brakes VOLKSWAGEN CORRADO 1993 Owner's Manual
[x] Cancel search | Manufacturer: VOLKSWAGEN, Model Year: 1993, Model line: CORRADO, Model: VOLKSWAGEN CORRADO 1993Pages: 920, PDF Size: 6.92 MB
Page 286 of 920
* SYMPTOM CHECK LIST *
Article Text (p. 9)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:45PMFig. 7: Brakes, Steering, & Suspension
Page 409 of 920
ANTI-LOCK BRAKE SAFETY PRECAUTIONS
Article Text
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:57PM
ARTICLE BEGINNING
GENERAL INFORMATION
Anti-Lock Brake Safety Precautions
* PLEASE READ THIS FIRST *
This article is intended for general information purposes
only. This information may not apply to all makes and models. If
vehicle is equipped with Anti-Lock Brake System (ABS), refer to
appropriate ANTI-LOCK BRAKE SYSTEM article in the BRAKES section for
description, operation, depressurizing, testing, system bleeding,
trouble shooting and servicing of specific system.
WARNING: Failure to depressurize ABS could lead to physical injury.
ANTI-LOCK BRAKE SAFETY PRECAUTIONS
WARNING: Failure to depressurize ABS could lead to physical injury.
* NEVER open a bleeder valve or loosen a hydraulic line
while ABS is pressurized.
* NEVER disconnect or reconnect any electrical connectors
while ignition is on. Damage to ABS control unit may result.
* DO NOT attempt to bleed hyudarulic system without first
referring to the appropriate ANTI-LOCK BRAKE SYSTEM article
in the BRAKES section.
* Only use specially designed brake hoses/lines on ABS equipped
vehicles.
* DO NOT tap on speed sensor components (sensor, sensor rings).
Sensor rings must be pressed into hubs, NOT hammered into
hubs. Striking these components can cause demagnetization or
a loss of polarization, affecting the accuracy of the speed
signal returning to the ABS control unit.
* DO NOT mix tire sizes. Increasing the width, as long as tires
remain close to the original diameter, is acceptable. Rolling
diameter must be identical for all 4 tires. Some
manufacturers recommend tires of the same brand, style and
type. Failure to follow this precaution may cause inaccurate
wheel speed readings.
* DO NOT contaminate speed sensor components with grease. Only
use recommended coating, when system calls for an
anti-corrosion coating.
* When speed sensor components have been removed, ALWAYS check
sensor-to-ring air gaps when applicable. These specifications
can be found in each appropriate article.
* ONLY use rocommended brake fluids. DO NOT use silicone brake
fluids in an ABS equipped vehicle.
* When instlling transmittion devices (CB's, telephones, etc.)
on ABS equipped vehicles, DO NOT locate the antenna near the
ABS control unit (or any control unit).
Page 411 of 920
ANTI-LOCK BRAKE SYSTEM
Article Text
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:57PM
ARTICLE BEGINNING
1993 BRAKES
Volkswagen Anti-Lock
Corrado SLC
ANTI-LOCK BRAKE SAFETY PRECAUTIONS
* NEVER open a bleeder valve or loosen a hydraulic line while
ABS is pressurized
* NEVER disconnect or reconnect any electrical connectors while
ignition is on. Damage to ABS control unit may result.
* DO NOT attempt to bleed hydraulic system without first
referring to the appropriate article.
* Only use specially designed brake hoses/lines on ABS-equipped
vehicles.
* DO NOT tap on speed sensor components (sensor, sensor rings).
Speed rings must be pressed, NOT hammered into hubs. Striking
these components can cause demagnetization or a loss of
polarization, affecting the accuracy of the speed signal
returning to the ABS control unit.
* DO NOT mix tire sizes. Increasing the width, as long as tires
remain close to the original diameter, is acceptable. Rolling
diameter must be identical for all 4 tires. Some
manufacturers recommend tires of the same brand, style and
type. Failure to follow this precaution may cause inaccurate
wheel speed readings.
* DO NOT contaminate speed sensor components with grease. Only
use recommended anti-corrosion coating.
