technical data VOLKSWAGEN CORRADO 1993 User Guide

G - TESTS W/CODES
Article Text (p. 6)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 09:11PM
Corrado SLC (2.8L)
1) Connect Scan Tester (VAG 1551) to Data Link Connectors
(DLC) located in center console, in front of shift lever. With scan
tester in OUTPUT DIAGNOSTIC TEST MODE, the injectors, Idle Air Control
(IAC) valve, evaporative frequency (solenoid) valve, oxygen sensor
relay, and EGR frequency valve (if equipped) may be actuated in
sequence listed.
2) The injector(s) must click by opening and closing
throttle. To trigger injectors 2 through 6, open and close throttle
once for each injector. If injector(s) do(es) not click, test
circuit(s) using the J - PIN VOLTAGE CHARTS article.
3) If injectors are okay, switch to next output test by
pressing the right arrow button. Press right arrow button to actuate
IAC valve. IAC valve must pulsate noticeably until switched to next
output test by pressing the right arrow button.
4) If IAC valve does not pulsate, turn ignition off.
Disconnect IAC valve and connect LED Tester (US 1115) to IAC valve
wiring harness connector using jumper wires from Adapter Kit (VW
1594).
5) Turn ignition on and repeat IAC valve output test. If LED
blinks, replace IAC valve. If LED does not blink, test circuit using
the J - PIN VOLTAGE CHARTS article in this section. If IAC and circuit
are okay, replace ECM.
6) If IAC valve pulsates properly, locate evaporative
frequency solenoid valve (located behind air cleaner housing, on
wheelwell). Disconnect hose, coming from fuel vapor canister, from
frequency solenoid. Attach auxiliary hose to solenoid.
7) Blow into auxiliary hose, in direction of throttle
housing, while performing solenoid output test (pressing right arrow
button to actuate evaporative frequency solenoid). If solenoid does
not actuate (open and close), disconnect wiring harness from solenoid.
Connect LED tester to solenoid wiring harness connector using jumper
wires from adapter kit.
8) Repeat evaporative solenoid valve output test. If LED
blinks, replace evaporative frequency solenoid valve. If LED does not
blink, test circuit using the J - PIN VOLTAGE CHARTS article. If
evaporative solenoid valve and circuit are okay, replace ECM.
9) If evaporative frequency solenoid operates properly, press
right arrow button to actuate oxygen sensor relay (mounted on
fuse/relay panel with a clip). If relay does not click, test relay and
its circuit using the J - PIN VOLTAGE CHARTS article.
10) If relay operates properly, press right arrow button to
actuate EGR frequency valve. Frequency valve must click until test
mode is switched to next output test by pressing the right arrow
button.
11) If frequency valve does not click, disconnect valve.
Connect LED tester using jumper wires from Adapter Kit (VAG 1594) to
frequency valve wiring harness connector.
12) If LED blinks, replace EGR frequency valve. If LED does
not blink, test circuit using the J - PIN VOLTAGE CHARTS article. If
EGR frequency valve and circuit are okay, replace ECM.
13) If EGR frequency valve operates properly, press right

