ad blue VOLKSWAGEN CORRADO 1993 Repair Manual

A/C SYSTEM GENERAL SERVICING
Article Text
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:48PM
ARTICLE BEGINNING
1993 GENERAL SERVICING
General Servicing Procedures
USING R-12 & R-134a REFRIGERANT
HANDLING/SAFETY PRECAUTIONS
1) Always work in a well-ventilated, clean area. Refrigerant
R-134a is colorless and is invisible as a gas. Refrigerant (R-12 or R-
134a) is heavier than oxygen and will displace oxygen in a confined
area. Avoid breathing refrigerant vapors. Exposure may irritate eyes,
nose and throat.
2) The system's high pressure can cause severe injury to eyes
and skin if a hose were to burst. Always wear eye protection when
working around A/C system and refrigerant. If necessary, wear rubber
gloves or other protective clothing.
3) Refrigerant evaporates quickly when exposed to atmosphere,
freezing anything it contacts. If liquid refrigerant contacts eyes or
skin, DO NOT rub eyes or skin. Immediately flush affected area with
cool water for 15 minutes and consult a doctor or hospital.
4) Never use R-134a in combination with compressed air for
leak testing. Pressurized R-134a in the presence of oxygen (air
concentrations greater than 60% by volume) may form a combustible
mixture. DO NOT introduce compressed air into R-134a containers (full
or empty), A/C system components or service equipment.
5) DO NOT expose A/C system components to high temperatures,
steam cleaning for example, as excessive heat will cause
refrigerant/system pressure to increase. Never expose refrigerant
directly to open flame. If refrigerant needs to be warmed, place
bottom of refrigerant tank in warm water. Water temperature MUST NOT
exceed 125øF (52øC).
6) Use care when handling refrigerant containers. DO NOT
drop, strike, puncture or incinerate containers. Use Department Of
Transportation (DOT) approved, DOT 4BW or DOT 4BA, refrigerant
containers.
7) Never overfill refrigerant containers. The safe filling
level of a refrigerant container MUST NOT exceed 60% of the
container's gross weight rating. Store refrigerant containers at
temperature less than 125
øF (52øC).
8) R-12 refrigerant (Freon) will be sold and stored in White
containers, while R-134a refrigerant will be sold and stored in 30 or
50-pound Light Blue containers.
9) R-12 and R-134a refrigerants must never be mixed, as their
desiccants and lubricants are not compatible. If the refrigerants are
mixed, system cross-contamination or A/C system component failure may
occur. Always use separate servicing and refrigerant
recovery/recycling equipment.
10) Follow equipment manufacturer instructions of all service
equipment to be used. The Material Safety Data Sheet (MSDS), provided
by refrigerant manufacturer/suppliers, contains valuable information

A/C SYSTEM GENERAL SERVICING
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 08:48PM
regarding the safe handling of R-12 or R-134a refrigerants.
IDENTIFYING R-134a SYSTEMS & COMPONENTS
To prevent refrigerant cross-contamination, use following
methods to identify R-134a based systems and components.
Fittings & "O" Rings
All R-134a based A/C systems use 1/2" - 16" ACME threaded
fittings (identifiable by square threads) and quick-connect service
couplings. See Fig. 1. Besides the use of these fittings, most
manufacturers will use Green colored "O" rings in R-134a systems.Fig. 1: R-134a Fittings & Quick Connect Service Couplings ID
Courtesy of Audi of America, Inc.
Underhood A/C Specification Labels
Most R-134a based systems will be identified through the use
of Green or Light Blue underhood labels, or with R-134a refrigerant
clearly printed on labels. See Fig. 2. Some manufacturers will
identify R-12 based systems with White, Red, Silver or Gold underhood
labels. Before servicing an A/C system, always determine which
refrigerant is being used.

