Page 611 of 906

J - PIN VOLTAGE CHARTS
Article Text
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:46PM
ARTICLE BEGINNING
1990 ENGINE PERFORMANCE
Pin Voltage & Sensor Operating Ranges
Volkswagen; Corrado, Fox, Golf, Jetta, Vanagon
NOTE: Cabriolet pin voltage and sensor operating range charts are
not available from manufacturer.
INTRODUCTION
Pin voltage charts are supplied to reduce diagnostic time.
Checking pin voltages at the ECU determines whether it's receiving and
transmitting proper voltage signals. Charts may also help determine if
ECU harness is shorted or opened.
NOTE: Voltage readings may vary slightly due to battery condition
or charging rate. All voltage tests should be performed with
a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm
input impedance, unless stated otherwise in testing
procedure.Fig. 1: Typical ECU Terminal Pin Connector
Courtesy of Volkswagen United States, Inc.
NOTE: Cabriolet voltage and resistance checks are not available
from manufacturer.
Page 617 of 906

K - SENSOR RANGE CHARTS
Article Text
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:46PM
ARTICLE BEGINNING
1990 ENGINE PERFORMANCE
Pin Voltage & Sensor Operating Ranges
Volkswagen; Corrado, Fox, Golf, Jetta, Vanagon
NOTE: Cabriolet pin voltage and sensor operating range charts are
not available from manufacturer.
INTRODUCTION
Pin voltage charts are supplied to reduce diagnostic time.
Checking pin voltages at the ECU determines whether it's receiving and
transmitting proper voltage signals. Charts may also help determine if
ECU harness is shorted or opened.
NOTE: Voltage readings may vary slightly due to battery condition
or charging rate. All voltage tests should be performed with
a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm
input impedance, unless stated otherwise in testing
procedure.Fig. 1: Typical ECU Terminal Pin Connector
Courtesy of Volkswagen United States, Inc.
NOTE: Cabriolet voltage and resistance checks are not available
from manufacturer.
Page 623 of 906
L - WIRING DIAGRAMS
Article Text
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:46PM
ARTICLE BEGINNING
1990 ENGINE PERFORMANCE
Wiring Diagrams
Volkswagen; Cabriolet, Corrado, Fox, Golf GL/GTI,
Jetta, VanagonFig. 1: Cabriolet 1.8L Wiring Diagram
Page 630 of 906
M - VACUUM DIAGRAMS
Article Text
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:48PM
ARTICLE BEGINNING
1990-91 ENGINE PERFORMANCE
Volkswagen Vacuum Diagrams
Cabriolet, Corrado, Fox, Golf GL/GTI,
Jetta, Passat, Vanagon
INTRODUCTION
This article contains underhood views of vacuum hose routing.
Use these vacuum diagrams during the visual inspection of F - BASIC
TESTING article. This will assist in identifying improperly routed
vacuum hoses which cause driveability and/or computer-indicated
malfunctions.Fig. 1: Fox Vacuum Diagram
Courtesy of Volkswagen United States, Inc.
Page 634 of 906
M - VACUUM DIAGRAMS
Article Text (p. 5)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:48PMFig. 8: Canister-to-Intake Manifold Vacuum Diagram (AFC-Digifant
II System)
Courtesy of Volkswagen United States, Inc.Fig. 9: Vanagon Crankcase Ventilation Vacuum Diagram
Courtesy of Volkswagen United States, Inc.Fig. 10: 1.8L 8-Valve Engine Crankcase Ventilation Vacuum Diagram
Courtesy of Volkswagen United States, Inc.
Page 637 of 906

MAINTENANCE INFORMATION
Article Text (p. 2)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:48PM
5 - Engine
B * 1.8L 4-Cyl. G-60 Supercharged Digifant FI, 158 HP (1990-92)
D * 2.8L V6 Motronic M2.9 FI, 172 HP (1992-93)
F * 2.8L V6 Motronic SFI, 172 HP (1994)
6 - Restraint System
4 * Electric Passive With Manual Lap
7-8 - Model
50 * Corrado
9 - VIN Check Digit
2 * Computer Selected Check Number
10 - Vehicle Model Year
L * 1990
M * 1991
N * 1992
P * 1993
R * 1994
11 - Assembly Plant
A * Ingolstadt
B * Brussel
E * Emden
G * Graz
H * Hannover
K * Osnabruk
M * Mexico
N * Neckarsulm
P * Brazil
S * Stuttgart
W * Wolfsburg
12-17 - Serial Number
* Sequential Production Number
MAINTENANCE SERVICE INFORMATION
SEVERE & NORMAL SERVICE DEFINITIONS
NOTE: Use the Severe Service schedule if the vehicle to be serviced
is operated under ANY (one or more) of these conditions:
Service is recommended at mileage intervals based on vehicle
operation. Service schedules are based on the following primary
operating conditions:
Normal Service
* Driven More Than 10 Miles Daily
* No Operating Conditions From Severe Service Schedule
Page 638 of 906

MAINTENANCE INFORMATION
Article Text (p. 3)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:48PM
Severe Service (Unique Driving Conditions)
* Short Trips In Freezing Temperatures
* Towing Or Heavily Loaded
* Severe Dust Conditions
* Hot Weather, Stop-And-Go Driving
* Extensive Idling
CAMSHAFT TIMING BELT
CAUTION: Failure to replace a faulty camshaft timing belt may result
in serious engine damage.
The condition of camshaft drive belts should always be
checked on vehicles which have more than 50,000 miles. Although some
manufacturers do not recommend belt replacement at a specified
mileage, others require it at 60,000-100,000 miles. A camshaft drive
belt failure may cause extensive damage to internal engine components
on most engines, although some designs do not allow piston-to-valve
contact. These designs are often called "Free Wheeling".
Many manufacturers changed their maintenance and warranty
schedules in the mid-1980's to reflect timing belt inspection and/or
replacement at 50,000-60,000 miles. Most service interval schedules in
this manual reflect these changes.
Belts or components should be inspected and replaced if any
of the following conditions exist:
* Cracks Or Tears In Belt Surface
* Missing, Damaged, Cracked Or Rounded Teeth
* Oil Contamination
* Damaged Or Faulty Tensioners
* Incorrect Tension Adjustment
Inspect camshaft timing belt condition every 20,000 miles.
Replace belt as necessary.
DRIVE BELT ROUTINGFig. 1: Drive Belt Tensioner Adjustment (VR6)
Courtesy of Volkswagen United States, Inc.
Page 643 of 906
MAINTENANCE INFORMATION
Article Text (p. 8)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:48PM
CAMSHAFT TIMING BELT SERVICEFig. 7: Aligning 1.8L Timing Marks (8-Valve)
Courtesy of Volkswagen United States, Inc.
NOTE: For more information on camshaft timing belt service refer to
the 1.8L 4-CYL 8-VALVE & 2.0L 4-CYL 16-VALVE
article in the ENGINE MECHANICAL section.
ATTACHING VAG 1551 SCAN TESTER