1993 CHEVROLET DYNASTY wiring

SENDING UNIT TEST
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.
LOW OIL PRESSURE/CHECK GAUGES WARNING LAMP TEST
The low oil pressure/check gauges warning lamp
will illuminate when the ignition key is turned to
the ON position without starting the vehicle. In the cluster assembly without tachometer, the
low oil pressure lamp will illuminate if the engine oil
pressure drops below a safe oil pressure level. In the cluster assembly with tachometer, the Check
Gauges warning lamp illuminates when there is a
problem in oil pressure level, high engine tempera-
ture or 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
unit, which is located at the front of the engine (Figs.
5 and 6). If the wire at the connector checks good,
pull connector loose from the switch terminal and
with a jumper wire ground connector to the engine
(Fig. 7). With the ignition key turned to the ON po-
sition check the warning lamp. If lamp still fails to
light, inspect for a burned out lamp or disconnected
socket in the cluster.
COMBINATION OIL UNIT TEST
The combination oil unit has two functions:
(1) The normal closed circuit keeps the oil pressure
warning/check gauges lamp on until there is oil pres-
sure (Fig. 7). (2) The sending unit provides a resistance that
varies with oil pressure. (3) To test the normally closed oil lamp circuit, dis-
connect 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. (4) If there is oil pressure, the ohmmeter should
read an open circuit. (5) To test the sending unit, measure the resis-
tance between the sending unit terminal and the
metal housing. The ohmmeter should read open.
Start the engine. (6) The ohmmeter should read between 30 to 55
ohms, depending on engine speed, oil temperature,
and oil viscosity. (7) If the above results are not obtained, replace
the switch.
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 orFig. 5 Combination Oil Unit (2.5L)
Fig. 6 Combination Oil Unit (3.0L)
Fig. 7 Combination Oil Unit Test
Ä INSTRUMENT PANEL AND GAUGES 8E - 3

(b) Place gear shift lever in neutral or park.
(c) Remove guide tube from behind fuse block
and disconnect cable eyelet from column actuating
arm. (d) Release lock bar on column insert, squeeze
legs together and remove from column (Fig. 14). (e) Secure insert and cable guide out of the way.
(4) Remove the rear window defogger bezel and ra-
dio bezel. (5) Remove the upper steering column cover. (6) Remove the four screws attaching cluster hous-
ing to the base panel. (7) Pull cluster rearward, reach behind cluster and
disconnect the two wiring harnesses. (8) Remove cluster assembly.
INSTALLATION (1) Connect wiring harnesses.
(2) Position cluster and secure to base panel with
four screws. (3) On column shift vehicles (Fig. 12 through 15):
Fig. 15 Transmission Range Indicator Step 4
Fig. 16 Instrument Panel Bezels
Fig. 14 Transmission Range Indicator Step 3
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(2) With the ignition key ON, check for ignition
voltage at ignition pin of gauge. Check for ground at
ground pin of gauge. Refer to the individual gauge
circuit test for proper pin. (a) If voltage at pin, replace gauge.
(b) If no voltage or ground at gauge pins, check
for ignition voltage and ground at cluster harness
connectors. (c) If no voltage or ground, repair as necessary.
Refer to 8W, Wiring Diagrams. (d) If there is voltage or ground, check cluster for
distorted terminals. If terminals are OK, replace
printed circuit board.
Fig. 19 Voltmeter PinsÐWith Tachometer
Fig. 20 Voltmeter PinsÐWithout Tachometer
Fig. 21 Temperature Gauge PinsÐWith Tachometer
Fig. 22 Temperature Gauge PinsÐWithout Tachometer
Fig. 23 Oil Pressure Gauge PinsÐWith Tachometer
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(4) Check cavity H of the black connector for con-
tinuity to ground. (5) Check for tachometer signal from the power-
train control module by connecting an AC DIGITAL
VOLTMETER to cavity B of the instrument cluster
black connector and ground. A reading of at least 1.0
volt should be present with the engine running (Fig.
26).
(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 B, check
for continuity between cavity B and pin 43 of the
powertrain control module connector. (a) If continuity is OK, between cavity B 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 AND FUEL GAUGE ASSEMBLY REPLACEMENT
(1) Remove cluster, radio and rear window defog-
ger bezels and mask/lens assembly. (2) Remove tachometer.
(3) Remove screw attaching gauge assembly to
cluster. (4) Pull rearward to remove gauge assembly.
(5) For installation reverse above procedures.
OIL PRESSURE AND TEMPERATURE GAUGEASSEMBLY REPLACEMENT
(1) Remove cluster, radio and rear window defog-
ger bezels and mask/lens. (2) Remove speedometer. (3) Remove screw attaching gauge assembly to
cluster. (4) Pull rearward to remove gauge assembly.
(5) For installation reverse above procedures.
FUEL GAUGE REPLACEMENT
(1) Remove cluster, radio and rear window defog-
ger bezels and mask/lens. (2) Remove screws attaching fuel gauge to cluster
housing. (3) Pull fuel gauge rearward to remove.
(4) For installation reverse above procedures.
VOLTMETER GAUGE REPLACEMENT
(1) Remove cluster bezel and mask.
