Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 274

EN(H4DOTC)(diag)-320

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

CHECK HARNESS BETWEEN ECM AND
TUMBLE GENERATOR VALVE ASSEMBLY
LH CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
tumble generator valve assembly LH.
3) Measure the resistance of harness between
ECM connector and tumble generator valve
assembly LH connector.

Connector & terminal

(B134) No. 23 — (E51) No. 5:
(B134) No. 24 — (E51) No. 4:

Is the resistance less than 1 Ω? Go to step

Repair the harness
and connector.
NOTE:

In this case, repair
the following item:
• Open circuit in
harness between
ECM

connector

and tumble gener-
ator valve assem-
bly LH connector
• Poor contact of
coupling connector

CHECK HARNESS BETWEEN ECM AND
TUMBLE GENERATOR VALVE ASSEMBLY
LH CONNECTOR.
Measure the resistance between ECM connec-
tor and chassis ground.

Connector & terminal

(B134) No. 23 — Chassis ground:
(B134) No. 24 — Chassis ground:

Is the resistance 1 MΩ or
more?

Go to step

Repair the short
circuit to ground in
harness between
ECM connector
and tumble gener-
ator valve assem-
bly LH connector.

CHECK FOR POOR CONTACT.
Check for poor contact of tumble generator
valve assembly LH connector.

Is there poor contact of the tum-
ble generator valve assembly
LH connector?

Repair the poor
contact of tumble
generator valve
assembly LH con-
nector.

Replace the tum-
ble generator valve
assembly LH.
<Ref. to FU(STI)-
48, Tumble Gener-
ator Valve Assem-
bly.> <Ref. to
FU(w/o STI)-48,
Tumble Generator
Valve Assembly.>

EN(H4DOTC)(diag)-321

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DX:DTC P2012 INTAKE MANIFOLD RUNNER CONTROL CIRCUIT LOW

(BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-225, DTC P2012 INTAKE MANIFOLD RUNNER CON-

TROL CIRCUIT LOW (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>
CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-63,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-49, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine electrical system, without SI-DRIVE <Ref. to WI-32, WITHOUT SI-DRIVE, WIRING DIAGRAM,

Engine Electrical System.>

• Engine electrical system, with SI-DRIVE <Ref. to WI-48, WITH SI-DRIVE, WIRING DIAGRAM, Engine

Electrical System.>

ECM

B21

A25

D11

A26

A23

A19

D10

A29

A24

1 2 3

4 5

E51

E55

B134

B137

E55

E51

22 23

11 12 13 14 15

24 25

16 17

18 19 20 21

28 29

30 31

B137

22 23

11 12 13 14 15

26 27

16 17

18 19 20 21

33 34

30 31

B134

B21

1 2 3 4 5 6 7 8 9 10 11

12 13 14 15 16 17 18 19 20 21 22
23 24 25 26 27 28 29 30 31 32 33

34 35
42 43

36 37 38 39

48 49 50 51 52 53 54

40 41

44 45

46 47

EN-09253

TUMBLE GENERATOR

VALVE ACTUATOR LH

TUMBLE GENERATOR

VALVE ACTUATOR RH

EN(H4DOTC)(diag)-322

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

CHECK HARNESS BETWEEN ECM AND
TUMBLE GENERATOR VALVE ASSEMBLY
LH CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the voltage between ECM connec-
tor and chassis ground.

Connector & terminal

(B134) No. 23 (+) — Chassis ground (–):
(B134) No. 24 (+) — Chassis ground (–):

Is the voltage 5 V or more?

Repair the short
circuit to power in
harness between
ECM connector
and tumble gener-
ator valve assem-
bly LH connector.

Replace the tum-
ble generator valve
assembly LH.
<Ref. to FU(STI)-
48, Tumble Gener-
ator Valve Assem-
bly.> <Ref. to
FU(w/o STI)-48,
Tumble Generator
Valve Assembly.>

EN(H4DOTC)(diag)-323

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DY:DTC P2016 TUMBLE GENERATED VALVE POSITION SENSOR 1 CIRCUIT

LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition