
VDC(diag)-26
Warning Light Illumination Pattern
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
4) When the VDC indicator light, VDC warning light and TCS OFF indicator light do not go off, check the com-
bination meter circuit or CAN communication circuit.
NOTE:
•Even though the ABS warning light does not go off after 1.5 seconds from ABS warning light illumination,
the ABS system operates normally when the warning light goes off while driving at approximately 12 km/h (7
MPH). However, the ABS system does not work while the ABS warning light is illuminated.
•It may take several minutes before VDC warning light and TCS OFF indicator light goes off if the vehicle
is parked under low temperature for a specified time. This is not defective because it is resulted from low en-
gine coolant temperature.
•With the vehicle jack-up/lift-up or set on free rollers, when the wheels lock or spin after starting the engine,
ABS warning light, VDC warning light and TCS OFF indicator light may illuminate because VDCCM&H/U de-
tects the abnormal conditions from ABS wheel speed sensors. In this case, this is not a malfunction. Perform
the clear memory mode.
B: VDC WARNING LIGHT, TCS OFF INDICATOR LIGHT AND VDC INDICATOR
LIGHT DO NOT COME ON
DETECTING CONDITION:
•Defective combination meter
•Defective CAN communication
TROUBLE SYMPTOM:
When the ignition switch is turned to ON (engine OFF), VDC indicator light, VDC warning light and TCS OFF
indicator light do not come on.
NOTE:
When pressing the TCS OFF switch for more than 10 seconds, the TCS OFF indicator light goes off and can-
not operate any more. When turning the ignition switch from OFF to ON, the OFF operation enabled status
is restored.
Step Check Yes No
1CHECK OTHER INDICATOR LIGHT.
Tu r n t h e i g n i t i o n s w i t c h t o O N .
Does other indicator light illu-
minate soon after “ON”.
Go to step 2.Perform the self-
diagnosis of com-
bination meter.
2CHECK VDCCM.
When the engine does not start, display the
current data of VDCCM using Subaru Select
Monitor.
Is “VDC warning light” output
set to “ON”?
Go to step 3.Replace the
VDCCM&H/U.
3CHECK LAN SYSTEM.
Perfor m the diagnosis for LAN system.
Tr o u b l e C o d e ( D T C ) . >
Is there any fault in LAN sys-
tem?
Pe r for m t h e d ia g -
nosis according to
DTC for LAN sys-
tem.
Go to step 4.
4CHECK COMBINATION METER.
Check the combination meter.
Is combination meter OK? Replace the
VDCCM&H/U.
Repair the combi-
nation meter
assembly.

VDC(diag)-34
List of Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
11.List of Diagnostic Trouble Code (DTC)
A: LIST
DTCDetailed
codeDisplay Content of diagnosis Reference target
C0021 4211FR wheel speed sensor
open line
Open line of the front
ABS wheel speed sen-
sor RH
nostic Procedure with Diagnostic Trouble Code
(DTC).>
C0022
4221FR wheel speed sensor
system
Fr o nt A B S w h e el sp e ed
sensor RH signal mal-
function
FUNCTION, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
4222 FR wheel sensor noiseFr o nt A B S w h e el sp e ed
sensor RH signal noise
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
C0023 4231FL wheel speed sensor
open line
Open line of the front
ABS wheel speed sen-
sor LH
nostic Procedure with Diagnostic Trouble Code
(DTC).>
C0024
4241FL wheel speed sensor
signal system
Fr o nt A B S w h e el sp e ed
sensor LH signal mal-
function
FUNCTION, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
4242 FL wheel sensor noiseFr o nt A B S w h e el sp e ed
sensor LH signal noise
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
C0025 4251RR wheel sensor open
line
Rear ABS wheel speed
sensor RH open line
nostic Procedure with Diagnostic Trouble Code
(DTC).>
C0026
4261RR wheel speed sen-
sor signal system
Rear ABS wheel speed
sensor RH signal mal-
function
FUNCTION, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
4262 RR wheel sensor noiseRear ABS wheel speed
sensor RH signal noise
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
C0027 4271RL wheel speed sensor
open line
Rear ABS wheel speed
sensor LH open line
nostic Procedure with Diagnostic Trouble Code
(DTC).>
C0028
4281RL wheel speed sensor
signal system
Rear ABS wheel speed
sensor LH signal mal-
function
FUNCTION, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
4282 RL wheel sensor noiseRear ABS wheel speed
sensor LH signal noise
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
C0031 4311FR hold valve malfunc-
tion
Fr o nt i nl e t s ol e no i d
valve RH malfunction in
VDCCM&H/U
VDCCM&H/U, Diagnostic Procedure with Diag-
nostic Trouble Code (DTC).>

