2004 SUBARU FORESTER sensor

EN(H4DOTC 2.5)-65
ENGINE (DIAGNOSTIC)
List of Diagnostic Trouble Code (DTC)
17.List of Diagnostic Trouble Code (DTC)
A: LIST
DTC Item NOTE
P0031 HO2S Heater Control Circuit Low
(Bank 1 Sensor 1) CUIT LOW (BANK 1 SENSOR 1), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0032 HO2S Heater Control Circuit High
(Bank 1 Sensor 1) CUIT HIGH (BANK 1 SENSOR 1), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0037 HO2S Heater Control Circuit Low
(Bank 1 Sensor 2) CUIT LOW (BANK 1 SENSOR 2), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0038 HO2S Heater Control Circuit High
(Bank 1 Sensor 2) CUIT HIGH (BANK 1 SENSOR 2), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0102 Mass or Volume Air Flow Circuit
Low Input CIRCUIT LOW INPUT, Diagnostic Procedure with Diagnostic Trouble Code
(DTC).>
P0103 Mass or Volume Air Flow Circuit
High Input CIRCUIT HIGH INPUT, Diagnostic Procedure with Diagnostic Trouble Code
(DTC).>
P0107 Manifold Absolute Pressure/Baro-
metric Pressure Circuit Low Input SURE/BAROMETRIC PRESSURE CIRCUIT LOW INPUT, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>
P0108 Manifold Absolute Pressure/Baro-
metric Pressure Circuit High Input SURE/BAROMETRIC PRESSURE CIRCUIT HIGH INPUT, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>
P0112 Intake Air Temperature Circuit Low
Input CIRCUIT LOW INPUT, Diagnostic Procedure with Diagnostic Trouble Code
(DTC).>
P0113 Intake Air Temperature Circuit High
Input CIRCUIT HIGH INPUT, Diagnostic Procedure with Diagnostic Trouble Code
(DTC).>
P0117 Engine Coolant Temperature Cir-
cuit Low Input TURE CIRCUIT LOW INPUT, Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P0118 Engine Coolant Temperature Cir-
cuit High Input TURE CIRCUIT HIGH INPUT, Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P0122 Throttle/Pedal Position Sensor/
Switch “A” Circuit Low Input SENSOR/SWITCH “A” CIRCUIT LOW INPUT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P0123 Throttle/Pedal Position Sensor/
Switch “A” Circuit High Input SENSOR/SWITCH “A” CIRCUIT HIGH INPUT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P0131 O
2 Sensor Circuit Low Voltage
(Bank 1 Sensor 1) VOLTAGE (BANK 1 SENSOR 1), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0132 O
2 Sensor Circuit High Voltage
(Bank 1 Sensor 1) VOLTAGE (BANK 1 SENSOR 1), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0134 O
2 Sensor Circuit No Activity
Detected (Bank 1 Sensor 1) ACTIVITY DETECTED (BANK 1 SENSOR 1), Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>

