brake CHEVROLET DYNASTY 1993 Service Manual

Fig. 11 Body Routing of Rear Speed Sensor Wiring
Fig. 10 Rear Wheel Speed Sensor Routing at Trailing Arm
Ä ANTILOCK 4 BRAKE SYSTEM 5 - 45

SPECIFICATIONS
SPECIFICATIONS METRIC
BRAKE ACTUATION SYSTEM
TIGHTENING REFERENCE
5 - 46 ANTILOCK 4 BRAKE SYSTEM Ä

CLUTCH PEDAL POSITION SWITCH
The clutch pedal position switch functions as a
safety interlock device. It prevents possible engine
cranking with the clutch engaged. The clutch pedal position switch is wired in series
between the starter relay coil and the ignition
switch. The clutch pedal position switch is mounted to a
bracket located next to the clutch pedal. The switch
is held in place by four plastic wing tabs. The clutch pedal position switch has an adjustable
striker plate. The striker plate is located on the left
side of the clutch pedal (Fig. 3).
DIAGNOSIS
Disconnect clutch pedal position switch harness
from instrument panel wiring harness. Using a ohm
meter, check for continuity between the two termi-
nals in the connector on the switch harness. There
should be no continuity between the terminals when
the switch is in its neutral (fully extended) position.
When the switch is depressed more than 1.25 mm
(0.050) the ohm meter should show continuity. If all ohm meter readings are correct and the
switch does not operate correctly, adjustment is re-
quired. Refer to Switch Adjustment Procedure to ad-
just switch.
REMOVAL
(1) Disconnect electrical harness to switch connec-
tor. (2) Depress wing tabs on switch and push switch out
of mounting bracket. Then slide wires through slot in
bracket.
INSTALLATION
(1) Slide switch wires through slot in switch bracket.
(2) Line up switch tab with slot in switch bracket
and push switch into position. Do not pull on the switch
wires to seat switch into bracket, switch damage may
occur. (3) After installation, the switch must be adjusted
and checked for proper operation. Refer to Switch
Adjustment Procedure.
ADJUSTMENT PROCEDURE
When performing switch adjustment, the floor mat
should be removed before beginning adjustment proce-
dures. (1) Set the park brake.
(2) Disconnect clutch cable at the transaxle end of
the cable. (3) Depress clutch pedal, loosen adjusting nut and
slide the striker plate forward to fully compress the
clutch pedal position switch plunger. (4) Tighten adjusting nut to 12 N Im (105 in. lbs.).
(5) Reconnect clutch cable.
The clutch pedal position switch is now ad-
justed. A final check is required to insure that the
switch is ``made'' below the clutch release point. (1) With the park brake set and the vehicle IN
NEUTRAL turn the key to the start position. The
vehicle should not crank. If the vehicle cranks do
not continue with this test. Recheck the switch and
switch adjustment to determine the cause. If the ve-
hicle does not crank proceed to step 2. (2) With the park brake set and the vehicle IN
GEAR turn the key to the start position.
WARNING: BEFORE PERFORMING STEP THREE BE
SURE THAT THE AREA IN FRONT OF THE VEHICLE
IS CLEAR OF OBSTRUCTIONS AND PEOPLE. VE-
HICLE MAY MOVE WHEN PERFORMING THIS TEST.
(3) Slowly depress the clutch pedal and feel for any
vehicle motion when the starter is energized. If there is
no motion the switch is properly adjusted. If motion is
felt, repeat the adjustment procedure.
Fig. 3 Clutch Pedal Position Switch and Components
6 - 4 MANUAL TRANSAXLE CLUTCH Ä

² VEHICLES WITH DIRECT IGNITION SYSTEM:
Disconnect the ignition coils electrical connector (Fig.
7). (3) Verify that all lights and accessories are OFF,
and the transmission shift selector is in PARK or
manual in NEUTRAL. Set parking brake. (4) Rotate and hold the ignition switch in the
START position. Observe the volt-ampere tester (Fig.
8). ²
If voltage reads above 9.6 volts, and amperage
draw reads above 250 amps, go to the starter feed
circuit resistance test.
² If voltage reads 12.4 volts or greater and amperage
reads 0 to 10 amps, go to starter control circuit test.
CAUTION: Do not overheat the starter motor or
draw the battery voltage below 9.6 volts during
cranking operations.
(5) After the starting system problems have been
corrected, verify the battery state of charge and
charge battery if necessary. Disconnect all testing
equipment and connect ignition coil cable or ignition
coil connector. Start the vehicle several times to as-
sure the problem was corrected.
Fig. 4 Volt Ampere Tester
Fig. 5 Volt-Ampere Tester Connections
Fig. 6 Ground Ignition Coil Cable
Fig. 7 Ignition Coils Electrical Connection
Fig. 8 Starter Draw Tests
Ä BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 13