* When speed sensor components have been removed, ALWAYS check
sensor-to-ring air gaps when applicable. These specifications
can be found in each appropriate article.
* ONLY use recommended brake fluids. DO NOT use silicone brake
fluids in an ABS-equipped vehicle.
* When installing transmitting devices (CB's, telephones, etc.)
on ABS-equipped vehicles, DO NOT locate the antenna near the
ABS control unit (or any control unit).
* Disconnect all on-board computers, when using electric
welding equipment.
* DO NOT expose the ABS control unit to prolonged periods of
high heat (185øF/85øC for 2 hours is generally considered a
maximum limit).
DESCRIPTION
A Teves Anti-Lock Brake System (ABS) is used. See Fig. 1.
This system reduces the chance of wheel lock-up during heavy braking.
The system consists of 4 wheel speed sensors, Electronic Control Unit
(ECU), hydraulic modulator/pump and solenoid valves, ANTILOCK and
BRAKE warning lights. There are 2 relays located at fuse/relay panel,
Page 412 of 920
ANTI-LOCK BRAKE SYSTEM
Article Text (p. 2)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:57PM
to protect the hydraulic modulator and ECU.
NOTE: For more brake system information, see BRAKE SYSTEM
article in the BRAKES section.
OPERATION
When pressure is applied to brake pedal, ECU monitors input
signals from each wheel speed sensor. If ECU measures a rate of
reduction greater than what is programmed in ECU, the ECU will output
a signal to appropriate solenoid valve. Each solenoid valve allows
hydraulic pressure to increase or decrease to the appropriate wheel
cylinder.
If a system failure occurs, ANTILOCK warning light, located
on instrument panel, will come on. System will be deactivated, but
conventional brake system will still operate. If brake fluid level
drops too low, BRAKE warning light, located on instrument panel, will
come on.
CAUTION: See ANTI-LOCK BRAKE SAFETY PRECAUTIONS in this article.
CAUTION: The ABS system is under extremely high pressure. Depressurize
the brake system before loosening or removing any hydraulic
component.
DEPRESSURIZING BRAKE SYSTEM
Turn ignition off. Depress and release brake pedal 25-35
times, or until there is a noticeable increase in the effort to
depress the brake pedal. DO NOT turn ignition on until all hydraulic
lines and components are fully tighten.
BLEEDING BRAKE SYSTEM
FRONT BRAKES
Depressurize brake system. See DEPRESSURIZING BRAKE SYSTEM.
Connect a container with hose to left front bleeder screw. Have
assistant depress and release brake pedal a few times. Holding brake
pedal down, open bleeder screw and allow fluid to enter container.
Close bleeder screw and then release brake pedal. Continue this method
until no air is present in fluid. Check master cylinder fluid level to
make sure it does not go below minimum level mark. Use same procedure
for right front brake.
REAR BRAKES
CAUTION: When bleeding rear brakes, accumulator pressure (about 3100
psi) is used to assist in procedure. Use eye protection when
performing this procedure. DO NOT allow pump to run longer
than 2 minutes. See ANTI-LOCK BRAKE SAFETY PRECAUTIONS in
Page 415 of 920
ANTI-LOCK BRAKE SYSTEM
Article Text (p. 5)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:57PM
fuse. If fuse is faulty, replace and retest. If fuse is okay, check
wiring. If wiring is faulty, repair and retest. If wiring is okay,
replace relay and retest.
Brakelight Switch
Turn ignition on. Apply brakes. Check for 12 volts between
terminals No. 12 and 1. If 12 volts are present, brakelight switch is
okay. If 12 volts are not present, check fuse, brakelight switch and
Black/Red wire from brakelight switch to ECU.
Hydraulic Modulator/Pump Relay Voltage Test
1) Turn ignition off. Unplug hydraulic modulator/pump
connector. Depress brake pedal 25 times. Turn ignition on. Using a
voltmeter, measure voltage between ECU connector terminals No. 1 and
32. See Fig. 2. If voltage is 10 volts or more, go to RIGHT REAR WHEEL
SPEED SENSOR VOLTAGE TEST under SYSTEM TESTING.
