check engine SUBARU FORESTER 2004 Service Repair Manual
[x] Cancel search | Manufacturer: SUBARU, Model Year: 2004, Model line: FORESTER, Model: SUBARU FORESTER 2004Pages: 2870, PDF Size: 38.67 MB
Page 1163 of 2870
EN(H4SO)-65
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
Step Check Yes No
1 CHECK IGNITION SYSTEM FOR SPARKS.
1) Remove the plug cord cap from each spark
plug.
2) Install the new spark plug on plug cord cap.
CAUTION:
Do not remove the spark plug from engine.
3) Contact the spark plug’s thread portion on
engine.
4) While opening the throttle valve fully, crank
the engine to check that spark occurs at each
cylinder.Does spark occur at each cyl-
inder?Check fuel pump
system.
FUEL PUMP CIR-
CUIT, Diagnostics
for Engine Start-
ing Failure.>Go to step 2.
2 CHECK POWER SUPPLY CIRCUIT FOR IG-
NITION COIL & IGNITOR ASSY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ignition coil
& ignitor ASSY.
3) Turn the ignition switch to ON.
4) Measure the power supply voltage between
ignition coil & ignitor ASSY connector and
engine ground.
Connector & terminal
(E12) No. 2 (+) — Engine ground (
−):Is the voltage more than 10 V? Go to step 3.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
ignition coil & igni-
tor ASSY, and
main relay connec-
tor
Poor contact in
coupling connector
Blown out fuse
3 CHECK HARNESS OF IGNITION COIL & IG-
NITOR ASSY GROUND CIRCUIT.
1) Turn the ignition switch to OFF.
2) Measure the resistance between ignition
coil & ignitor ASSY connector and engine
ground.
Connector & terminal
(E12) No. 3 — Engine ground:Is the resistance less than 5
Ω?Go to step 4.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
ignition coil & igni-
tor ASSY connec-
tor and engine
ground terminal
4 CHECK IGNITION COIL & IGNITOR ASSY.
1) Remove the spark plug cords.
2) Measure the resistance between spark
plug cord contact portions to check secondary
coil.
Te r m i n a l s
No. 1 — No. 2:
No. 3 — No. 4:Is the resistance 10 — 15 kΩ? Go to step 5.Replace the igni-
tion coil & ignitor
ASSY.
tion Coil & Ignitor
Assembly.>
5 CHECK INPUT SIGNAL FOR IGNITION COIL
& IGNITOR ASSY.
1) Connect the connector to ignition coil &
ignitor ASSY.
2) Check if voltage varies synchronously with
engine speed when cranking, while monitoring
voltage between ignition coil & ignitor ASSY
connector and engine ground.
Connector & terminal
(E12) No. 1 (+) — Engine ground (
−):
(E12) No. 4 (+) — Engine ground (
−):Does the voltage vary more
than 10 V?Go to step 6.Replace the igni-
tion coil & ignitor
ASSY.
tion Coil & Ignitor
Assembly.>
Page 1164 of 2870
EN(H4SO)-66
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
6 CHECK HARNESS BETWEEN ECM AND IG-
NITION COIL & IGNITOR ASSY CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Disconnect the connector from ignition coil
& ignitor ASSY.
4) Measure the resistance of harness
between ECM and ignition coil & ignitor ASSY
connector.
Connector & terminal
(B134) No. 32 — (E12) No. 1:
(B134) No. 32 — (E12) No. 4:Is the resistance less than 1
Ω?Go to step 7.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
ECM and ignition
coil & ignitor ASSY
connector.
Poor contact in
coupling connector
7 CHECK HARNESS BETWEEN ECM AND IG-
NITION COIL & IGNITOR ASSY CONNEC-
TOR.
Measure the resistance of harness between
ECM and engine ground.
Connector & terminal:
(B134) No. 32 — Engine ground:Is the resistance more than 1
MΩ?Go to step 8.Repair ground
short circuit in har-
ness between
ECM and ignition
coil & ignitor ASSY
connector.
8 CHECK POOR CONTACT.
Check poor contact in ECM connector. Is there poor contact in ECM
connector?Repair the poor
contact in ECM
connector.Check fuel pump
circuit.
FUEL PUMP CIR-
CUIT, Diagnostics
for Engine Start-
ing Failure.> Step Check Yes No
Page 1166 of 2870
EN(H4SO)-68
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
Step Check Yes No
1 CHECK OPERATING SOUND OF FUEL
PUMP.
Check that the fuel pump is in operation for two
seconds when turning the ignition switch to
ON.
N
OTE:
Fuel pump operation can also be executed us-
ing Subaru Select Monitor.