G - TESTS W/CODES
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 09:11PM
arrow button twice to select END OUTPUT function on scan tester. Press
"Q" to enter input. Turn ignition off. Disconnect scan tester.
READ MEASUREMENT & READ MEASURING (TEST) VALUE BLOCK
NOTE: See ENTERING SELF-DIAGNOSTICS for additional scan tester
operating instructions.
Corrado SLC (2.8L)
1) Connect Scan Tester (VAG 1551) to Data Link Connectors
(DLC) located in center console, in front of shift lever. With scan
tester in READ MEASURING VALUE BLOCK function, press "01" to "06"
buttons to select desired display group. See appropriate DISPLAY GROUP
table.
2) When display group is selected, only the second number is
shown on display (the zero does not appear on display). With READ
MEASUREMENT BLOCK function completed, select END OUTPUT function on
scan tester. Turn ignition off. Disconnect scan tester.
DISPLAY GROUP (CORRADO SLC)ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄDisplay Group Number Display
& Channel Number Parameters
01
1 ..................................... Engine Speed
2 ....................... Engine Coolant Temperature
3 ............................. Oxygen Sensor Signal
4 .................................. Ignition Timing
02
1 ..................................... Engine Speed
2 ................................... Injection Time
3 ................................... System Voltage
4 .................. EGR Temperature (If Applicable)
03
1 ..................................... Engine Speed
2 ...................................... Engine Load
3 ................................... Throttle Angle
4 ............. Intake Air Temperature (At Manifold)
04
1 ..................................... Engine Speed
2 ...................................... Engine Load
3 .................................... Vehicle Speed
4 .............. Switch Positions (Operating Status)
05
1 ..................................... Engine Speed
2 ..................... Idle Air Control (IAC) Valve
3 ................................... IAC Duty Cycle
4 ............ Switch Positions (A/C & Auto. Trans.)
06
1 ............................. Oxygen Sensor Signal
2 ........... Oxygen Sensor Adaptive Learning (Idle)

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

HOW TO USE SYSTEM WIRING DIAGRAMS
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 09:11PM
Body Control Module .......................... Body Control Computer
Anti-Theft System
Daytime Running Lights
Engine Performance
Headlight Systems
Warning Systems
Boost Control Solenoid .......................... Engine Performance
Boost Sensor .................................... Engine Performance
Brake Fluid Level Switch .................. Analog Instrument Panels
Brake On/Off (BOO) Switch ................... Cruise Control Systems
Engine Performance
Shift Interlock Systems
Buzzer Module ...................................... Warning Systems
Camshaft Position (CMP) Sensor .................. Engine Performance
Central Control Module ........................... Anti-Theft System
Clockspring ............................... Air Bag Restraint System
Cruise Control Systems
Steering Column Switches
Clutch Pedal Position Switch .............................. Starters
Clutch Start Switch ....................................... Starters
Combination Meter ......................... Analog Instrument Panels
Constant Control Relay Module (CCRM) ............ Engine Performance
Electric Cooling Fans
Convenience Center .............................. Power Distribution
Illumination/Interior Lights
Convertible Top Motor ........................ Power Convertible Top
Convertible Top Switch ....................... Power Convertible Top
Crankshaft Position (CKP) Sensor ................ Engine Performance
Cruise Control Module ....................... Cruise Control Systems
Cruise Control Switch ....................... Cruise Control Systems
Condenser Fan Relay(s) ....................... Electric Cooling Fans
Data Link Connector (DLC) ....................... Engine Performance
Daytime Running Lights Module ............... Daytime Running Lights
Exterior Lights
Defogger Relay ................................ Rear Window Defogger
Diagnostic Energy Reserve Module (DERM) ... Air Bag Restraint System
Discriminating Sensor (Air Bag) ........... Air Bag Restraint System
Distributor ..................................... Engine Performance
Door Lock Actuators ............................... Power Door Locks
Remote Keyless Entry
Door Lock Relay(s) ................................ Power Door Locks
Electrochromic Mirror ................................ Power Mirrors
Electronic Level Control (ELC)
Height Sensor .............................. Electronic Suspension
Electronic Level Control (ELC) Module ........ Electronic Suspension
Engine Coolant Temperature (ECT)
Sending Unit ............................ Analog Instrument Panels
Engine Coolant Temperature (ECT) Sensor ......... Engine Performance
Engine Control Module ........................... Engine Performance
Generators & Regulators
Starters
ETACS ECU .......................................... Warning Systems