2) If voltage is less than 10 volts, check hydraulic
modulator/pump fuse. If fuse is okay, check wiring between ECU
connector terminal No. 32 and hydraulic modulator/pump connector
terminal No. 1 (large gauge Red/Black wire). See Figs. 2 and 4. If
wiring is not okay, repair wiring, and retest. If wiring is okay,
replace relay, and retest.
Right Rear Wheel Speed Sensor Voltage Test
Connect an AC voltmeter between ECU connector terminals No. 4
and 22. See Fig. 2. Rotate right rear wheel at one revolution per
second. Measure voltage with wheel rotating. If voltage is 0.075 volt
or more, go to next test. If voltage is less than 0.075 volt, check
wheel speed sensor and/or toothed ring for damage, wear and proper
installation. If damage or wear is found, replace faulty component and
retest. If components are not properly installed, reposition and
retest. If components are okay, replace wheel speed sensor and retest.
Left Rear Wheel Speed Sensor Voltage Test
Connect an AC voltmeter between ECU connector terminals No. 6
and 24. See Fig. 2. Rotate left rear wheel at one revolution per
second. Measure voltage with wheel rotating. If voltage is 0.075 volt
or more, go to next test. If voltage is less than 0.075 volt, check
wheel speed sensor and/or toothed ring for damage, wear and proper
installation. If damage or wear is found, replace faulty component and
retest. If components are not properly installed, reposition and
retest. If components are okay, replace wheel speed sensor and retest.
Right Front Wheel Speed Sensor Voltage Test
Connect an AC voltmeter between ECU connector terminals No. 7
and 25. See Fig. 2. Rotate right front wheel at one revolution per
second. Measure voltage with wheel rotating. If voltage is 0.075 volt
or more, go to next test. If voltage is less than 0.075 volt, check
wheel speed sensor and/or toothed ring for damage, wear and improper
installation. If damage or wear is found, replace faulty component,
and retest. If components are improperly installed, reposition
component, and retest. If components are okay, replace wheel speed
Page 432 of 920
BRAKE SYSTEM
Article Text
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:57PM
ARTICLE BEGINNING
1992-93 BRAKES
Volkswagen Disc & Drum
Corrado SLC
DESCRIPTION
All models are equipped with front disc brakes. Rear brakes
are either disc or drum. Parking brake acts on rear brakes and is
cable-actuated. All models use pressure regulator between front and
rear brake circuits to avoid rear wheel lock-up during hard braking.
A vacuum power-assist servo is used to ease brake pedal
application. A vacuum check valve, located in vacuum supply hose,
prevents vacuum leakdown when engine is off.
SERVICING
Manufacturer recommends replacing brake fluid every 2 years.
BLEEDING BRAKE SYSTEM
CAUTION: Ensure fluid level in master cylinder is adequate at all
times during bleeding procedure. Use only DOT 4 brake fluid.
DO NOT use DOT 5 silicone brake fluid.
BLEEDING PROCEDURES
NOTE: Manufacturer recommends bleeding brake system using Pressure
Bleeder (US 1116). If a pressure bleeder is not available,
use standard bleeding procedure.
1) Exhaust vacuum reserve from power unit by depressing brake
pedal several times. On ABS-equipped vehicles, depress brake pedal at
least 20 times to relieve system pressure.
2) On all vehicles, fill master cylinder with clean brake
fluid. If master cylinder was replaced, bleed master cylinder before
bleeding wheel calipers. Connect bleeder hose to appropriate caliper
bleeder valve. See BRAKE BLEEDING SEQUENCE table.
BRAKE BLEEDING SEQUENCE TABLEÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄApplication (1) Sequence
Corrado SLC .................. Either Front Caliper First,
Either Rear Caliper First
(1) - Push lever of pressure regulator in direction of rear
axle when bleeding rear brakes.
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Page 433 of 920
BRAKE SYSTEM
Article Text (p. 2)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:57PM
3) Submerge other end of hose in clean glass jar partially
filled with clean brake fluid. Pump brake pedal several times, then
hold down. Open bleeder valve. Holding pedal down, close bleeder
valve. Release brake pedal.
