Page 2034 of 3342
B2M0488
: Is the value fixed between 0.2 and 0.4 V in
function mode F13?
: Go to step10Q4.
: Replace rear oxygen sensor.
OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
OBD0707C
10Q4CHECK HARNESS BETWEEN REAR
OXYGEN SENSOR AND ECM CONNEC-
TOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from rear oxygen sensor.
3) Turn ignition switch to ON.
4) Measure voltage between rear oxygen sensor harness
connector and engine ground or chassis ground.
: Connector & terminal
2200 cc California spec. vehicles
(B19) No. 4 (+)—Engine ground ( ):
Except 2200 cc California spec. vehicles
(T6) No. 4 (+)—Chassis ground ( ):
Is the voltage more than 0.2 V?
: Replace rear oxygen sensor.
: Repair harness and connector.
NOTE:
In this case, repair the following:
Open circuit in harness between rear oxygen sensor and
ECM connector
Poor contact in rear oxygen sensor connector
Poor contact in ECM connector
Poor contact in rear oxygen sensor connecting harness
connector (Except 2200 cc California spec. vehicles)
10Q5
CHECK EXHAUST SYSTEM.
: Is there a fault in exhaust system?
NOTE:
Check the following items.
Loose installation of portions
Damage (crack, hole etc.) of parts
Looseness and ill fitting of parts between front oxygen
sensor and rear oxygen sensor
: Repair or replace faulty parts.
: Replace rear oxygen sensor.
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10S1
CHECK DTC P0135 ON DISPLAY.
: Does the Subaru select monitor or OBD-II
general scan tool indicate DTC P0141 and
P0135 at the same time?
: Go to next step 1).
: Go to step10S2.
B2M0553A
1) Turn ignition switch to OFF.
2) Disconnect connector from ECM.
3) Measure resistance of harness between ECM connec-
tor and chassis ground.
: Connector & terminal
(B84) No. 42—Chassis ground:
Is the resistance less than 5Ω?
: Repair poor contact in ECM connector.
: Repair harness and connector.
NOTE:
In this case, repair the following:
Open circuit in harness between ECM and coupling con-
nector (B22)
Open circuit in harness between coupling connector
(B22) and engine grounding terminal
Poor contact in rear oxygen sensor connector
Poor contact in rear oxygen sensor connecting harness
connector (B19)
Poor contact in coupling connector (B22)
OBD0145A
10S2CONNECT SUBARU SELECT MONITOR
OR THE OBD-II GENERAL SCAN TOOL,
AND READ DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
3) Turn ignition switch to ON and Subaru Select Monitor or
OBD-II general scan tool switch to ON.
4) Start engine.
B2M0498
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.
Subaru Select Monitor
Designate mode using function key.
Function mode: F33
F33: Rear oxygen sensor heater current is indicated.
: Is the value more than 0.2 A in function
mode F33?
: Repair connector.
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NOTE:
In this case, repair the following:
Poor contact in rear oxygen sensor connector
Poor contact in rear oxygen sensor connecting harness
connector
Poor contact in ECM connector
: Go to step10S3.
OBD-II scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
B2M0554A
10S3CHECK OUTPUT SIGNAL FROM ECM.
(USING VOLTAGE METER.)
1) Start and idle the engine.
2) Measure voltage between ECM connector and chassis
ground.
: Connector & terminal
(B84) No. 37 (+)—Chassis ground ( ):
Is the voltage less than 1.0 V?
: Go to step10S4.
: Go to next.
: Does the voltage change less than 1.0 V by
shaking harness and connector of ECM
while monitoring the value with voltage
meter?
: Repair poor contact in ECM connector.
: Go to next step 3).
B2M0554A
3) Disconnect connector from rear oxygen sensor.
4) Measure voltage between ECM connector and chassis
ground.
: Connector & terminal
(B84) No. 37 (+)—Chassis ground ( ):
Is the voltage less than 1.0 V?
: Replace ECM.
: Repair battery short circuit in harness between
ECM and rear oxygen sensor connector. After
repair, replace ECM.
OBD0710C
10S4CHECK POWER SUPPLY TO REAR OXY-
GEN SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from rear oxygen sensor.
3) Turn ignition switch to ON.
4) Measure voltage between rear oxygen sensor connec-
tor and engine ground or chassis ground.
: Connector & terminal
2200 cc California spec. vehicles
(B19) No. 2 (+)—Engine ground ( ):
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Except 2200 cc California spec. vehicles
(T6) No. 2 (+)—Chassis ground ( ):
Is the voltage more than 10 V?
: Go to step10S5.