Refer to “Compulsory Valve Operation Check
Mode” for procedures.
operating sound?Check the fuel
injector circuit.
FUEL INJECTOR
CIRCUIT, Diag-
nostics for Engine
Starting Failure.>Go to step 2.
2 CHECK GROUND CIRCUIT OF FUEL PUMP.
1) Turn the ignition switch to OFF.
2) Remove the fuel pump access hole lid.
3) Disconnect the connector from fuel pump.
4) Measure the resistance of harness connec-
tor between fuel pump and chassis ground.
Connector & terminal
(R58) No. 4 — Chassis ground:Is the resistance less than 5
Ω?Go to step 3.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
fuel pump connec-
tor and chassis
grounding terminal
Poor contact in
coupling connector
3 CHECK POWER SUPPLY TO FUEL PUMP.
1) Turn the ignition switch to ON.
2) Measure the voltage of power supply circuit
between fuel pump connector and chassis
ground.
Connector & terminal
(R58) No. 1 (+) — Chassis ground (
−):Is the voltage more than 10 V? Replace the fuel
pump.
Fuel Pump.>Go to step 4.
4 CHECK HARNESS BETWEEN FUEL PUMP
AND FUEL PUMP RELAY CONNECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance of harness connec-
tor between fuel pump and fuel pump relay.
Connector & terminal
(R58) No. 1 — (B46) No. 4:Is the resistance less than 1
Ω?Go to step 5.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
fuel pump connec-
tor and chassis
grounding terminal
Poor contact in
coupling connector
5 CHECK HARNESS BETWEEN FUEL PUMP
AND FUEL PUMP RELAY CONNECTOR.
Measure the resistance of harness between
fuel pump and fuel pump relay connector.
Connector & terminal
(R58) No. 1 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 6.Repair short circuit
in harness
between fuel pump
and fuel pump
relay connector.
6 CHECK FUEL PUMP RELAY.
1) Disconnect the connectors from fuel pump
relay and main relay.
2) Remove the fuel pump relay and main relay
with bracket.
3) Connect the battery to fuel pump relay con-
nector terminals No. 1 and No. 3.
4) Measure the resistance between connector
terminals of fuel pump relay.
Te r m i n a l s
No. 2 — No. 4:Is the resistance less than 10
Ω?Go to step 7.Replace the fuel
pump relay.
Fuel Pump.>
Page 1167 of 2870
EN(H4SO)-69
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
7 CHECK HARNESS BETWEEN ECM AND
FUEL PUMP RELAY CONNECTOR.
1) Disconnect the connector from ECM.
2) Measure the resistance of harness
between ECM and fuel pump relay connector.
Connector & terminal
(B134) No. 26 — (B46) No. 3:Is the resistance less than 1
Ω?Go to step 8.Repair open circuit
in harness
between ECM and
fuel pump relay
connector.
8 CHECK POOR CONTACT.
Check poor contact in ECM connector.Is there poor contact in ECM
connector?Repair the poor
contact in ECM
connector.Check the fuel
injector circuit.
FUEL INJECTOR
CIRCUIT, Diag-
nostics for Engine
Starting Failure.> Step Check Yes No
Page 1168 of 2870
EN(H4SO)-70
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
F: FUEL INJECTOR CIRCUIT
CAUTION:
Check or repair only faulty parts.
After repair or replacement of faulty parts, conduct Clear Memory Mode
WIRING DIAGRAM:
EN-02383
B21
12345678910111213141516
E6E17
E5E16
12
12121212
2223348
91101112
ECM
B134
E5E16E6E17
B21
E2
FUEL INJECTOR
No. 1FUEL INJECTOR
No. 2FUEL INJECTOR
No. 3FUEL INJECTOR
No. 4
BATTERY
F44B61
SBF-5
B47 MAIN RELAY
12
35
46
B47
34
12
56
F44
12345678
B134
1234567891011121314151617181920212223242526272829303132333435
LHDLHD
RHDRHD
7
Page 1169 of 2870
EN(H4SO)-71
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
Step Check Yes No
1 CHECK OPERATION OF EACH FUEL INJEC-
TOR.
While cranking the engine, check that each
fuel injector emits operating sound. Use a
sound scope or apply a screwdriver to the
injector for this check.Does the fuel pump emit oper-
ating sound?Check the fuel
pressure.
INSPECTION,
Fuel Pressure.>Go to step 2.
2 CHECK POWER SUPPLY TO EACH FUEL
INJECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from fuel injector.
3) Turn the ignition switch to ON.
4) Measure the power supply voltage between
fuel injector terminal and engine ground.
