1995 AUDI A4 check engine light

01-133

Output on GST and/or
on VAG 1551 scan tool
Possible malfunction cause

Malfunction repair
P1506 / 17914
CTP Switch does not
Open
Short to Ground Harness connector on Throttle Position (TP)
sensor -G69- and Closed Throttle (CTP) switch -
F60- loose or corroded due to moisture in the
harness connector

- Check harness connector for tight fit
and contact corrosion, if necessary
reconnect and/or clean

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
MIL Status:
MIL lights up
immediately Closed Throttle (CTP) switch -F60- in the
Throttle Position Sensor does not open or is
faulty

- Check and adjust idle switch page 24
-73

Note:
Malfunction P0120 /
16504 is also stored Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
For troubleshooting
Display groups 000,
002, 004
Engine Control Module (ECM) -J192- faulty

- Replace and code engine control
module page 01
-265
erase DTC
memory and test drive check DTC
memory
Note:
Pa
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) - Multi
port Fuel In
jection
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-134

Output on GST and/or
on VAG 1551 scan tool
Possible malfunction cause

Malfunction repair
P1509 / 17917
IAC Circ.
Electrical Malfunction Harness connector on Idle Air Control
(IAC) valve -N71- loose or corroded due to
moisture in the harness connector

- Check harness connector for tight fit and
contact corrosion, if necessary reconnect
and/or clean, installation location page 24
-
1

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after test
drive, check DTC memory again
MIL Status:
MIL lights up
immediately
Wiring connection to Idle Air Control
(IAC) valve -N71- faulty or valve -N71-
faulty

- Check Idle Air Control (IAC) valve -N71-
page 24
-37


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after test
drive, check DTC memory again
For troubleshooting
Display group 018
Engine Control Module (ECM) -J192-
faulty

- Replace and code engine control module
page 01
-265
erase DTC memory and test
drive check DTC memory
Note:
If a malfunction is recognized in the electrical circuit, both power output stages ("+" and "-" output) are switched off. The Idle
Air Control (IAC) -N71- has no power and opens the limp home cross section.
Pa
ge 182 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-135

Output on GST and/or
on VAG 1551 scan tool
Possible malfunction cause

Malfunction repair
P1510 / 17918
IAC Circ.
Short to B+ Harness connector for Idle Air Control
(IAC) valve -N71- loose or corroded due to
moisture in the harness connector

- Check harness connector for tight fit and
contact corrosion, if necessary reconnect
and/or clean, installation location page 24
-
1

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after
test drive, check DTC memory again
MIL Status:
MIL lights up
immediately
Wiring connection to Idle Air Control
(IAC) valve -N71- faulty or valve -N71-
faulty

- Check Idle Air Control (IAC) valve -N71-
page 24
-37


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after
test drive, check DTC memory again
For troubleshooting
Display group 018
Engine Control Module (ECM) -J192-
faulty

- Replace and code engine control module
page 01
-265
erase DTC memory and test
drive check DTC memory
Note:
If a malfunction is recognized in the electrical circuit, both power output stages ("+" and "-" output) are switched off. The idle
stabilizer valve -N71- has no power and opens the limp home cross section.
Pa
ge 183 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-138

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P1600 / 18008
Power Supply (B+)
Terminal 15
Low Voltage Battery discharged or faulty

Repair Manual, Electrical
Equipment, Repair Group 27
- Check and charge battery

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
MIL Status:
Malfunction not displayed
by MIL Bad ground connection to Engine Control
Module (ECM) -J192-

- Check voltage supply to the Engine
Control Module (ECM) -J192-
page 28
-27


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again

Excessive current draw with ignition off (e.g.
because of luggage compartment light on
continuously, etc.)

- Carry out holding current test. The
holding current must be greater than
50 mA
For troubleshooting
Display group 001
Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
Pa
ge 186 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-140

Output on GST
and/or on VAG
1551 scan tool Possible malfunction cause

Malfunction repair
P1602 / 18010
Power Supply (B+)
Terminal 30
Low Voltage The malfunction is set when the
battery/control module is disconnected
with ignition on or with a starting attempt
with ignition/control module
disconnected

- The malfunction is erased after the second engine
start if there is sufficient supply voltage. Therefore,
start car after battery/control module is
disconnected; shut off and start car again, then
check DTC memory again.

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after test drive,
check DTC memory again
MIL Status:
MIL lights up
immediately Poor ground connection between
battery and body

- Check ground cable for good contact on battery
terminal and check the threaded connection on the
body

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after test drive,
check DTC memory again

Break in the wiring connection
between battery and Engine Control
Module (ECM) -J192-

- Check voltage supply of engine control module
page 28
-27


Malfunction cause found: Yes

- Erase DTC memory, test drive and after test drive,
Pa
ge 189 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-142

Output on GST and/or
on VAG 1551 scan tool
Possible malfunction cause

Malfunction repair
P1611 / 18019
MIL Call-up Circ./
Transm.Control Module
Short to Ground Wiring connection between Engine
Control Module (ECM) -J192- and
Transmission Control Module (TCM) -J217-
faulty

- Check MIL wiring from Transmission
Control Module (TCM) -J217- page 24
-
105


Malfunction cause found: Yes
No

- Erase DTC memory, test drive, after test
drive check DTC memory again
MIL Status:
MIL lights up
immediately Transmission Control Module (TCM) -
J217- faulty

Repair Manual, 5 Spd. Automatic
Transmission 01V On Board Diagnostic (OBD), Repair Group 01
- Replace Transmission Control Module
(TCM) -J217-

Malfunction cause found: Yes
No

- Erase DTC memory, test drive, after test
drive check DTC memory again
For troubleshooting
Display group 027
Engine Control Module (ECM) -J192-
faulty

- Replace and code ECM -J192- page 01
-265
erase DTC memory and take
test drive check DTC memory
Notes:
Pa
ge 193 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-144

Output on GST and/or
on VAG 1551 scan tool
Possible malfunction cause

Malfunction repair
P1613 / 18021
MIL Call-up Circ.Open
Short to B+ Wiring connection between Engine
Control Module (ECM) -J192- and
Transmission Control Module (TCM) -J217-
faulty

- Check MIL wiring from Transmission
Control Module (TCM) -J217- page 24
-
105


Malfunction cause found: Yes
No

- Erase DTC memory, test drive, after test
drive check DTC memory again
MIL Status:
MIL lights up
immediately
Transmission Control Module (TCM) -
J217- faulty

Repair Manual, 5 Spd.
Automatic
Transmission 01V On Board Diagnostic (OBD), Repair Group 01
- Replace ABS control module -J104-

Malfunction cause found: Yes
No

- Erase DTC memory, take test drive, after
test drive check DTC memory again
For troubleshooting
Display group 027
Engine Control Module (ECM) -J192-
faulty

- Replace and code ECM -J192- page 01
-265
erase DTC memory and take
test drive check DTC memory
Notes:

This malfunction can only occur in connection with an automatic transmission.
Pa
ge 196 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1