4) Repeat procedure until brake fluid shows no signs of air
bubbles. When bleeding rear brakes, push lever of pressure regulator
in direction of rear axle.
5) After bleeding ABS vehicles, turn ignition on. Allow pump
to run until it shuts off. If pump runs longer than 2 minutes, allow
pump to cool for 10 minutes. On all vehicles, ensure master cylinder
reservoir is full.
ADJUSTMENTS
BRAKE PRESSURE REGULATOR
CAUTION: DO NOT adjust pressure regulator with brake pedal depressed.
1) Depress brake pedal once firmly. Release brake pedal
quickly, watching for regulator lever to move when pedal is released.
If regulator lever does not move when pedal is released, replace
regulator. If regulator lever moved, go to next step.
2) Ensure vehicle fuel tank is full, luggage compartment is
empty and a driver is in driver seat. Raise and support vehicle. Using
Pressure Gauges (US 1016), attach one gauge to right rear brake
cylinder or caliper. If vehicle is ABS-equipped, go to next step. If
vehicle is not ABS-equipped, go to step 4).
3) Using Distributor "T" (803 611 755) and an additional 8"
(203 mm) of brakeline, connect one gauge in front of pressure
regulator. Bleed pressure gauge and hoses through valve on gauges.
Lower vehicle. Bounce rear of vehicle several times. Go to step 5).
4) Attach Pressure Gauges (US 1016) to left front brake
caliper. Bleed pressure gauge and hoses through valve on gauges. Lower
vehicle. Bounce rear of vehicle several times.
5) Pump brake pedal several times. Press on brake pedal until
reading on front gauge shows pressure given for first reading in the
BRAKE PRESSURES table. Hold brake pressure to specification. Rear
gauge reading should be within specification given for first reading
in the BRAKE PRESSURES table.
6) Increase pressure on brake pedal until reading on front
gauge shows pressure given for second reading in the BRAKE PRESSURES
table. Hold brake pressure to specification. Rear gauge reading should
be within specification given for second reading in BRAKE PRESSURES
table. If pressures are within specification, brake pressure regulator
is functioning properly. If pressures are not within specification, go
to next step.
7) If pressure is too high, decrease spring pressure on
regulator. If pressure is too low, increase spring pressure on
regulator. If adjusting spring pressure on regulator does not bring
pressures within specification, replace pressure regulator. Disconnect
gauges, and bleed brakes.
Page 452 of 920
COMPUTER RELEARN PROCEDURES
Article Text (p. 2)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:58PM
"D" and allow engine to idle for one minute.
* Accelerate at normal throttle position (20-50%) until vehicle
shifts into top gear.
* Cruise at light to medium throttle.
* Decelerate to a stop, allowing vehicle to downshift, and use
brakes normally.
* Process may be repeated as necessary.
Manual Transmission
* Place transmission in Neutral position.
* Ensure emergency brake has been set and all accessories
are turned off.
* Start engine and bring to normal operating temperature.
* Allow vehicle to idle in Neutral for one minute.
* Initial relearn is complete: process will be completed during
normal driving.
Some manufacturers identify a specific relearn procedure
which will help establish suitable driveability during relearn stage.
These procedures are especially important if vehicle is equipped with
and electronically controlled automatic transmission or transaxle.
Always complete procedure before returning vehicle to customer.
END OF ARTICLE
Page 607 of 920
HOW TO USE SYSTEM WIRING DIAGRAMS
Article Text (p. 4)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 09:11PM
When trying to locate a component in a wiring diagram and you
don't know the specific system where it is located, use this handy
component locator to find the system wiring diagram in which the
component is located. Then, go to that system and locate the component
within the wiring diagram.
For example, if you don't know the specific system in which
the ignition switch is located, look up ignition switch in the wiring
diagram component location tables and go to the appropriate wiring
diagram(s) which contain either full or partial views of the ignition
switch. The full view of the ignition switch is located in Power
Distribution.
The first listing for the component will be the full or most
complete view of the component. Additional listings will be partial
views of the component. Not all components are used on all models.
All components will have a partial view in Ground
Distribution and Power Distribution. Data Link Connectors show
connecting circuits between modules. Alternate names for components
may be listed in wiring diagram component locations tables.
