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Volkswagen New Beetle. Manual - part 1779

DTC P0102/16486
MAF Sensor Signal (G70) - Open Circuit/Short To B +

DTC P0103/16487
MAF Sensor Signal (G70) - Open Circuit/Short To Ground

DTC P1144/17552
MAF Sensor Signal (G70) - Open Circuit/Short To Ground

DTC P1145/17553
MAF Sensor Signal (G70) - Short To B+

DTC P1146/17554
MAF Sensor Signal (G70) - Supply Voltage Too High/Low

Possible Effects

Possible effects are black smoke and/or lack of power.

Test Procedures

1. Check air induction system for leaks. If problem exists, repair as necessary. If problem does not exist, go

to next step.

2. Check EGR system for damaged components, disconnected connectors and leaks. If problem exists,

repair as necessary. If problem does not exist, go to next step.

3. Turn ignition off. Disconnect MAF sensor harness connector. Turn ignition on. Measure voltage between

ground and terminal No. 2 at MAF sensor harness connector. See Fig. 13 . Voltage should be at least 11.5
volts. Measure voltage between terminals No. 2 and 3 at MAF sensor harness connector. Voltage should
be at least 11.5 volts. Measure voltage between ground and terminal No. 4 at MAF sensor harness
connector. Voltage should be approximately 5 volts. Measure voltage between terminals No. 3 and 4 at
MAF sensor harness connector. Voltage should be approximately 5 volts. If voltages are as specified,
replace MAF sensor. If any voltage is not as specified, go to next step.

4. Turn ignition off. Disconnect Engine Control Module (ECM) harness connector. Connect VAG 1598/31

test box to ECM harness connector, leave ECM disconnected, see CONNECTING VAG TEST BOX .

NOTE:

For connector terminal wire colors, see appropriate WIRING DIAGRAM under
ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS. For component
locations, see COMPONENT LOCATIONS .

NOTE:

Before replacing any component, ensure all connectors at component and ECM
are clean and tight. After making any repairs, disconnect ECM harness
connector for 10 seconds, connect ECM harness connector and retest system.
It is necessary to generate an ECM readiness code if ECM memory is cleared,
battery voltage is disconnected or ECM is disconnected.

2003 Volkswagen New Beetle GLS

2002-2004 ENGINE PERFORMANCE Self-Diagnostics - 1.9L Turbo Diesel - Beetle, Golf & Jetta (Engine Code ALH)

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Page 28

Measure resistance between terminal No. 2 at MAF sensor harness connector and socket No. 1 at test box.
Measure resistance between terminal No. 2 at MAF sensor harness connector and socket No. 2 at test box.
Measure resistance between terminal No. 3 at MAF sensor harness connector and socket No. 49 at test
box. Measure resistance between terminal No. 4 at MAF sensor harness connector and socket No. 30 at
test box. Measure resistance between terminal No. 5 at MAF sensor harness connector and socket No. 68
at test box. Resistance should be a maximum of 1.5 ohms for each reading. If resistance measurements
are okay, go to next step. If any resistance measurement is not okay, repair circuit(s) as necessary. After
repairs, erase DTC memory. See CLEARING DIAGNOSTIC TROUBLE CODES (FUNCTION 05)
under SELF DIAGNOSTIC SYSTEM. Verify repair. Test is complete. Perform ECM relearn procedure.
See TEST DRIVE RELEARN PROCEDURE .

6. Measure resistance between terminals No. 2, 3, 4 and 5 at MAF sensor harness connector. All resistances

should be infinite between each circuit. If resistances are as specified, go to next step. If any resistance is
not as specified, repair shorted circuits between MAF sensor and ECM. After repairs, erase DTC
memory. See CLEARING DIAGNOSTIC TROUBLE CODES (FUNCTION 05) under SELF
DIAGNOSTIC SYSTEM. Verify repair. Test is complete. Perform ECM relearn procedure. See TEST
DRIVE RELEARN PROCEDURE .

7. Measure resistance between ground and terminals No. 2, 3, 4 and 5 at MAF sensor harness connector. All

resistances should be infinite. If resistances are as specified, go to next step. If any resistance is not as
specified, repair shorted circuits between MAF sensor and ECM. After repairs, erase DTC memory. See
CLEARING DIAGNOSTIC TROUBLE CODES (FUNCTION 05) under SELF DIAGNOSTIC
SYSTEM. Verify repair. Test is complete. Perform ECM relearn procedure. See TEST DRIVE
RELEARN PROCEDURE .