A/C SYSTEM GENERAL SERVICING
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 08:48PM
Because R-134a is not interchangeable with R-12, separate
sets of hoses, manifold gauge set and recovery/recycling equipment are
required to service vehicles. This is necessary to avoid cross-
contaminating and damaging system.
All equipment used to service systems using R-134a must meet
SAE standard J1991. The service hoses on the manifold gauge set must
have manual (turn wheel) or automatic back-flow valves at the service
port connector ends. This will prevent refrigerant from being released
into the atmosphere.
For identification purposes, R-134a service hoses must have a
Black stripe along its length and be clearly labeled SAE J2196/R-134a.
The low pressure test hose is Blue with a Black stripe. The high
pressure test hose is Red with a Black stripe, and the center test
hose is Yellow with a Black stripe.
NOTE: Refrigerant R-12 service hoses will ONLY be labeled SAE
J2196.
R-134a manifold gauge sets can be identified by one or all of
the following:
* Labeled FOR USE WITH R-134a on set
* Labeled HFC-134 or R-134a on gauge face
* Light Blue color on gauge face
In addition, pressure/temperature scales on R-134a gauge sets
are different from R-12 manifold gauge sets.
SYSTEM SERVICE VALVES
SCHRADER-TYPE VALVES
NOTE: Although similar in construction and operation to a tire
valve, NEVER replace a Schrader-type valve with a tire valve.
Schrader valve is similar in construction and operation to a
tire valve. When a test gauge hose with built-in valve core depressor
is attached, Schrader stem is pushed inward to the open position and
allows system pressure to reach gauge.
If test hose does not have a built-in core depressor, an
adapter must be used. Never attach hose or adapter to Schrader valve
unless it is first connected to manifold gauge set.
Refrigerant R-12 Schrader-type valve cores have TV5 thread
size. Refrigerant R-134a Schrader-type valve cores use M6 (Metric)
threads. R-134a valve cores can be easily identified by use of "O"
rings and external spring. See Fig. 1.
SERVICE VALVE LOCATIONS
SERVICE VALVE LOCATIONS TABLEÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄVehicle High Low

A/C-HEATER SYSTEM - MANUAL
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 08:49PM
too low. This protects compressor if not enough refrigerant is in
system. Low-pressure cut-out switch shuts compressor off at about 29
psi (2.0 kg/cmý).
THERMOSWITCH
Thermoswitch shuts compressor off if coolant temperature is
greater than 248
øF (120øC).
ADJUSTMENTS
AIR DISTRIBUTION CONTROL
1) Move air distribution control knob to defrost position.
Connect 3-foot long control cable to footwell/defrost flap lever. Push
flap lever toward cable and secure cable sheath with retainer clip.
2) Move air distribution control knob to panel (vent)
position. Connect 2-foot long control cable to center flap lever. Push
flap lever away from cable and secure cable sheath with retainer clip.
TEMPERATURE CONTROL
Move temperature knob to full cool position. Connect
temperature control cable (Blue sheath) to temperature flap lever.
Push flap lever away from cable and secure cable sheath with retainer
clip.
TROUBLE SHOOTING
NO COOLING
1) Ensure blower fan motor operates in all 4 speeds. Ensure
air duct closes off outside air and heater water valve is closed.
Clean condenser.
2) Inspect receiver-drier pressure seal. If seal is good, go
to step 3). If seal is broken, replace seal. Evacuate and recharge
system. If system cools properly, testing is complete. If system does
not cool, connect pressure gauges.
3) Adjust engine speed to 2500 RPM. Set controls for maximum
cooling and high fan. Insert thermometer in left air duct and close
all other ducts. With vehicle in shade, close windows and doors and
connect pressure gauges. Operate system for 10 minutes.
4) If fan does not operate, replace pressure switch. Ensure
system is okay. If fan does come on, turn engine off, and check for
condenser obstructions and blocked airflow.
5) Turn air conditioner on and off with temperature control.
Ensure compressor clutch engages. Push lever to extreme right position
and back again. A click should be heard from compressor clutch. If a
click is not heard, check for voltage at clutch coil wire with switch
on. If voltage is present, replace clutch coil. If voltage is not
present, check wiring or replace thermostatic switch.
6) If compressor clutch operates, check gauge readings. If