EN(H4DOTC 2.5)-66
ENGINE (DIAGNOSTIC)
List of Diagnostic Trouble Code (DTC)
P0137 O2 Sensor Circuit Low Voltage
(Bank 1 Sensor 2) VOLTAGE (BANK 1 SENSOR 2), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0138 O
2 Sensor Circuit High Voltage
(Bank 1 Sensor 2) VOLTAGE (BANK 1 SENSOR 2), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0171 System Too Lean (Bank 1) Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P0172 System Too Rich (Bank 1) Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P0222 Throttle/Pedal Position Sensor/
Switch “B” Circuit Low Input SENSOR/SWITCH “B” CIRCUIT LOW INPUT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P0223 Throttle/Pedal Position Sensor/
Switch “B” Circuit High Input SENSOR/SWITCH “B” CIRCUIT HIGH INPUT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P0230 Fuel Pump Primary Circuit CUIT, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P0245 Turbo/Super Charger Wastegate
Solenoid “A” Low WASTEGATE SOLENOID “A” LOW, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0246 Turbo/Super Charger Wastegate
Solenoid “A” High WASTEGATE SOLENOID “A” HIGH, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0327 Knock Sensor 1 Circuit Low Input
(Bank 1 or Single Sensor) LOW INPUT (BANK 1 OR SINGLE SENSOR), Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P0328 Knock Sensor 1 Circuit High Input
(Bank 1 or Single Sensor) HIGH INPUT (BANK 1 OR SINGLE SENSOR), Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P0335 Crankshaft Position Sensor “A” Cir-
cuit SENSOR “A” CIRCUIT, Diagnostic Procedure with Diagnostic Trouble Code
(DTC).>
P0340 Camshaft Position Sensor “A” Cir-
cuit (Bank 1 or Single Sensor) SOR “A” CIRCUIT (BANK 1 OR SINGLE SENSOR), Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>
P0345 Camshaft Position Sensor “A” Cir-
cuit (Bank 2) SOR “A” CIRCUIT (BANK 2), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P0458 Evaporative Emission Control Sys-
tem Purge Control Valve Circuit Low CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT LOW, Diagnostic
Procedure with Diagnostic Trouble Code (DTC).>
P0459 Evaporative Emission Control Sys-
tem Purge Control Valve Circuit High CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT HIGH, Diagnos-
tic Procedure with Diagnostic Trouble Code (DTC).>
P0462 Fuel Level Sensor Circuit Low
Input CUIT LOW INPUT, Diagnostic Procedure with Diagnostic Trouble Code
(DTC).>
P0463 Fuel Level Sensor Circuit High
Input CUIT HIGH INPUT, Diagnostic Procedure with Diagnostic Trouble Code
(DTC).>
P0502 Vehicle Speed Sensor Circuit Low
Input CIRCUIT LOW INPUT, Diagnostic Procedure with Diagnostic Trouble Code
(DTC).>
P0503 Vehicle Speed Sensor Intermittent/
Erratic/High INTERMITTENT/ERRATIC/HIGH, Diagnostic Procedure with Diagnostic Trou-
ble Code (DTC).> DTC Item NOTE

EN(H4DOTC 2.5)-67
ENGINE (DIAGNOSTIC)
List of Diagnostic Trouble Code (DTC)
P0512 Starter Request Circuit Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P0513 Incorrect Immobilizer Key Procedure with Diagnostic Trouble Code (DTC).>
P0519 Idle Control System Malfunction
(Fail-Safe) MALFUNCTION (FAIL-SAFE), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P0545 Exhaust Gas Temperature Sensor
Circuit Low-Bank 1 TURE SENSOR CIRCUIT LOW - BANK 1, Diagnostic Procedure with Diag-
nostic Trouble Code (DTC).>
P0546 Exhaust Gas Temperature Sensor
Circuit High-Bank 1 TURE SENSOR HIGH - BANK 1, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P0600 Serial Communication Link LINK, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P0604 Internal Control Module Random
Access Memory (RAM) Error ULE READ ACCESS MEMORY (RAM) ERROR, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P0605 Internal Control Module Read
Access Memory (RAM) Error ULE READ ONLY MEMORY (ROM) ERROR, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P0607 Control Module Performance MANCE, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P0638 Throttle Actuator Control Range/
Performance (Bank 1) TROL RANGE/PERFORMANCE (BANK 1), Diagnostic Procedure with Diag-
nostic Trouble Code (DTC).>
P0691 Cooling Fan 1 Control Circuit Low CIRCUIT LOW, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P0692 Cooling Fan 1 Control Circuit High CIRCUIT HIGH, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P0700 Transmission Control System (MIL
Request) SYSTEM (MIL REQUEST), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P0851 Neutral Switch Input Circuit Low CIRCUIT LOW (MT MODEL), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P0852 Neutral Switch Input Circuit High CIRCUIT HIGH (AT MODEL), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P1086 Tumble Generated Valve Position
Sensor 2 Circuit Low POSITION SENSOR 2 CIRCUIT LOW, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
P1087 Tumble Generated Valve Position
Sensor 2 Circuit High POSITION SENSOR 2 CIRCUIT HIGH, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
P1088 Tumble Generated Valve Position
Sensor 1 Circuit Low POSITION SENSOR 1 CIRCUIT LOW, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
P1089 Tumble Generated Valve Position
Sensor 1 Circuit High POSITION SENSOR 1 CIRCUIT HIGH, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
P1090 Tumble Generated Valve System 1
(Valve Open) SYSTEM 1 (VALVE OPEN), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P1091 Tumble Generated Valve System 1
(Valve Close) SYSTEM 1 (VALVE CLOSE), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).> DTC Item NOTE