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

HOW TO USE SYSTEM WIRING DIAGRAMS
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 09:11PM
Transmission Range Switch ........................... Back-Up Lights
Engine Performance
Anti-Theft System
Turn Signal Flasher ................................ Exterior Lights
Turn Signal Lights ................................. Exterior Lights
Twilight Sentinel Switch ......................... Headlight Systems
Daytime Running Lights
Vapor Canister Leak Detection Pump .............. Engine Performance
Vehicle Control Module (VCM) .................... Engine Performance
Vehicle Dynamic Module ....................... Electronic Suspension
Vehicle Speed Control Servo ................. Cruise Control Systems
Vehicle Speed Sensor .......................... Data Link Connectors
Analog Instrument Panels
Cruise Control Systems
Electronic Suspension
Voltage Regulator .......................... Generators & Regulators
Water-In-Fuel Sensor ............................ Engine Performance
Analog Instrument Panels
Wheel Speed Sensors ............................... Anti-Lock Brakes
Window Timer Module .......................... Power Convertible Top
Windshield Intermittent Wiper Relay ........... Wiper/Washer Systems
Windshield Washer Motor ....................... Wiper/Washer Systems
Wiper Motor ................................... Wiper/Washer SystemsÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄEND OF ARTICLE

I - SYSTEM/COMPONENT TESTS
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 09:11PM
COMPUTERIZED ENGINE CONTROLS
ELECTRONIC CONTROL MODULE (ECM)
Ground & Power Circuits
Check ECM ground and power circuits using the values in the
appropriate J - PIN VOLTAGE CHARTS article.
ENGINE SENSORS & SWITCHES
ENGINE COOLANT TEMPERATURE SENSOR
Corrado SLC (2.8L)
1) Ensure engine is cold. Connect Scan Tester (VAG 1551) to
Data Link Connectors (DLC) located in center console, in front of
shift lever. Start engine and allow it to idle.
2) With scan tester in READ TEST VALUE BLOCK function, select
group No. 01 and read coolant temperature value in field No. 2 of scan
tester. Temperature value must increase uniformly without
interruption. If value increases as specified, select END OUTPUT
function on scan tester.
3) If displayed value does not change or if engine
malfunctions during certain temperature ranges, turn ignition off and
measure engine coolant temperature sensor resistance. See ENGINE
COOLANT TEMPERATURE SENSOR RESISTANCE table.
ENGINE COOLANT TEMPERATURE SENSOR RESISTANCEÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄTemperature
øF (øC) Ohms
68 (20) ......................... 3000-2000
86 (30) ......................... 2000-1500
104 (40) ........................ 1500-1000
122 (50) ......................... 1000-800
140 (60) .......................... 700-500
158 (70) .......................... 500-375
176 (80) .......................... 375-275
194 (90) .......................... 275-225
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ INTAKE AIR TEMPERATURE SENSOR
Corrado SLC (2.8L)
1) Turn ignition off. Disconnect intake air temperature
sensor. Remove sensor from intake manifold and plug opening in
manifold. Reconnect sensor to wiring harness.
2) Connect Scan Tester (VAG 1551) to Data Link Connectors
(DLC) located in center console, in front of shift lever. Start engine
and allow it to idle. With scan tester in READ TEST VALUE BLOCK
function, select group 03 and read intake air temperature sensor value
in field No. 4 of scan tester.
3) Spray sensor with cooling spray and observe value on scan