ABBREVIATIONS
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 08:49PM³Assy. ³Assembly ³
³Auto.
³Automatic ³
³Aux.
³Auxiliary ³
³Avg.
³Average ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ "B" ABBREVIATION TABLE
"B" ABBREVIATION TABLE
ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³ABBREVIATION
³DEFINITION ³
ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´
³B/P
³Backpressure ³
³BAC
³By-Pass Air Control ³
³BAP
³Barometric Absolute Pressure Sensor ³
³BARO
³Barometric ³
³BBDC
³Before Bottom Dead Center ³
³BCM
³Body Control Module ³
³BDC
³Bottom Dead Center ³
³BHP
³Brake Horsepower ³
³BLK
³Black ³
³BLU
³Blue ³
³BMAP
³Barometric & Manifold Absolute Pressure Sensor ³
³BOO
³Brake On-Off Switch ³
³BP
³Barometric Pressure sensor ³
³BPS
³Barometric Pressure Sensor ³
³BPT
³Backpressure Transducer ³
³BRN
³Brown ³
³BTDC
³Before Top Dead Center ³
³BTU
³British Thermal Unit ³
³BVSV
³Bimetallic Vacuum Switching Valve ³
³Baro.
³Barometric ³
³Batt.
³Battery ³
³Bbl.
³Barrel (Example: 4-Bbl.) ³
³Blst.
³Ballast ³
³Blwr.
³Blower ³
³Brkr.
³Breaker ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ "C" ABBREVIATION TABLE
"C" ABBREVIATION TABLE
ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³ABBREVIATION
³DEFINITION ³
ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´
³ø C
³Celsius (Degrees) ³
³C(3) I
³Computer Controlled Coil Ignition ³
³C(4)
³Computer Controlled Catalytic Converter ³
³CANP
³Canister Purge solenoid ³
³CARB
³California Air Resources Board ³
³CAT
³Catalytic Converter ³
³CB
³Circuit Breaker ³

ABBREVIATIONS
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 08:49PM³DDD ³Dual Diaphragm Distributor ³
³DERM
³Diagnostic Energy Reserve Module ³
³DFI
³Digital Fuel Injection ³
³DIC
³Driver Information Center ³
³DIS
³Direct Ignition System ³
³DIS
³Distributorless Ignition System ³
³DIST
³Distribution ³
³DISTR
³Distributor ³
³DK BLU
³Dark Blue ³
³DK GRN
³Dark Green ³
³DME
³Digital Motor Electronics (Motronic System) ³
³DOHC
³Double Overhead Cam ³
³DOT
³Department of Transportation ³
³DP
³Dashpot ³
³DRB-II
³Diagnostic Readout Box ³
³DVOM
³Digital Volt/Ohm Meter (see VOM) ³
³Def.
³Defogger or Defroster ³
³Def.
³Defrost ³
³Defog.
³Defogger ³
³Diag.
³Diagnostic ³
³Dist.
³Distributor or Distribution ³
³Dr.
³Door ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ "E" ABBREVIATION TABLE
"E" ABBREVIATION TABLE
ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³ABBREVIATION
³DEFINITION ³
ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´
³EAC
³Electric Assist Choke ³
³EACV
³Electric Air Control Valve ³
³EBCM
³Electronic Brake Control Module ³
³ECA
³Electronic Control Assembly ³
³ECAT
³Electronically Controlled Automatic Transaxle ³
³ECM
³Electronic Control Module ³
³ECT
³Engine Coolant Temperature Sensor ³
³ECU
³Electronic Control Unit or Engine Control Unit ³
³EDF
³Electric Drive Fan relay assembly ³
³EDIS
³Electronic Distributorless Ignition System ³
³EEC
³Electronic Engine Control ³
³EECS
³Evaporative Emission Control System ³
³EEPROM
³Electronically Erasable PROM ³
³EFE
³Early Fuel Evaporation ³
³EFI
³Electronic Fuel Injection ³
³EGO
³Exhaust Gas Oxygen sensor (see HEGO) ³
³EGR
³Exhaust Gas Recirculation system ³
³EGRC
³EGR Control solenoid or system ³
³EGRV
³EGR Vent solenoid or system ³
³EMR
³Emission Maintenance Reminder Module ³
³ESA
³Electronic Spark Advance ³
³ESC
³Electronic Spark Control ³