STARTER CONTROL CIRCUIT TESTS
The starter control circuit has:
² Starter solenoid
² Starter relay (Fig. 2)
² Neutral starting and back-up switch with auto-
matic transmissions
² Clutch pedal mounted starter interlock switch
with manual transmissions
² Ignition switch
² Battery
² All related wiring and connections
CAUTION: Before performing any starter tests, the
ignition system must be disabled.
² VEHICLES EQUIPPED WITH A CONVEN-
TIONAL DISTRIBUTOR: Disconnect coil wire from
distributor cap center tower. Secure wire to a good
ground to prevent engine from starting (Fig. 6).
² VEHICLES EQUIPPED WITH DIRECT IGNI-
TION SYSTEM: Unplug the coils electrical connector
(Fig. 7).
STARTER SOLENOID TEST
WARNING: CHECK TO ENSURE THAT THE TRANS-
MISSION IS IN PARK OR NEUTRAL WITH THE
PARKING BRAKE APPLIED
(1) Verify battery condition. Battery must be in
good condition with a full charge before performing
any starter tests. Refer to Battery Tests. (2) Perform this starter solenoid test BEFORE per-
forming the starter relay test. (3) Raise the vehicle.
(4) Perform a visual inspection of the starter/
starter solenoid for corrosion, loose connections or
faulty wiring. (5) Lower the vehicle.
(6) Locate the starter relay as follows:
² On AC, AG, AJ and AY Bodies the relay is located
in the Power Distribution Center. This Center is mounted near the front of the left front strut tower
(Fig. 13). The position of the starter relay within this
Center will be shown on the Center cover.
² On AA/AP Bodies the relay is located on the front
of the left front strut tower (Fig. 14).
(7) Remove the starter relay from the connector.
(8) Connect a remote starter switch or a jumper
wire between the battery positive post and terminal
87 on the starter relay connector. To decide the
starter relay terminal numbers, refer to the Starter
Relay Tests.
² If engine now cranks, starter/starter solenoid is
good. Go to the starter relay test.
² If engine does not crank with this test, or solenoid
chatters, check wiring and connectors from starter
Fig. 12 Test Positive Battery Cable Resistance
Fig. 13 Starter Relay LocationÐAC, AG, AJ, and AY Bodies
Fig. 14 Starter Relay LocationÐAA/AP Body
Ä BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 15

relay to starter solenoid for loose or corroded connec-
tions. Particularly at starter terminals.
² Repeat test. If engine still fails to crank properly,
trouble is within starter or starter mounted solenoid,
and it must be removed for repairs. Refer to Group
8B, Battery/Starter/Generator Service, Starter re-
placement.
STARTER RELAY TEST
WARNING: CHECK TO ENSURE THAT THE TRANS-
MISSION IS IN PARK OR NEUTRAL WITH THE
PARKING BRAKE APPLIED
(1) Verify battery condition. Battery must be in
good condition with a full charge before performing
any starter tests. Refer to Battery Tests. (2) Perform the preceding starter solenoid tests
BEFORE performing starter relay tests. Refer to
Starter Solenoid Test. (3) Locate and remove the starter relay. For
starter relay locations, refer to Starter Solenoid Test
(Fig. 13 or 14). (4) After the starter relay has been located and re-
moved, refer to Starter Relay Tests (Fig. 15).
NEUTRAL STARTING AND BACK-UP SWITCH
AUTOMATIC TRANSMISSION ONLY
For electrical diagnostics, when checking starter
circuits, refer to Starter Relay Tests (Fig. 15). For replacement of switch, refer to Group 21, Tran-
saxle, Neutral Starting and Switch Replacement.
STARTER INTERLOCK SWITCHÐCLUTCH PEDAL MOUNTED
MANUAL TRANSMISSION ONLY
For electrical diagnostics, refer to the Starter Relay
Tests. For replacement and/or adjustment of the switch,
refer to Group 6, Manual Transaxle Clutch, Manual
Transaxle Starter Interlock Switch.
IGNITION SWITCH TEST
After testing the starter solenoid and relay, test ig-
nition switch and wiring. Refer to Group 8D, Ignition
Systems, or the Front Wheel Drive Car Wiring Dia-
grams Service Manual. Check all wiring for opens or
shorts, and all connectors for being loose or corroded.
BENCH TESTING STARTER SOLENOID
(1) Disconnect field coil wire from field coil termi-
nal (Fig. 16 or 17). (2) Check for continuity between solenoid terminal
and field coil terminal with a continuity tester. Con-
tinuity should be detected (Fig. 18 or 19). (3) Check for continuity between solenoid terminal
and solenoid housing (Fig. 20 or 21). Continuity
should be detected. If continuity is detected, solenoid
is good. (4) If continuity is not detected in either test, sole-
noid has an open circuit and is defective. If equipped
with:
² BOSCH STARTER: Replace the solenoid.
² NIPPONDENSO STARTER: Replace the starter
assembly.
8A - 16 BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 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

dition exists. These messages are displayed on the
center of the instrument panel.For complete EVIC operating instructions, 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
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.
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 sec-
onds.
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. Press-
ing the buttons a second time will restore the dis-
play.
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 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. 3.
The Engine Compartment Node is a microcomputer
controlled unit which, informs the EVIC 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 via the CCD
bus of the following warning messages:
² Engine temperature high
² Voltage improper
8C - 14 OVERHEAD CONSOLE Ä

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