(2) Remove fuel gauge.
(3) Remove screws attaching voltmeter assembly to
cluster. (4) Pull rearward to remove gauge assembly.
(5) For installation reverse above procedures.
TEMPERATURE GAUGE ASSEMBLY REPLACEMENT
(1) Remove cluster bezel and mask.
(2) Remove speedometer.
(3) Remove screws attaching gauge assembly to
cluster. (4) Pull rearward to remove gauge assembly.
(5) For installation reverse above procedures.
SPEEDOMETER SYSTEM
AA body 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.
27 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.
SPEEDOMETER-ODOMETER ASSEMBLY REPLACEMENT
(1) Remove cluster bezel and mask.
(2) Remove two screws attaching the speedometer
and odometer assembly to the cluster housing. (3) Pull speedometer rearward to disengage from
gauge pins. (4) For installation reverse above procedures.
Fig. 26 Powertrain Control Module Pin Location
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CONDITION: SPEEDOMETER AND ODOMETER ARE INOPERATIVE OR OPERATESINTERMITTENTLY
PROCEDURE
Check for defective vehicle speed sensor wiring.
CONDITION: OIL GAUGE, FUEL GAUGE, TEMPERATURE GAUGE, OR VOLTAGE GAUGEINOPERATIVE
PROCEDURE
Check for defective sending unit or wiring: (a) Sending units and wiring can be checked by
grounding the connector leads, at the sending unit,
in the vehicle. (b) With the ignition in the ON position, a
grounded input will cause the oil, fuel, or temper-
ature gauge to read maximum.
CONDITION: CLUSTER DISPLAY DOES NOT DIM WHEN HEADLAMP SWITCH ISACTIVATED AND RHEOSTAT ROTATED
PROCEDURE
(1) Check fuses in headlamp circuit.
(2) Check for loose connections or defective wiring
from headlamp switch to the cluster. (3) Check for defective headlamp switch.
(4) The electronic instrument cluster requires both
a marker feed and illumination feed to operate cor-
rectly.
SWITCH AND PANEL COMPONENT SERVICE
HEADLAMP/FOG LAMP SWITCH REPLACEMENT
(1) Remove cluster bezel (Fig. 40).
(2) Remove three screws securing headlamp switch
mounting plate to base panel (Fig. 41). (3) Pull headlamp/fog lamp switch mounting plate
rearward. Disconnect wiring connectors from head-
lamp switch and fog lamp switch pigtail (Fig. 42). (4) Remove knob and stem by depressing button on
bottom of the switch (Fig. 43). (5) Snap-out escutcheon.
(6) Remove fog lamp switch from escutcheon.
(7) Remove nut that attaches headlamp switch to
mounting plate (Fig. 44). (8) For installation reverse above procedures.
FOG LAMP SWITCH TEST
(1) Remove the fog lamp switch from mounting lo-
cation. (2) Disconnect the wiring harness from the switch
pigtail. (3) Using a Ohmmeter, test for continuity between
the terminals of the switch pigtail (Fig. 45). (4) If not OK, replace switch.
LOWER STEERING COLUMN COVERREPLACEMENT
(1) Disconnect park brake release rod from park
brake. (2) Remove fuse box access door and remove screw
from lower column cover (Fig. 46). (3) Remove screws from lower cover, four across
the top and two on bottom. (4) Remove lower steering column cover.
(5) For installation reverse above procedures.
LEFT LOWER INSTRUMENT PANEL SILENCER REPLACEMENT
(1) Remove screws from front of silencer (Fig. 47).
(2) Remove push nut.
(3) Remove silencer.
(4) For installation reverse above procedures.
RIGHT LOWER INSTRUMENT PANEL SILENCER REPLACEMENT
(1) On floor shift vehicles, remove console assem-
bly and center brace bracket. (2) On column shift vehicles, remove center brace
bracket. (3) Remove screws from front of silencer (Fig. 47).
(4) Remove three push nuts from rear of silencer.
(5) Remove lower right silencer.
(6) For installation reverse above procedures.
GLOVE BOX ASSEMBLY REPLACEMENT
(1) Disconnect battery negative cable and isolate
or remove fuse #2 prior to removing switch or wires
may short to ground. (2) Open glove box door and disconnect check
strap. (3) Remove glove box light and switch by squeez-
ing retaining tabs from behind switch mount and
slide rearward. Disconnect wiring connectors. (4) Remove 11 screws from glove box assembly
(Fig. 48). (5) Remove glove box assembly.
Fig. 36 Electronic Cluster
Ä INSTRUMENT PANEL AND GAUGES 8E - 15

(6) For installation reverse above procedures and
check operation of glove box door and adjust latch as
necessary.
GLOVE BOX LAMP AND SWITCH REPLACEMENT
(1) Disconnect battery negative cable and isolate
or remove fuse #2 prior to removing switch or wires
may short to ground. (2) Open glove box door. The lamp can be removed
without removing switch (3) Remove switch by squeezing retaining tabs
from behind switch mount and slide rearward. Dis-
connect wiring connectors. (4) Remove lamp and switch.
