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Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual - part 542

VDC(diag)-67

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Y: DTC C0042 POWER SUPPLY VOLTAGE FAILURE

DTC DETECTING CONDITION:

Improper VDCCM&H/U power supply voltage

TROUBLE SYMPTOM:

• ABS does not operate.

• EBD may not operate.

• VDC does not operate.
NOTE:

Warning lights go off if voltage returns.

WIRING DIAGRAM:

Vehicle Dynamics Control System <Ref. to WI-67, Vehicle Dynamics Control System.>

MAIN SBF

SBF-6

No.33

B310

VDCCM & H/U

BATTERY

GENERATOR

IGNITION

SWITCH

B310

4 5 6 7 8 9

26 27 28 29 30

2 3

31 32 33 34 35 36

10 11

14 15 16 17 18 19

37 38 39 40

12 13

41 42 43 44 45 46

20 21

23 24

VDC00463

VDC(diag)-68

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Step

Check

Yes

CHECK GENERATOR.
1) Start the engine.
2) Run the engine at idle after warming up.
3) Measure the voltage between generator ter-
minal B and chassis ground.

Terminals

Generator terminal B (+) — Chassis
ground (–):

Is the voltage 10 — 15 V?

Go to step

Repair the genera-
tor.

CHECK BATTERY TERMINAL.
Turn the ignition switch to OFF.

Are the positive and negative
battery terminals clamped
tightly?

Go to step

Tighten the termi-
nal.

CHECK VDCCM&H/U INPUT VOLTAGE.
1) Disconnect the connector from the
VDCCM&H/U.
2) Run the engine at idle.
3) Operate devices such as headlights, air
conditioner, defogger, etc. which produce an
electrical load.
4) Measure the voltage between VDCCM&H/U
connector and chassis ground.

Connector & terminal

(B310) No. 28 (+) — Chassis ground (–):

Is the voltage 10 — 15 V?

Go to step

Repair the power
supply circuit.

CHECK VDCCM&H/U GROUND CIRCUIT.
1) Turn the ignition switch to OFF.
2) Measure the resistance between
VDCCM&H/U connector and chassis ground.

Connector & terminal

(B310) No. 25 — Chassis ground:

Is the resistance less than 10

Ω?

Go to step

Repair the
VDCCM&H/U
ground harness.

CHECK POOR CONTACT OF CONNEC-
TORS.

Is there poor contact of connec-
tor between generator, battery
and VDCCM&H/U?

Repair the connec-
tor.

Go to step

CHECK VDCCM&H/U.
1) Connect all connectors.
2) Clear the memory. <Ref. to VDC(diag)-27,
Clear Memory Mode.>
3) Perform the Inspection Mode. <Ref. to
VDC(diag)-26, Inspection Mode.>
4) Read the DTC.

Is the same DTC displayed?

Replace the
VDCCM only.
<Ref. to VDC-12,
REPLACEMENT,
VDC Control Mod-
ule and Hydraulic
Control Unit
(VDCCM&H/U).>

Go to step

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC. <Ref. to
VDC(diag)-48, List
of Diagnostic Trou-
ble Code (DTC).>

Temporary poor
contact occurs.

VDC(diag)-69

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Z: DTC C0045 INCORRECT VDC CONTROL MODULE SPECIFICATIONS

DTC DETECTING CONDITION:

Different control module specification

TROUBLE SYMPTOM:

• ABS does not operate.

• VDC does not operate.
NOTE:

When parameter selection for VDCCM is improper, this DTC may be memorized.

Step

Check

Yes

CHECK VDCCM REPLACEMENT HISTORY. Is there history of VDCCM

replacement by itself?

Go to step

CHECK VDCCM IDENTIFICATION SYMBOL.
Check the identification symbol of the seal
attached on the side of the VDCCM. <Ref. to
VDC-2, SPECIFICATION, General Descrip-
tion.>

Is the identification symbol cor-
rect?