8. Measure resistance between positive battery terminal and terminals No. 3, 4 and 5 at MAF sensor harness

connector. All resistances should be infinite. If resistances are as specified, replace ECM. After repairs,
erase DTC memory. See CLEARING DIAGNOSTIC TROUBLE CODES (FUNCTION 05) under
SELF DIAGNOSTIC SYSTEM. Verify repair. Test is complete. Perform ECM relearn procedure. See
TEST DRIVE RELEARN PROCEDURE .

9. If any resistance is not as specified, repair short to voltage in wiring between MAF sensor and ECM.

After repairs, erase DTC memory. See CLEARING DIAGNOSTIC TROUBLE CODES
(FUNCTION 05) under SELF DIAGNOSTIC SYSTEM. Verify repair. Test is complete. Perform ECM
relearn procedure. See TEST DRIVE RELEARN PROCEDURE .

NOTE:

Test box socket numbers correspond to ECM pin numbers.

2003 Volkswagen New Beetle GLS

2002-2004 ENGINE PERFORMANCE Self-Diagnostics - 1.9L Turbo Diesel - Beetle, Golf & Jetta (Engine Code ALH)

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Fig. 13: Identifying MAF Sensor Harness Connector Terminals
Courtesy of VOLKSWAGEN UNITED STATES, INC.

DTC P0105/16489, DTC P0106/16490, DTC P0107/16491, DTC P0108/16492, DTC P1155/17563, DTC
P1156/17564, DTC P1157/17565 & DTC P1158/17566

Code Definition

DTC P0105/16489
MAP Sensor Signal (G71) - Open Circuit/Short To Ground

DTC P0106/16490
MAP Sensor Signal (G71) - Open Circuit/Short To Ground

DTC P010716491
MAP Sensor Signal (G71) - Open Circuit/Short To Ground

DTC P0108/16492
MAP Sensor Signal (G71) - Open Circuit/Short To Ground

2003 Volkswagen New Beetle GLS

2002-2004 ENGINE PERFORMANCE Self-Diagnostics - 1.9L Turbo Diesel - Beetle, Golf & Jetta (Engine Code ALH)

Helpmelearn Repair Manuals

Wednesday, December 14, 2005 8:48:21 AM

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DTC P1155/17563
MAP Sensor Signal (G71) - Short To B+

DTC P1156/17564
MAP Sensor Signal (G71) - Open Circuit/Short To Ground

DTC P1157/17565
MAP Sensor Signal (G71) - Supply Voltage

DTC P1158/17566
MAP Sensor Signal (G71) - Implausible Signal

Possible Effects

Possible effects are lack of power and/or increased emissions.

Test Procedures

1. Connect turbocharger test unit VAG 1397A by connecting into a manifold vacuum line. Let engine idle.

Connect scan tool. See Fig. 1 . Press keys "0" and "1" for address word "Engine Electronics", press keys
"0" and "8" for "Read measuring value block" and enter by pressing "Q" key. Press keys "0", "1" and "0"
for display group "10" and enter by pressing "Q" key.

NOTE:

For connector terminal wire colors, see appropriate WIRING DIAGRAM under
ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS. For component
locations, see Fig. 14 .

NOTE:

If a test ends with ECM replacement. Before replacing ECM be certain that, all
wiring, power and ground supplies are okay. See ENGINE PERFORMANCE in
SYSTEM WIRING DIAGRAMS article in ELECTRICAL and ECM GROUND &
VOLTAGE SUPPLY .

CAUTION: Turbocharger test unit must be set to measuring range " I" (absolute

pressure). Turbocharger test unit is used to provide an independent
figure for comparison. If display in field 2 (BARO Sensor -F96) and
display in field 3 (MAP Sensor -G71) are within 30 mbar of each other,
check turbocharger test unit for miss calibration /faults and leaks.

NOTE:

Barometric sensor (F96) is an integral part of ECM.

2003 Volkswagen New Beetle GLS

2002-2004 ENGINE PERFORMANCE Self-Diagnostics - 1.9L Turbo Diesel - Beetle, Golf & Jetta (Engine Code ALH)

Helpmelearn Repair Manuals

Wednesday, December 14, 2005 8:48:21 AM

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