EN(H4DOTC 2.5)-68
ENGINE (DIAGNOSTIC)
List of Diagnostic Trouble Code (DTC)
P1092 Tumble Generated Valve System 2
(Valve Open) SYSTEM 2 (VALVE OPEN), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P1093 Tumble Generated Valve System 2
(Valve Close) SYSTEM 2 (VALVE CLOSE), Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
P1094 Tumble Generated Valve Signal 1
Circuit Malfunction (Open) SIGNAL 1 CIRCUIT MALFUNCTION (OPEN), Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P1095 Tumble Generated Valve Signal 1
Circuit Malfunction (Short) SIGNAL 1 CIRCUIT MALFUNCTION (SHORT), Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P1096 Tumble Generated Valve Signal 2
Circuit Malfunction (Open) SIGNAL 2 CIRCUIT MALFUNCTION (OPEN), Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P1097 Tumble Generated Valve Signal 2
Circuit Malfunction (Short) SIGNAL 2 CIRCUIT MALFUNCTION (SHORT), Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P1110 Atmospheric Pressure Sensor Cir-
cuit Malfunction (Low Input) SENSOR CIRCUIT MALFUNCTION (LOW INPUT), Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>
P1111 Atmospheric Pressure Sensor Cir-
cuit Malfunction (High Input) SENSOR CIRCUIT MALFUNCTION (HIGH INPUT), Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>
P1160 Return Spring Failure Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P1518 Starter Switch Circuit Low Input LOW INPUT, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P1544 Exhaust Gas Temperature Too High TURE TOO HIGH, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P1560 Back-Up Voltage Circuit Malfunction MALFUNCTION, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
P1570 ANTENNA nostic Trouble Code (DTC).>
P1571 Reference Code Incompatibility nostics Procedure with Diagnostic Trouble Code (DTC).>
P1572 IMM Circuit Failure (Except
Antenna Circuit) CIRCUIT), Diagnostics Procedure with Diagnostic Trouble Code (DTC).>
P1574 Key Communication Failure Procedure with Diagnostic Trouble Code (DTC).>
P1576 EGI Control Module EEPROM tics Procedure with Diagnostic Trouble Code (DTC).>
P1577 IMM Control Module EEPROM tics Procedure with Diagnostic Trouble Code (DTC).>
P2088 OCV Solenoid Valve Signal A Cir-
cuit Open (Bank 1) NAL A CIRCUIT OPEN (BANK 1), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P2089 OCV Solenoid Valve Signal A Cir-
cuit Short (Bank 1) NAL A CIRCUIT SHORT (BANK 1), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P2092 OCV Solenoid Valve Signal A Cir-
cuit Open (Bank 2) NAL A CIRCUIT OPEN (BANK 2), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
P2093 OCV Solenoid Valve Signal A Cir-
cuit Short (Bank 2) NAL A CIRCUIT SHORT (BANK 2), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).> DTC Item NOTE