ABBREVIATIONS
Article Text (p. 7)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:49PM³Inj. ³Injector ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ "J" ABBREVIATION TABLE
"J" ABBREVIATION TABLE
ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³ABBREVIATION
³DEFINITION ³
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³J/B
³Junction Block ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ "K" ABBREVIATION TABLE
"K" ABBREVIATION TABLE
ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³ABBREVIATION
³DEFINITION ³
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³k/ohms
³1000 ohms (kilo as in k/ohms) ³
³kg
³Kilograms (weight) ³
³kg/cm
ý ³Kilograms Per Square Centimeter ³
³KAM
³Keep Alive Memory ³
³KAPWR
³Keep Alive Power ³
³KM/H
³Kilometers Per Hour ³
³KOEO
³Key On Engine Off ³
³KOER
³Key On Engine Running ³
³KS
³Knock Sensor ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ "L" ABBREVIATION TABLE
"L" ABBREVIATION TABLE
ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³ABBREVIATION
³DEFINITION ³
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³L
³Liter(s) ³
³L/D
³Light Duty ³
³LCD
³Liquid Crystal Display ³
³LED
³Light Emitting Diode ³
³LH
³Left Hand ³
³LOS
³Limited Operation Strategy ³
³LT BLU
³Light Blue ³
³LT GRN
³Light Green ³
³LUS
³Lock-Up Solenoid ³
³Lbs.
³Pounds ³
³Lt(s).
³Light(s) ³
³Lugg.
³Luggage ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ "M" ABBREVIATION TABLE

ANTI-LOCK BRAKE SYSTEM
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 08:57PM
ABS Main Valve Continuity Test
Using an ohmmeter, check for continuity between ABS main
valve terminal No. 1 (Black wire) and ECU connector terminal No. 18,
and between ABS main valve terminal No. 2 (Brown wire) and ground.
There should be continuity at both test points. If there is no
continuity at both test points, repair wiring and retest.
Rear Hydraulic Modulator Inlet Valve Resistance Test
Using an ohmmeter, measure resistance between ECU connector
terminals No. 11 and 17. See Fig. 2. If resistance is 5-7 ohms, go to
next test. If resistance is not 5-7 ohms, measure between hydraulic
modulator block terminals No. 1 (Brown wire) and No. 5 (Gray wire).
See Fig. 4. If resistance is 5-7 ohms, check wiring between hydraulic
modulator and ECU for open circuit. If resistance is not 5-7 ohms,
replace hydraulic modulator.
Right Front Hydraulic Modulator Inlet Valve Resistance Test
Using an ohmmeter, measure resistance between ECU connector
terminals No. 11 and 15. See Fig. 2. If resistance is 5-7 ohms, go to
next test. If resistance is not 5-7 ohms, measure between hydraulic
modulator terminals No. 1 (Brown wire) and No. 2 (Yellow wire). See
Fig. 4. If resistance is 5-7 ohms, check wiring between hydraulic
modulator and ECU for open circuit. If resistance is not 5-7 ohms,
replace hydraulic modulator.
Left Front Hydraulic Modulator Inlet Valve Resistance Test
Using an ohmmeter, measure resistance between ECU connector
terminals No. 11 and 35. See Fig. 2. If resistance is 5-7 ohms, go to
next test. If resistance is not 5-7 ohms, measure between hydraulic
modulator terminals No. 1 (Brown wire) and No. 7 (Blue or Black/Green
wire). See Fig. 4. If resistance is 5-7 ohms, check wiring between
valve block and ECU for open circuit. If resistance is not 5-7 ohms,
replace hydraulic modulator.
Rear Hydraulic Modulator Outlet Valve Resistance Test
Using an ohmmeter, measure resistance between ECU connector
terminals No. 11 and 33. See Fig. 2. If resistance is 3-5 ohms, go to
next test. If resistance is not 3-5 ohms, measure between valve block
terminals No. 1 (Brown wire) and No. 4 (White wire). See Fig. 4. If
resistance is 3-5 ohms, check wiring between hydraulic modulator and
ECU for open circuit. If resistance is not 3-5 ohms, replace hydraulic
modulator.
Right Hydraulic Modulator Block Outlet Valve Resistance Test
Using an ohmmeter, measure resistance between ECU connector
terminals No. 11 and 34. See Fig. 2. If resistance is 3-5 ohms, go to
next test. If resistance is not 3-5 ohms, measure between hydraulic
modulator terminals No. 1 (Brown wire) and No. 3 (Green wire). See
Fig. 4. If resistance is 3-5 ohms, check wiring between hydraulic
modulator and ECU for open circuit. If resistance is not 3-5 ohms,
replace hydraulic modulator.