Connector & terminal
#1 (E5) No. 2 (+) — Engine ground (
−):
#2 (E16) No. 2 (+) — Engine ground (
−):
#3 (E6) No. 2 (+) — Engine ground (
−):
#4 (E17) No. 2 (+) — Engine ground (
−):Is the voltage more than 10 V? Go to step 3.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
main relay and fuel
injector connector
Poor contact in
main relay connec-
tor
Poor contact in
coupling connector
Poor contact in
fuel injector con-
nector
3 CHECK HARNESS BETWEEN ECM AND
FUEL INJECTOR CONNECTOR.
1) Disconnect the connector from ECM.
2) Measure the resistance of harness
between ECM and fuel injector connector.
Connector & terminal
#1 (B134) No. 34 — (E5) No. 1:
#2 (B134) No. 23 — (E16) No. 1:
#3 (B134) No. 22 — (E6) No. 1:
#4 (B134) No. 8 — (E17) No. 1:Is the resistance less than 1
Ω?Go to step 4.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
ECM and fuel
injector connector
Poor contact in
coupling connector
4 CHECK HARNESS BETWEEN ECM AND
FUEL INJECTOR CONNECTOR.
Measure the resistance of harness between
ECM and fuel injector connector.
Connector & terminal
#1 (B134) No. 34 — Chassis ground:
#2 (B134) No. 23 — Chassis ground:
#3 (B134) No. 22 — Chassis ground:
#4 (B134) No. 8 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 5.Repair ground
short circuit in har-
ness between
ECM and fuel
injector connector.
5 CHECK EACH FUEL INJECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance between each fuel
injector terminals.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 5 — 20 Ω? Go to step 6.Replace the faulty
fuel injector.
6 CHECK POOR CONTACT.
Check poor contact in ECM connector.Is there poor contact in ECM
connector?Repair the poor
contact in ECM
connector.Inspection using
“General Diagnos-
tic Table”
INSPECTION,
General Diagnos-
tic Table.>
Page 1172 of 2870
EN(H4SO)-74
ENGINE (DIAGNOSTIC)
List of Diagnostic Trouble Code (DTC)
P0420 Catalyst System Efficiency Below
Threshold (Bank 1)
Trouble Code (DTC).>
P0458 Evaporative Emission Control Sys-
tem Purge Control Valve Circuit Low
cedure with Diagnostic Trouble Code (DTC).>
P0459 Evaporative Emission Control Sys-
tem Purge Control Valve Circuit High
Procedure with Diagnostic Trouble Code (DTC).>
P0461 Fuel Level Sensor Circuit Range/Per-
formance
Code (DTC).>
P0462 Fuel Level Sensor Circuit Low Input
P0463 Fuel Level Sensor Circuit High Input
P0464 Fuel Level Sensor Circuit Intermittent
(DTC).>
P0483 Cooling Fan Rationality Check
P0502 Vehicle Speed Sensor Circuit Low
Input
P0503 Vehicle Speed Sensor Intermittent/
Erratic/High
P0506 Idle Control System RPM Lower
Than Expected
Code (DTC).>
P0507 Idle Control System RPM Higher
Than Expected
Code (DTC).>
P0512 Starter Request Circuit
P0513 Incorrect Immobilizer Key
P0519 Idle Control System Malfunction
(Fail-Safe)
(DTC).>
P0565 Cruise Control On Signal
P0604 Internal Control Module Random
Access Memory (RAM) Error
nostic Trouble Code (DTC).>
P0691 Cooling Fan 1 Control Circuit Low
P0692 Cooling Fan 1 Control Circuit High
P0703 Torque Converter/Brake Switch “B”
Circuit
(DTC).>
P0705 Transmission Range Sensor Circuit
(PRNDL Input)
P0710 Transmission Fluid Temperature
Sensor Circuit
P0716 Torque converter turbine speed sen-
sor
Page 1177 of 2870
EN(H4SO)-79
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND
FRONT OXYGEN (A/F) SENSOR CONNEC-
TOR.
1) Start the engine, and warm-up the engine.
2) Turn the ignition switch to OFF.
3) Disconnect the connector from ECM and
front oxygen (A/F) sensor.
4) Measure the resistance of harness
between ECM and front oxygen (A/F) sensor
connector.
Connector & terminal
(B136) No. 6 — (B18) No. 3:
(B136) No. 17 — (B18) No. 3:Is the resistance less than 1
Ω?Go to step 2.Repair open circuit
in harness
between ECM and
front oxygen (A/F)
sensor connector.
2 CHECK HARNESS BETWEEN ECM AND
FRONT OXYGEN (A/F) SENSOR CONNEC-
TOR.