EN(H4DOTC 2.5)-69
ENGINE (DIAGNOSTIC)
List of Diagnostic Trouble Code (DTC)
P2101 Throttle Actuator Control Motor Cir-
cuit Range/Performance TROL MOTOR CIRCUIT RANGE/PERFORMANCE, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>
P2102 Throttle Actuator Control Motor Cir-
cuit Low TROL MOTOR CIRCUIT LOW, Diagnostic Procedure with Diagnostic Trou-
ble Code (DTC).>
P2103 Throttle Actuator Control Motor Cir-
cuit High TROL MOTOR CIRCUIT HIGH, Diagnostic Procedure with Diagnostic Trou-
ble Code (DTC).>
P2109 Throttle/Pedal Position Sensor A
Minimum Stop Performance SENSOR A MINIMUM STOP PERFORMANCE, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P2122 Throttle/Pedal Position Sensor/
Switch “D” Circuit Low Input SENSOR/SWITCH “D” CIRCUIT LOW INPUT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P2123 Throttle/Pedal Position Sensor/
Switch “D” Circuit High Input SENSOR/SWITCH “D” CIRCUIT HIGH INPUT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P2127 Throttle/Pedal Position Sensor/
Switch “E” Circuit Low Input SENSOR/SWITCH “E” CIRCUIT LOW INPUT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P2128 Throttle/Pedal Position Sensor/
Switch “E” Circuit High Input SENSOR/SWITCH “E” CIRCUIT HIGH INPUT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
P2135 Throttle/Pedal Position Sensor/
Switch “A”/“B” Voltage Rationality SENSOR/SWITCH “A”/“B” VOLTAGE RATIONALITY, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>
P2138 Throttle/Pedal Position Sensor/
Switch “D”/“E” Voltage Rationality SENSOR/SWITCH “D”/“E” VOLTAGE RATIONALITY, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).> DTC Item NOTE

EN(H4DOTC 2.5)-70
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
18.Diagnostic Procedure with Diagnostic Trouble Code (DTC)
A: DTC P0031 HO2S HEATER CONTROL CIRCUIT LOW (BANK 1 SENSOR 1)
DTC DETECTING CONDITION:
Immediately at fault recognition.
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02359
SBF-5
B47 1 2 3 5 4 6
E
E
B21
E236
72
3
26
33
25
ECM
B134
1
3 2
4
B262
34 12
56
123
4
56
78
9
1011 12
1314 15 16
B21 B47 B262
B134
56 7
82 1
94 310
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31
MAIN RELAY1234BATTERY
FRONT OXYGEN
(A/F) SENSOR

EN(H4DOTC 2.5)-71
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 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
(B262) No. 1 (+) — Engine ground (
−):Is the voltage more than 10 V? Go to step 2.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
2 CHECK GROUND CIRCUIT FOR ECM.
Measure the resistance of harness between
ECM connector and chassis ground.
Connector & terminal
(B134) No. 6 — Chassis ground:
(B134) No. 7 — Chassis ground:Is the resistance less than 5
Ω?Go to step 3.Repair the harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
ECM and engine
ground cable
 Poor contact in
ECM connector.
 Poor contact in
coupling connector
3 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
“READ CURRENT DATA SHOWN ON DIS-
PLAY FOR ENGINE”. 2.5)-27, Subaru Select Monitor.>
 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 4.
4 CHECK OUTPUT SIGNAL FROM ECM.
1) Start and idle the engine.
2) Measure the voltage between ECM con-
nector and chassis ground.
Connector & terminal
(B134) No. 2 (+) — Chassis ground (
−):
(B134) No. 3 (+) — Chassis ground (
−):Is the voltage less than 1 V? Go to step 6.Go to step 5.
5 CHECK OUTPUT SIGNAL FROM ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B134) No. 2 (+) — Chassis ground (
−):
(B134) No. 3 (+) — Chassis ground (
−):Does the voltage change by
shaking the harness and con-
nector of ECM while monitor-
ing the value with voltage
meter?Repair the poor
contact in ECM
connector.Go to step 6.

EN(H4DOTC 2.5)-72
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
6 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. 1 — No. 2:Is the resistance less than 10
Ω?Repair the harness
and connector.
N
OTE:
In this case repair
the following:
 Open or ground
short circuit in har-
ness between front
oxygen (A/F) sen-
sor and ECM con-
nector
 Poor contact in
front oxygen (A/F)
sensor connector
 Poor contact in
ECM connector.Replace the front
oxygen (A/F) sen-
sor. FU(H4DOTC 2.5)-
36, Front Oxygen
(A/F) Sensor.> Step Check Yes No