: Repair power supply line.
NOTE:
In this case, repair the following:
Open circuit in harness between main relay and rear
oxygen sensor connector
Poor contact in rear oxygen sensor connector
Poor contact in rear oxygen sensor connecting harness
connector (Except 2200 cc California spec. vehicles)
OBD0706
10S5
CHECK REAR OXYGEN SENSOR.
1) Turn ignition switch to OFF.
2) Measure resistance between rear oxygen sensor con-
nector terminals.
: Terminals
No. 1—No. 2:
Is the resistance less than 30Ω?
: Repair harness and connector.
NOTE:
In this case, repair the following:
Open circuit in harness between rear oxygen sensor and
ECM connector
Poor contact in rear oxygen sensor connector
Poor contact in ECM connector
Poor contact in rear oxygen sensor connecting harness
connector
: Replace rear oxygen sensor.
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B2M0047
(2) Disconnect connector from fuel tank.
(3) Start the engine, and run it until it stalls.
(4) After stopping the engine, crank the engine for 5 to
7 seconds to reduce fuel pressure.
(5) Turn ignition switch to OFF.
B2M0047
2) Connect connector to fuel tank.
OBD0711
3) Disconnect fuel delivery hose from fuel filter, and con-
nect fuel pressure gauge.
G2M0348
4) Start the engine and idle while gear position is neutral.
5) Measure fuel pressure while disconnecting pressure
regulator vacuum hose from intake manifold.
: Is fuel pressure between 226 and 275 kPa
(2.3—2.8 kg/cm2,33—40 psi)?
: Go to next step 6).
: Repair the following items.
Fuel pressure too highClogged fuel return line or bent
hose
Fuel pressure too lowImproper fuel pump discharge
Clogged fuel supply line
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6) After connecting pressure regulator vacuum hose, mea-
sure fuel pressure.
: Is fuel pressure between 157 and 206 kPa
(1.6—2.1 kg/cm2,23—30 psi)?
: Go to step10T4.
: Repair the following items.
Fuel pressure too highFaulty pressure regulator
Clogged fuel return line or bent
hose
Fuel pressure too lowFaulty pressure regulator
Improper fuel pump discharge
Clogged fuel supply line
WARNING:
Before removing fuel pressure gauge, release fuel
pressure.
NOTE:
If fuel pressure does not increase, squeeze fuel return
hose 2 to 3 times, then measure fuel pressure again.
If out of specification as measured at this step, check or
replace pressure regulator and pressure regulator vacuum
hose.
OBD0145A
10T4CHECK ENGINE COOLANT TEMPERA-
TURE SENSOR.
DTC P0117 [T10I0].>
1) Turn ignition switch to OFF.
2) Connect the Subaru Select Monitor or the OBD-II gen-
eral scan tool to data link connector.
3) Start the engine and warm-up completely.
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B2M0479
4) Read data on Subaru Select Monitor or the OBD-II gen-
eral scan tool.
Subaru Select Monitor
Designate mode using function key.
Function mode: F04
F04: Water temperature is indicated in“°C”and“°F”.
: Is temperature greater than 60°Cor140°Fin
function mode F04?
: Go to step10T5.
: Replace engine coolant temperature sensor.
OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
OBD0145A
10T5
CHECK MASS AIR FLOW SENSOR.
1) Turn ignition switch to OFF.
2) Connect the Subaru Select Monitor or the OBD-II gen-
eral scan tool to data link connector.
3) Start the engine and warm-up engine until coolant tem-
perature is greater than 60°C (140°F).
4) Place the selector lever in“N”or“P”position.
5) Turn A/C switch to OFF.
6) Turn all accessory switches to OFF.
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OBD0145A
10V1CONNECT SUBARU SELECT MONITOR
OR THE OBD-II GENERAL SCAN TOOL,
AND READ DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
3) Turn ignition switch to ON and Subaru Select Monitor or
OBD-II general scan tool switch to ON.
4) Start engine.
H2M1308
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.
Subaru Select Monitor
Designate mode using function key.
Function mode: F44
F44: Fuel temperature is indicated in“°C”and“°F”.
: Is the value greater than 150°Cor300°Fin
function mode F44?
: Go to step10V2.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time.
OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
G2M0340
10V2CHECK HARNESS BETWEEN FUEL TEM-
PERATURE SENSOR AND ECM CON-
NECTOR.
1) Turn ignition switch to OFF.
2) Remove access hole lid.
3) Disconnect connector from fuel pump.
OBD0145A
4) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
5) Turn ignition switch and Subaru Select Monitor or
OBD-II general scan tool switch to ON.
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