VDC(diag)-38
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
12.Diagnostic Procedure with Diagnostic Trouble Code (DTC)
A: DTC C0021 FRONT ABS WHEEL SPEED SENSOR RH OPEN LINE
NOTE:
For the diagnostic procedure, refer to DTC C0027 REAR ABS WHEEL SPEED SENSOR LH OPEN LINE.
B: DTC C0023 FRONT ABS WHEEL SPEED SENSOR LH OPEN LINE
NOTE:
For the diagnostic procedure, refer to DTC C0027 REAR ABS WHEEL SPEED SENSOR LH OPEN LINE.
C: DTC C0025 REAR ABS WHEEL SPEED SENSOR RH OPEN LINE
NOTE:
For the diagnostic procedure, refer to DTC C0027 REAR ABS WHEEL SPEED SENSOR LH OPEN LINE.

VDC(diag)-39
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
D: DTC C0027 REAR ABS WHEEL SPEED SENSOR LH OPEN LINE
DTC DETECTING CONDITION:
•Faulty ABS wheel speed sensor (harness open line)
•Defective harness connector
TROUBLE SYMPTOM:
•ABS does not operate.
•VDC does not operate.
WIRING DIAGRAM:
26404127392543
B98
R249R232
R1
B97
R2
E
12121212B6B15
2842
B310VDCCM & H/U
TWISTED PAIR LINETWISTED PAIR LINE
TWISTED PAIR LINETWISTED PAIR LINE
REAR ABS WHEELSPEED SENSOR RH
FRONT ABS WHEELSPEED SENSOR RHFRONT ABS WHEELSPEED SENSOR LHREAR ABS WHEELSPEED SENSOR LH
B15
B6
R249
R232
VDC00370
920922
B310
1234
1516171819202122232425262728293031323334353637383940414245464344568910 11 12 13 147
B98
3412 8910 1112 13 14 15 16 17 18 19 20 21 22 23 2456 7
B97
1234 5678910 11 12 13 14 15 16 17 18 19 2012

VDC(diag)-40
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Step Check Yes No
1CHECK POOR CONTACT OF CONNECTOR.
Check if there is poor contact between
VDCCM&H/U and ABS wheel speed sensor.
Is there poor contact? Repair the con-
nector.
Go to step 2.
2CHECK HARNESS CONNECTOR BETWEEN
VDCCM&H/U AND ABS WHEEL SPEED
SENSOR.
1) Disconnect the connector (B310) from the
VDCCM&H/U.
2) Disconnect the connector from ABS wheel
speed sensor.
3) Measure the resistance between
VDCCM&H/U connector and ABS wheel
speed sensor connector.
Connector & terminal
DTC C0021
(B310) No. 42 — (B6) No. 1:
(B310) No. 28 — (B6) No. 2:
DTC C0023
(B310) No. 27 — (B15) No. 1:
(B310) No. 41 — (B15) No. 2:
DTC C0025
(B310) No. 40 — (R249) No. 1:
(B310) No. 26 — (R249) No. 2:
DTC C0027
(B310) No. 25 — (R232) No. 1:
(B310) No. 39 — (R232) No. 2:
Is the resistance less than 0.5
Ω?
Go to step 3.Repair the har-
ness connector
between
VDCCM&H/U and
ABS wheel speed
sensor.
3CHECK GROUND SHORT OF HARNESS.
Measure the resistance between VDCCM&H/U
connector and chassis ground.
Connector & terminal
DTC C0021
(B310) No. 28 — Chassis ground:
DTC C0023
(B310) No. 41 — Chassis ground:
DTC C0025
(B310) No. 26 — Chassis ground:
DTC C0027
(B310) No. 39 — Chassis ground:
Is the resistance more than 1
MΩ?
Go to step 4.Repair the har-
ness connector
between
VDCCM&H/U and
ABS wheel speed
sensor.
4CHECK ABS WHEEL SPEED SENSOR POW-
ER SUPPLY CIRCUIT.
1) Connect the VDCCM&H/U connector.
2) Turn the ignition switch to ON.
3) Measure the voltage between ABS wheel
speed sensor connector and chassis ground.
Connector & terminal
DTC C0021
(B6) No. 1 (+) — Chassis ground (–):
DTC C0023
(B15) No. 1 (+) — Chassis ground (–):
DTC C0025
(R249) No. 1 (+) — Chassis ground (–):
DTC C0027
(R232) No. 1 (+) — Chassis ground (–):
Is the voltage 8.5 — 13.5 V? Go to step 6.Go to step 5.

