Infiniti I30 (A33). Manual — part 210

SEF243Y

SEF175Y

PROCEDURE FOR MALFUNCTION D

NHEC0054S04

CAUTION:

Always drive vehicle at a safe speed.

With CONSULT-II

NHEC0054S0402

1)

Turn ignition switch “ON”.

2)

Start engine and warm it up to normal operating temperature.
If engine cannot be started, go to “Diagnostic Procedure”,
EC-157.

3)

Select “DATA MONITOR” mode with CONSULT-II.

4)

Check the voltage of MAS AIR/FL SE with “DATA MONITOR”.

5)

Increases engine speed to about 4,000 rpm.

6)

Monitor the linear voltage rise in response to engine speed
increases.
If NG, go to “Diagnostic Procedure”, EC-157.
If OK, go to following step.

7)

Maintain the following conditions for at least 10 consecutive
seconds.

ENG SPEED

More than 2,000 rpm

THRTL POS SEN

More than 3V

Selector lever

Suitable position

Driving location

Driving vehicle uphill (Increased engine load)
will help maintain the driving conditions
required for this test.

8)

If 1st trip DTC is detected, go to “Diagnostic Procedure”,
EC-157.

SEF534P

Overall Function Check

NHEC0055

PROCEDURE FOR MALFUNCTION D

NHEC0055S01

Use this procedure to check the overall function of the mass air flow
sensor circuit. During this check, a 1st trip DTC might not be con-
firmed.

With GST

NHEC0055S0101

1)

Start engine and warm it up to normal operating temperature.

2)

Select “MODE 1” with GST.

3)

Check the mass air flow sensor signal with “MODE 1”.

4)

Check for linear mass air flow sensor signal value rise in
response to increases to about 4,000 rpm in engine speed.

5)

If NG, go to “Diagnostic Procedure”, EC-157.

GI

MA

EM

LC

FE

AT

AX

SU

BR

ST

RS

BT

HA

SC

EL

IDX

DTC P0100 MASS AIR FLOW SENSOR (MAFS)

DTC Confirmation Procedure (Cont’d)

EC-155

Wiring Diagram

NHEC0056

MEC799C

SEF650XB

DTC P0100 MASS AIR FLOW SENSOR (MAFS)

Wiring Diagram

EC-156

Diagnostic Procedure

NHEC0057

1

INSPECTION START

Which malfunction (A, B, C, D or E) is duplicated?

MTBL0373

Type I or Type II

Type I

©

GO TO 3.

Type II

©

GO TO 2.

2

CHECK INTAKE SYSTEM

Check the following for connection.

I

Air duct

I

Vacuum hoses

I

Intake air passage between air duct to intake manifold collector

OK or NG

OK

©

GO TO 3.

NG

©

Reconnect the parts.

3

RETIGHTEN GROUND SCREWS

1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.

SEF255X

©

GO TO 4.

GI

MA

EM

LC

FE

AT

AX

SU

BR

ST

RS

BT

HA

SC

EL

IDX

DTC P0100 MASS AIR FLOW SENSOR (MAFS)

Diagnostic Procedure

EC-157

4

CHECK MAFS POWER SUPPLY CIRCUIT

1. Disconnect mass air flow sensor (MAFS) harness connector.

SEF256X

2. Turn ignition switch “ON”.
3. Check voltage between MAFS terminals 2, 4 and ground with CONSULT-II or tester.

SEF297X

OK or NG

OK

©

GO TO 6.

NG

©

GO TO 5.

5

DETECT MALFUNCTIONING PART

Check the following.

I

Harness for open or short between ECM relay and mass air flow sensor

I

Harness for open or short between mass air flow sensor and ECM

©

Repair harness or connectors.

6

CHECK MAFS GROUND CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch “OFF”.
2. Disconnect ECM harness connector.
3. Check harness continuity between MAFS terminal 3 and ECM terminal 73.

Refer to Wiring Diagram.

Continuity should exist.

4. Also check harness for short to ground and short to power.

OK or NG

OK

©

GO TO 7.

NG

©

Repair open circuit or short to ground or short to power in harness or connectors.

DTC P0100 MASS AIR FLOW SENSOR (MAFS)

Diagnostic Procedure (Cont’d)

EC-158