Go to step

Replace the
VDCCM only.
<Ref. to VDC-12,
REPLACEMENT,
VDC Control Mod-
ule and Hydraulic
Control Unit
(VDCCM&H/U).>

CHECK VDCCM&H/U IDENTIFICATION
SYMBOL.
Check the identification symbol stamped on the
upper part of the H/U. <Ref. to VDC-2, SPECI-
FICATION, General Description.>

Is the identification symbol cor-
rect?

Go to step

Replace the
VDCCM&H/U.
<Ref. to VDC-8,
VDC Control Mod-
ule and Hydraulic
Control Unit
(VDCCM&H/U).>

CHECK PARAMETER SELECTED IN VDC-
CM.
<Ref. to VDC(diag)-21, PARAMETER CHECK,
OPERATION, Subaru Select Monitor.>

Does the parameter registered
in the VDCCM match the rele-
vant vehicle?

Go to step

Select and register
the correct param-
eter. <Ref. to
VDC(diag)-21,
PARAMETER
SELECTION,
OPERATION, Sub-
aru Select Moni-
tor.>

CHECK ECM SPECIFICATION.
Check the ECM specification.

Is the specification of ECM
same as vehicle specification?

Go to step

Replace the ECM.
<Ref. to FU(STI)-
59, Engine Control
Module (ECM).>
<Ref. to FU(w/o
STI)-57, Engine
Control Module
(ECM).>

Is the same DTC displayed?

Replace the
VDCCM only.
<Ref. to VDC-12,
REPLACEMENT,
VDC Control Mod-
ule and Hydraulic
Control Unit
(VDCCM&H/U).>

Go to step

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC. <Ref. to
VDC(diag)-48, List
of Diagnostic Trou-
ble Code (DTC).>

It results from a
temporary noise
interference.

VDC(diag)-70

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

AA:DTC C0047 CAN COMMUNICATION

DTC DETECTING CONDITION:

CAN communication line circuit is open or shorted.

TROUBLE SYMPTOM:

• ABS does not operate.

• VDC does not operate.

Step

Check

Yes

CHECK LAN SYSTEM.
Perform the diagnosis for LAN system. <Ref. to
LAN(diag)-2, Basic Diagnostic Procedure.>

Is there any fault in LAN sys-
tem?

Perform the diag-
nosis according to
DTC for LAN sys-
tem. <Ref. to
LAN(diag)-32, List
of Diagnostic Trou-
ble Code (DTC).>

Go to step

CHECK POOR CONTACT OF CONNEC-
TORS.

Is there poor contact of
VDCCM&H/U connector?

Repair the connec-
tor.

Go to step

CHECK OUTPUT OF STEERING ANGLE
SENSOR WITH SUBARU SELECT MONI-
TOR.
1) Select “Current Data Display & Save” on the
Subaru Select Monitor. <Ref. to VDC(diag)-19,
READ CURRENT DATA, OPERATION, Subaru
Select Monitor.>
2) Check the «Steer Angle Sensor Op».

Does the output signal change? Go to step

Check output of
the steering angle
sensor. <Ref. to
VDC(diag)-88,
DTC C0071
STEER ANGLE
SENSOR OP,
Diagnostic Proce-
dure with Diagnos-
tic Trouble Code
(DTC).>

CHECK OUTPUT OF YAW RATE & G SEN-
SOR WITH SUBARU SELECT MONITOR.
1) Select “Current Data Display & Save” on the
Subaru Select Monitor. <Ref. to VDC(diag)-19,
READ CURRENT DATA, OPERATION, Subaru
Select Monitor.>
2) Check the «Yaw Rate Sensor Output».

Does the output signal change? Go to step

Check output of
the yaw rate & G
sensor. <Ref. to
VDC(diag)-98,
DTC C0072 YAW
RATE SENSOR
COMMUNICA-
TION, Diagnostic
Procedure with
Diagnostic Trouble
Code (DTC).>

Is the same DTC displayed?

Replace the
VDCCM only.
<Ref. to VDC-12,
REPLACEMENT,
VDC Control Mod-
ule and Hydraulic
Control Unit
(VDCCM&H/U).>

Temporary poor
contact occurs.

Content .. 540 541 542 543 ..