure,
check gauges, brake system, air bag, seat belt, mal-
function indicator (check engine) lamp.
CLUSTER AND GAUGE SERVICE AND TESTING
CAUTION: Disconnect negative battery cable, in en-
gine compartment, before servicing instrument
panel. When power is required for test purposes,
reconnect battery cable for test only. Disconnect negative battery cable after test and be-
fore continuing service procedures. It is not necessary to remove instrument cluster
from vehicle for gauge replacement. Gauges must be pulled straight out, when remov-
ing or pins may be damaged.
SWITCH POD ASSEMBLY REMOVAL
(1) Disconnect negative battery cable.
(2) Pry up edge of panel vent grille, using a
straight flat edge tool to disengage clips, then re-
move grille (Fig. 4). (3) Remove two screws located under panel vent
grille. (4) Remove two screws underneath switch POD as-
sembly. (5) With tilt steering adjust steering wheel to the
lowest setting. (6) Pull switch module rearward to remove module
and disconnect all wire connections. (7) For Installation reverse above procedures.
Tighten all screws to 2 N Im (20 in. lbs.) torque.
MECHANICAL/ELECTRONIC CLUSTER REMOVAL
CLUSTER MASK AND LENS REMOVAL
(1) Remove switch pod assembly (Fig. 4).
(2) Remove tilt column lever if equipped.
(3) Remove steering column trim cover.
Fig. 4 Switch POD Assembly
Ä INSTRUMENT PANEL AND GAUGES 8E - 43

(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

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

(7) Unscrew lighter receptacle shell from element
and remove. (8) For installation reverse above procedures.
INSTRUMENT PANEL ROLL DOWN PROCEDURE
CAUTION: Disconnect negative battery cable, in en-
gine compartment, before servicing instrument
panel.
(1) Remove instrument panel center bezel (Fig.
31). (2) Remove upper and lower steering column cov-
ers. (3) Remove the left under panel silencer.
(4) Set parking brake.
(5) Remove console side carpet panels (Fig. 32).
(6) Remove console, refer to Group 23, Body.
(7) Remove transmission range clip and cable loop
end from post on gear shifter (Fig. 33 and 34). (8) Remove adjuster from tab on gear shifter
bracket. By pushing in locking knob on adjuster, and
sliding the adjuster off the tab on the gear shifter
bracket. (a) For installation: insert transmission range
cable into adjuster and line up with the end of the
adjuster. (b) The transmission range indicator must be ad-
justed with the gear shifter in low position. (c) Check the gear selector indicator for proper
alignment. (d) Attach transmission range clip to the ad-
juster to secure cable.
(9) Remove two screws and slide Air Bag Diagnos-
tic Module out of right side of instrument panel cen-
ter stack area, then disconnect wiring. (10) Remove screw from instrument panel dimmer
module at left of steering column and lower module.
Fig. 31 Instrument Panel Components
Fig. 32 Center Console
8E - 56 INSTRUMENT PANEL AND GAUGES Ä

AP BODY INDEX
page page
Cluster and Gauge Service and Testing ....... 58
Gauges ................................ 61
General Information ....................... 58 Instrument Panel Replacement
.............. 72
Interior Lamp Replacement ................. 73
Switch and Panel Component Service ......... 67
GENERAL INFORMATION
INSTRUMENT CLUSTER
There are two conventional instrument cluster as-
semblies available. The clusters incorporates mag-
netic type gauges and an electronically driven
speedometer and odometer assembly (Fig. 1 and 2).
MAGNETIC GAUGES
All gauges on the AP Body clusters are the mag-
netic type gauges. When the ignition switch is in the
OFF position each gauge, except for the voltmeter
and tachometer will show a reading. However, the
readings are only accurate when the ignition switch
is in the ON position.
TACHOMETER DRIVE MODULE
The tachometer drive module is an electronic mod-
ule used to drive the magnetic tachometer in the
high line cluster. This module is located on top of the instrument
cluster.
ELECTRONIC DIGITAL CLOCK
The electronic digital clock is in the radio. The
clock and radio each use the display panel built into
the radio. A digital readout indicates the time in
hours and minutes whenever the ignition switch is in
the ON or ACC position. When the ignition switch is in the OFF position, or
when the radio frequency is being displayed, time
keeping is accurately maintained. The procedure for setting the clock varies slightly
with each radio. The correct procedure is described
under the individual radio operating instructions re-
fer to the Sound Systems Manual supplied with the
vehicle.
WARNING LAMPS AND INDICATOR LIGHTS
The instrument cluster has warning and indicators
lamps for eight different systems:
² Low oil pressure
² Brake warning
² Seat belt warning
² Malfunction indicator (check engine) lamp
² Air Bag
² High beam indicator
² Right and left turn signals.
² Anti-lock (ABS)
CLUSTER AND GAUGE SERVICE AND TESTING
CAUTION: Disconnect the negative battery cable
before servicing the instrument panel. When power
is required for test purposes, reconnect battery ca-
ble for test only. Disconnect the negative battery
cable after test and before continuing service pro-
cedures.
SENDING UNIT TEST
Check for a defective sending unit or wiring, when
a problem occurs with a cluster gauge. Do this before
disassembling the cluster. (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 fuel or temperature
gauge to read at or above maximum.
Fig. 1 Instrument Cluster With Tachometer
Fig. 2 Instrument Cluster Without Tachometer
8E - 58 INSTRUMENT PANEL AND GAUGES Ä

FUEL TANK SENDING UNIT TEST
Refer to Group 14, Fuel for test procedures.
LOW OIL PRESSURE WARNING LAMP TEST
The low oil pressure warning lamp will illuminate
when the ignition key is turned to the ON position
without engine running. The lamp also illuminates
should the engine oil pressure drop below a safe oil
pressure level. 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
unit, located at the front of the engine (Fig. 3). If the
wire at the connector checks good, pull connector
loose from the switch and with a jumper wire ground
connector to the engine. With the ignition key turned
to the ON position check the warning lamp. If lamp
still fails to light, inspect for a burned out lamp or
disconnected socket in the cluster.
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 (Fig. 4).
(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 continuity. Start
the engine. 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 no continuity. 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 8M, Re-
straint Systems.
AIR BAG WARNING SYSTEM
For testing of this system refer to Group 8M, Re-
straint Systems.
MALFUNCTION INDICATOR (CHECK ENGINE) SYSTEM
For testing of this system using DRB II, refer to
the Body Powertrain Diagnostic Procedures.
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. Refer to Brake system warning Lamp Diagno-
sis (Fig. 5). To test system turn ignition key ON and apply
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. To test service brake warning system, raise vehicle
on a hoist and open a wheel cylinder bleeder while a
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 compart-
ment below master cylinder (Fig. 6).
CAUTION: If wheel cylinder bleeder was opened
check master cylinder fluid level.
Fig. 3 Combination Oil Sending Unit
Fig. 4 Combination Oil Sending Unit Test
Ä INSTRUMENT PANEL AND GAUGES 8E - 59