Measure the resistance of harness between
ECM and front oxygen (A/F) sensor connector.
Connector & terminal
(B136) No. 13 — (B18) No. 1:
(B136) No. 22 — (B18) No. 2:Is the resistance less than 1
Ω?Go to step 3.Repair open circuit
in harness
between ECM and
front oxygen (A/F)
sensor connector.
3 CHECK HARNESS BETWEEN MAIN RELAY
AND FRONT OXYGEN (A/F) SENSOR CON-
NECTOR.
Measure the resistance of harness between
main relay and front oxygen (A/F) sensor con-
nector.
Connector & terminal
(B47) No. 4 — (B18) No. 4:Is the resistance less than 1
Ω?Go to step 4.Repair open circuit
in harness
between ECM and
front oxygen (A/F)
sensor connector.
4 CHECK FRONT OXYGEN (A/F) SENSOR.
Measure the resistance between front oxygen
(A/F) sensor connector terminals.
Te r m i n a l s
No. 3 — No. 4:Is the resistance less than 5
Ω?Go to step 5.Replace the front
oxygen (A/F) sen-
sor.
Front Oxygen (A/
F) Sensor.>
5 CHECK POOR CONTACT.
Check poor contact in ECM and front oxygen
(A/F) sensor connector. Is there poor contact in ECM or
front oxygen (A/F) sensor con-
nector?Repair poor con-
tact in ECM or
front oxygen (A/F)
sensor connector.Replace the front
oxygen (A/F) sen-
sor.
Front Oxygen (A/
F) Sensor.>
Page 1179 of 2870
EN(H4SO)-81
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK ANY OTHER DTC ON DISPLAY.Does the Subaru Select Moni-
tor or OBD-II general scan tool
indicate DTC P0031 and
P0037 at the same time?Go to step 2.Go to step 5.
2 CHECK POWER SUPPLY TO FRONT OXY-
GEN (A/F) SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from front oxygen
(A/F) sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between front oxygen
(A/F) sensor connector and engine ground.
Connector & terminal
(B18) No. 4 (+) — Engine ground (
−):Is the voltage more than 10 V? Go to step 3.Repair the power
supply line.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
main relay and
front oxygen (A/F)
sensor connector
Poor contact in
front oxygen (A/F)
sensor connector
Poor contact in
main relay connec-
tor
3 CHECK GROUND CIRCUIT FOR ECM.
Measure the resistance of harness between
ECM connector and chassis ground.
Connector & terminal
(B136) No. 5 — Chassis ground:
(B136) No. 16 — Chassis ground:Is the resistance less than 5
Ω?Go to step 4.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
ECM and engine
ground terminal
Poor contact in
ECM connector.
Poor contact in
coupling connector
4 CHECK CURRENT DATA.
1) Start the engine.
2) Read the data of front oxygen (A/F) sensor
heater current using Subaru Select Monitor or
OBD-II general scan tool.
N
OTE:
Subaru Select Monitor
For detailed operation procedure, refer to the
“READ CURRENT DATA FOR ENGINE”.
OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-II General Scan Tool Operation Manual.Is the current more than 0.2 A? Repair poor con-
tact connector.
N
OTE:
In this case repair
the following:
Poor contact in
front oxygen (A/F)
sensor connector
Poor contact in
ECM connector.Go to step 5.
5 CHECK INPUT SIGNAL FROM ECM.
1) Start and idle the engine.
2) Measure the voltage between ECM con-
nector and chassis ground.
Connector & terminal
(B136) No. 6 (+) — Chassis ground (
−):
(B136) No. 17 (+) — Chassis ground (
−):Is the voltage less than 1 V? Go to step 7.Go to step 6.
6 CHECK OUTPUT SIGNAL FROM ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B136) No. 6 (+) — Chassis ground (
−):
(B136) No. 17 (+) — Chassis ground (
−):Is the voltage less than 1 V by
shaking the ECM harness and
connector while monitoring the
value of voltage meter?Repair the poor
contact in ECM
connector.Go to step 7.
Page 1180 of 2870
EN(H4SO)-82
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
7 CHECK FRONT OXYGEN (A/F) SENSOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance between front oxy-
gen (A/F) sensor connector terminals.
Te r m i n a l s
No. 3 — No. 4:Is the resistance less than 10
Ω?Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open or ground
short circuit in har-
ness between front
oxygen (A/F)
sensor and ECM
connector
Poor contact in
front oxygen (A/F)
sensor connector
Poor contact in
ECM connector.Replace the front
oxygen (A/F) sen-
sor.
Fuel.> Step Check Yes No