ANTI-LOCK BRAKE SYSTEM
Article Text (p. 10)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 08:57PM
Left Front Hydraulic Modulator Outlet Valve Resistance Test
Using an ohmmeter, measure resistance between ECU connector
terminals No. 11 and 16. See Fig. 2. If resistance is 3-5 ohms, go to
next test. If resistance is not 3-5 ohms, measure between hydraulic
modulator terminals No. 1 (Brown wire) and No. 6 (Black/Blue wire).
See Fig. 4. If resistance is 3-5 ohms, check wiring between hydraulic
modulator and ECU for open circuit. If resistance is not 3-5 ohms,
replace hydraulic modulator.
Hydraulic Modulator/Pump Relay Resistance Test
Turn ignition off. Unplug pressure switch connector from
hydraulic modulator. Using an ohmmeter, measure resistance between ECU
connector terminals No. 2 and 14. See Fig. 2. If resistance is 50-100
ohms, go to next test. If resistance is not 50-100 ohms, check wiring.
If wiring is faulty, repair wiring and retest. If wiring is okay,
replace relay and retest.
ABS Main Valve Function Test
Connect a jumper wire between ECU connector terminals No. 2
and 18. See Fig. 2. Depress brake pedal. Turn ignition on. Brake pedal
should rise slightly. If brake pedal did not rise slightly, check
wiring between terminals and hydraulic modulator. If wiring is okay,
replace hydraulic modulator.
Hydraulic Modulator/Pump Test
Turn ignition off. Depress brake pedal 25 times. Turn
ignition on. BRAKE and ANTILOCK lights should come on for 2-60
seconds. Pump should operate for 2-60 seconds, then turn off. If
lights do not come on, check wiring and warning light bulbs, and
retest. Also check bulb(s). If lights come on, then turn off, and pump
operates for 60 seconds maximum, then turns off, go to next test. If
pump does not operate and all other preceding tests have been
performed, replace hydraulic modulator/pump.
CAUTION: During VALVE BLOCK FUNCTION TESTS, DO NOT turn ignition on
longer than 60 seconds during any test.
Rear Valve Block Function Test
Connect a jumper wire ECU between ECU connector terminals No.
2, 17 and 33. See Fig. 2. Depress brake pedal. Rear wheels should be
locked up. Turn ignition on. Rear wheels should rotate. If wheels do
not rotate, replace hydraulic modulator. Turn ignition off.
Right Front Valve Block Function Test
Connect a jumper wire ECU between ECU connector terminals No.
2, 15 and 34. See Fig. 2. Depress brake pedal. Right front wheel
should be locked up. Turn ignition on. Right front wheel should
rotate. If wheel does not rotate, replace hydraulic modulator. Turn
ignition off.
Left Front Valve Block Function Test

ELECTRICAL COMPONENT LOCATOR
Article Text (p. 24)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 09:09PM ECM (Blue) On thermostat housing, on
left rear of engine.