WIRING DIAGRAM COMPONENT LOCATIONS TABLEÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄComponent Wiring Diagram
ABS Electronic Control Unit ....................... Anti-Lock Brakes
Data Link Connectors
ABS Hydraulic Unit ................................ Anti-Lock Brakes
Acceleration Sensor ............................... Anti-Lock Brakes
Accessory Delay Relay ................................ Power Windows
A/C Compressor Clutch Relay ..................... Engine Performance
A/C Sensor ...................................... Engine Performance
A/C Pressure Switch ............................. Engine Performance
Adaptive Lamp Control Module ....................... Exterior Lights
Air Bag(s) ................................ Air Bag Restraint System
Air Bag Module ............................ Air Bag Restraint System
Air Bag Sensor(s) ......................... Air Bag Restraint System
Air Injection Pump Relay ........................ Engine Performance
Air Temperature Sensor ............................ Overhead Console
Alternator (Generator) ..................... Generators & Regulators
Anti-Theft Control Module ........................ Anti-Theft System
Starters
Autolamp Control Relay ........................... Headlight Systems
Daytime Running Lights
Automatic Shutdown (ASD) Relay .................. Engine Performance
Generators & Regulators
Autostick Switch ................................ Engine Performance
Auxiliary Battery Relay .................... Generators & Regulators
Back-Up Lights ...................................... Back-Up Lights
Exterior Lights
Barometric (BARO) Pressure Sensor ............... Engine Performance
Battery ......................................... Power Distribution
Battery Temperature Sensor ...................... Engine Performance
Page 611 of 920
HOW TO USE SYSTEM WIRING DIAGRAMS
Article Text (p. 8)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 09:11PM
Power Top Relay(s) ........................... Power Convertible Top
Powertrain Control Module ....................... Engine Performance
Analog Instrument Panels
Cruise Control Systems
Data Link Connectors
Generators & Regulators
Starters
Power Window Motors .................................. Power Windows
Power Window Relay(s) ................................ Power Windows
Radiator Fan Motor(s) ........................ Electric Cooling Fans
Radiator Fan Relay(s) ........................... Engine Performance
Electric Cooling Fans
Rainsense Module .............................. Wiper/Washer Systems
Raise Relay .................................. Power Convertible Top
Remote Anti-Theft Personality (RAP) Module ....... Anti-Theft System
Starters
Warning Systems
Seat Belt Pretensioners ................... Air Bag Restraint System
Seat Belt Retractor Solenoid .................... Passive Restraints
Seat Belt Switch .......................... Air Bag Restraint System
Passive Restraints
Shift Interlock Solenoid ................... Shift Interlock Systems
Shift Lock Actuator ........................ Shift Interlock Systems
Side Marker Lights ................................. Exterior Lights
SIR Coil Assembly (Clockspring) ........... Air Bag Restraint System
Slip Ring (Clockspring) ................... Air Bag Restraint System
Steering Column Switches
SRS Control Module ........................ Air Bag Restraint System
Starter Motor ............................................. Starters
Starter Interrupt Relay ................................... Starters
Starter Solenoid .......................................... Starters
Starter Relay ............................................. Starters
Steering Wheel Position Sensor .................... Anti-Lock Brakes
Stoplights ......................................... Exterior Lights
Stoplight Switch ................................ Engine Performance
Cruise Control Systems
Anti-Lock Brakes
Sun Roof ECU ........................................ Power Sun Roof
Sun Roof Motor ...................................... Power Sun Roof
Sun Roof Position Sensor ............................ Power Sun Roof
Taillights ......................................... Exterior Lights
Throttle Position (TP) Sensor ................... Engine Performance
Torque Converter Clutch Solenoid/Switch ......... Engine Performance
Traction Control Switch ........................... Anti-Lock Brakes
Trailer Tow Connector .............................. Exterior Lights
Trailer Tow Relay .................................. Exterior Lights
Transmission/Transaxle .......................... Engine Performance
Transmission Control Module (TCM) ............... Engine Performance
Starters
Transmission Range Sensor ................................. Starters
Back-Up Lights
Engine Performance