(5) For installation reverse above procedures.FOG LAMP RELAY REPLACEMENT
(1) Disconnect battery negative cable and isolate
or remove fuse #2 prior to removing switch or wires
may short to ground.
ART: 938e-92 ; SIZE (6) = 4-1/2h x 7-1/4w
Fig. 39 Cluster Connectors
Fig. 40 Cluster BezelFig. 41 Headlamp Switch Mounting Screws
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(2) Remove glove box assembly (Fig. 49). Refer to
Glove Box Assembly Replacement. (3) Remove screw from relay.
(4) Disconnect wiring.
(5) Remove relay. (6) For installation reverse above procedures.
REAR WINDOW DEFOGGER SWITCH
REPLACEMENT
(1) Remove left bezel by pulling straight back.
(2) Press tabs and pull switch rearward.
(3) Disconnect wiring and remove switch.
(4) For installation reverse above procedures.
INSTRUMENT PANEL CENTER BEZELREPLACEMENT
(1) Pull bezel straight back disengaging five clips.
(2) Disconnect ash receiver lamp and wiring from
bezel. (3) For installation reverse above procedures.
ASH RECEIVER/CUP HOLDER REPLACEMENT
(1) Remove center bezel. Disconnect ash receiver
lamp socket. (2) Remove four screws from center module and re-
move module.
Fig. 42 Headlamp Switch Wiring Connectors
Fig. 43 Headlamp Switch Knob and Stem
Fig. 44 Headlamp Switch Mounting Nut
Fig. 45 Fog Lamp Switch Test
Fig. 46 Lower Steering Column Cover
Ä INSTRUMENT PANEL AND GAUGES 8E - 19

(3) Remove four screws from ash receiver/cup
holder housing. (4) For installation reverse above procedures.
AIR CONDITIONING CONTROLREPLACEMENT
(1) Disconnect battery negative cable and isolate
or remove fuse #2 prior to removing switch or wires
may short to ground. (2) Remove center bezel. Disconnect ash receiver
lamp socket. (3) Remove glove box assembly. Refer to Glove Box
Assembly Replacement. (4) Reach through glove box opening and discon-
nect vacuum lines. (5) Remove two control mounting screws (Fig. 50).
(6) Slide control rearward, disconnect cable, and
electrical wiring. (7) Remove unit.
(8) For installation reverse above procedures.
CIGAR LIGHTER ASSEMBLY REPLACEMENT
(1) Remove center bezel. Disconnect ash receiver
lamp socket. (2) Remove two screws from bezel of the lighter as-
sembly. (3) Pull assembly rearward and disconnect wiring.
(4) For installation reverse above procedures.
TRAVELER/MESSAGE CENTER REPLACEMENT
(1) Remove cluster bezel.
(2) Remove four mounting screws.
(3) Pull unit rearward and disconnect wiring.
(4) For installation reverse above procedures.
INSTRUMENT PANEL
INSTRUMENT PANEL TOP COVER REPLACEMENT
(1) Lift up rearward edge of instrument panel top
cover. (2) Pull panel rearward to remove.
(3) To install: position top cover and snap into
place, pull rearward for proper fit.
INSTRUMENT PANEL REPLACEMENT
CAUTION: Disconnect negative battery cable, in en-
gine compartment, before servicing instrument
panel.
(1) Disconnect battery negative cable and isolate
or remove fuse #2 prior to removing switch or wires
may short to ground. (2) Remove left and right A-pillar trim.
(3) Remove left and right cowl side trim.
(4) Remove glove box assembly. Refer to Glove Box
Assembly Replacement. (5) Remove four relays above glove box assembly.
(6) Reach through glove box opening and discon-
nect A/C control vacuum lines, radio noise suppressor
wires, and blower motor/cycling switch wires. (7) Remove hood release handle.
(8) Remove lower steering column cover.
(9) Remove lower left instrument panel silencer
and reinforcement. (10) Remove instrument panel center bezel.
(11) Remove floor console. Refer to Group 23,
Body. (12) Remove radio, A/C control, cigar lighter, and
message center/traveler. (13) Disconnect demister hoses.
(14) Remove instrument panel top cover (Fig. 51).
(15) Disconnect battery to assure no air bag sys-
tem fault codes are stored. (16) Remove cluster refer to Cluster Assembly.
(17) Remove radio and rear window defogger be-
zels. (18) Lower steering column.
(19) Loosen instrument panel pivot bolts.
(20) Remove screws which attach instrument panel
to windshield fence line. (21) Allow panel to roll down slightly and discon-
nect remaining electrical connections. (22) With the aid of a helper remove panel pivot
bolts and remove panel from vehicle. (23) For installation reverse above procedures.
INTERIOR LAMP REPLACEMENT
The dome, overhead console and door lamps, if
equipped operate when the doors are open or head-
lamp switch is placed in courtesy position. The front
header reading lamp operates only when the lamp
push buttons are ON.
DOME LAMP
Pry either the forward or rearward edge of the lens
away from the bezel and replace lamp.
FRONT HEADER READING LAMP
Pull lamp from headliner. Disconnect wiring and
replace lamp.
Fig. 50 A/C Control
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