VDC(diag)-41
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
5CHECK THE VDCCM&H/U POWER SUPPLY
CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the VDCCM&H/U connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between VDCCM&H/
U connector terminals.
Connector & terminal
(B310) No. 1 (+) — (B310) No. 43 (–):
Is the voltage 10 — 15 V? Go to step 7.Check the genera-
tor, batter y and
VDCCM&H/U
power supply cir-
cuit.
6CHECK ABS WHEEL SPEED SENSOR SIG-
NAL.
1) Install the ABS wheel speed sensor.
2) Prepare an oscilloscope.
3) Check the ABS wheel speed sensor.
INSPECTION, Front ABS Wheel Speed Sen-
sor.>
Is the pattern the same wave-
for m as shown in the figure?
Go to step 7.Replace the ABS
wheel speed sen-
sor.
7CHECK THE VDCCM&H/U.
1) Connect all the connectors.
2) Erase the memory.
3) Perform the inspection mode.
Mode.>
4) Read the DTC.
Is the same DTC displayed? Replace the
VDCCM&H/U.
ule & Hydraulic
Control Unit
(VDCCM&H/U).>
Go to step 8.
8CHECK OTHER DTC DETECTION.Is any other DTC displayed? Perform the diag-
nosis according to
DTC.
It results from a
temporary noise
interference.
Step Check Yes No

VDC(diag)-42
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
E: DTC C0022 FRONT ABS WHEEL SPEED SENSOR RH SIGNAL NOISE
NOTE:
For the diagnostic procedure, refer to DTC C0028 “REAR ABS WHEEL SPEED SENSOR LH SIGNAL MAL-
FUNCTION”.
F: DTC C0024 FRONT ABS WHEEL SPEED SENSOR LH SIGNAL NOISE
NOTE:
For the diagnostic procedure, refer to DTC C0028 “REAR ABS WHEEL SPEED SENSOR LH SIGNAL MAL-
FUNCTION”.
G: DTC C0026 REAR ABS WHEEL SPEED SENSOR RH SIGNAL NOISE
NOTE:
For the diagnostic procedure, refer to DTC C0028 “REAR ABS WHEEL SPEED SENSOR LH SIGNAL MAL-
FUNCTION”.
H: DTC C0028 REAR ABS WHEEL SPEED SENSOR LH SIGNAL NOISE
NOTE:
For the diagnostic procedure, refer to DTC C0028 “REAR ABS WHEEL SPEED SENSOR LH SIGNAL MAL-
FUNCTION”.
I: DTC C0022 FRONT ABS WHEEL SPEED SENSOR RH SIGNAL MALFUNC-
TION
NOTE:
For the diagnostic procedure, refer to DTC C0028 “REAR ABS WHEEL SPEED SENSOR LH SIGNAL MAL-
FUNCTION”.
J: DTC C0024 FRONT ABS WHEEL SPEED SENSOR LH SIGNAL MALFUNC-
TION
NOTE:
For the diagnostic procedure, refer to DTC C0028 “REAR ABS WHEEL SPEED SENSOR LH SIGNAL MAL-
FUNCTION”.
K: DTC C0026 REAR ABS WHEEL SPEED SENSOR RH SIGNAL MALFUNC-
TION
NOTE:
For the diagnostic procedure, refer to DTC C0028 “REAR ABS WHEEL SPEED SENSOR LH SIGNAL MAL-
FUNCTION”.

VDC(diag)-43
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
L: DTC C0028 REAR ABS WHEEL SPEED SENSOR LH SIGNAL MALFUNC-
TION
DTC DETECTING CONDITION:
•Defective ABS wheel speed sensor signal (noise, irregular signal, etc.)
•Defective harness connector
TROUBLE SYMPTOM:
•ABS does not operate.
•VDC does not operate.
WIRING DIAGRAM:
26404127392543
B98
R249R232
R1
B97
R2
E
12121212B6B15
2842
B310VDCCM & H/U
TWISTED PAIR LINETWISTED PAIR LINE
TWISTED PAIR LINETWISTED PAIR LINE
REAR ABS WHEELSPEED SENSOR RH
FRONT ABS WHEELSPEED SENSOR RHFRONT ABS WHEELSPEED SENSOR LHREAR ABS WHEELSPEED SENSOR LH
B15
B6
R249
R232
VDC00370
920922
B310
1234
1516171819202122232425262728293031323334353637383940414245464344568910 11 12 13 147
B98
3412 8910 1112 13 14 15 16 17 18 19 20 21 22 23 2456 7
B97
1234 5678910 11 12 13 14 15 16 17 18 19 2012