I - SYSTEM/COMPONENT TESTS
Article Text (p. 3)
1993 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, March 22, 2000 09:11PM
tester. Scan tester value must decrease. If temperature value does not
change, repair intake air temperature sensor circuit or replace sensor
as necessary. After repairs, erase Diagnostic Trouble Code (DTC)
memory (if applicable) and select END OUTPUT function.
HALL EFFECT SENSOR
Corrado SLC (2.8L)
Testing information is not available from manufacturer. These
vehicles are equipped with a distributorless ignition system.
FUEL SYSTEM
ACCELERATION/FULL THROTTLE ENRICHMENT & DECELERATION FUEL
CUT-OFF
Corrado SLC (2.8L)
1) Ensure engine coolant temperature is at least 176øF
(80
øC). Connect Scan Tester (VAG 1551) to Data Link Connectors (DLC)
located in center console, in front of shift lever.
2) Start engine and allow it to idle. With scan tester in
READ TEST VALUE BLOCK function, select group No. 04 and read value in
field No. 4 of scan tester. Display value must be 00010 at idle.
3) Using accelerator pedal, increase engine speed to 3000 RPM
and observe scan tester. Display value in field No. 4 of scan tester
must briefly be 10100. Release accelerator pedal and observe scan
tester.
4) Display value in field No. 4 of scan tester must briefly
be 00011, then return to 00010 at idle. If values are not as
specified, see THROTTLE POSITION (TP) SENSOR ADJUSTMENT procedures in
the D - ADJUSTMENTS article. If values are as specified, select END
OUTPUT function on scan tester.
FUEL INJECTORS & CIRCUIT
Corrado SLC (2.8L)
1) To access fuel injectors, remove ignition wires. Remove
hose from mass airflow sensor. Disconnect hose to fuel evaporative
(frequency) solenoid valve at throttle body.
2) Disconnect throttle position sensor and idle air control
valve. Disconnect accelerator cable from throttle body. Disconnect and
plug coolant hoses at throttle body.
3) Disconnect hose from air intake heated tube. Detach fuel
lines at cylinder head cover and remove from fuel rail. Disconnect
vacuum hose from fuel pressure regulator. Remove intake manifold upper
section. See Fig. 2.
4) With intake manifold upper section removed, disconnect
wiring harness from fuel injectors. Using a Digital Volt-Ohmmeter
(DVOM) and test leads from Adapter Kit (VW 1594), check fuel injector
resistance. See Fig. 3.
5) Fuel injector resistance should be 15.0-21.5 ohms. If
resistance is zero ohms, check for a short circuit in wiring harness.

I - SYSTEM/COMPONENT TESTS
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 09:11PM
reinstalling fuel rail, ensure that "O" rings are not damaged.Fig. 3: Testing Fuel Injectors & Circuit (Corrado SLC)
Courtesy of Volkswagen United States, Inc.
OXYGEN SENSOR CONTROL
IDLE CONTROL SYSTEM
IDLE AIR CONTROL (IAC) VALVE
Corrado SLC (2.8L)
1) Connect Scan Tester (VAG 1551) to Data Link Connectors
(DLC) located in center console, in front of shift lever. With scan
tester in OUTPUT DIAGNOSTIC TEST MODE, test IAC valve. For more
information, see the G - TESTS W/CODES article in this section.
2) To check IAC valve triggering circuit, turn ignition off.
Disconnect wiring harness connector from idle air control valve.
Connect LED Tester (US 1115) to wiring harness connector terminals No.
1 and 2.
3) Turn ignition on. Perform OUTPUT DIAGNOSTIC TEST MODE
until IAC valve is triggered. LED tester must flash. If LED tester
does not flash, check IAC valve circuit.
4) If LED tester flashes, disconnect wiring harness connector
from idle air control valve. Using Test Leads from Adapter Kit (VW
1594), connect DVOM to IAC valve terminals No. 1 and 2. IAC valve
resistance must be 10-20 ohms. If resistance is incorrect, replace IAC
valve.
IGNITION SYSTEM
NOTE: Ignition system testing information is not available
from manufacturer. These vehicles are equipped with a
distributorless ignition system.

J - PIN VOLTAGE CHARTS
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 09:14PM
Connector & Jumper
Terminals No 1 & 2. ... 1.5 Ohms Max.
EGR Temperature
Sensor (15 & 33) ....... Disconnect Sensor
Connector & Jumper
Terminals No 1 & 2. ... 1.5 Ohms Max.
(1) - TESTING CONDITIONS: Disconnect harness connector from ECM.
Connect Test Box (VAG 1598/18) to ECM harness connector, leaving
the ECM disconnected.
(2) - With ignition off, jumper terminals No. 9 and No. 55 of the
test box.
(3) - Refer to the I - SYS/COMP TESTS article.
(4) - These are terminal connectors at data link connector.
(5) - 3-pin connector is located at rear of engine mount.
(6) - 3-pin Black connector is located next to starter.
(7) - 3-pin White connector is located next to starter.ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄEND OF ARTICLE