2009 SUBARU TRIBECA ac 25 procedure

EN(H6DO)(diag)-176
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
AO:DTC P0137 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 2)
DTC DETECTING CONDITION:
•Detected when two consecutive driving cycles with fault occur.
•GENERAL DESCRIPTION (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>
CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.

EN(H6DO)(diag)-177
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
WIRING DIAGRAM:
EN-03738
SBF-5
B47
12
35
46
A3D7D1D2A5D3
2
373635363452B21
E2
ECM
C5B15B4C4B30
431
REAROXYGENSENSOR LH
E25
2
431
REAROXYGENSENSOR RH
E61
E3B22
14
1315E3
B221011129
B424
B47
3456
12
B21
123412131415567816171819910 1120212223 24 25 2627 28 29 3031 32 33
3534 37363938 41404342 4445 47464948 51505352 54
B135
567821943102422 23 2511 12 13 14 1526 2728
16 17 18 1920 2129 30 31 32 33 34 35
B:B134
56 7821943102422 23 2511 12 13 14 1526 2728
16 1718 19 20 2133 34293230 31
A:
16
B134A:
B135B:
B136C:
B137D:
B22
1234567891011 121314 15 16
B136
567821943102422 23 2511 12 13141526 2728
1617 18 19 20 2133 3429323031 35
C:B137
5678219431022 2311 12 13 14 1524 2526
16 1718 19 20 2127 28 29 30 31
D:
12345678
B424
B122
3412
E25E61
MAIN RELAYBATTERY
EE
* : TERMINAL NO. OPTIONAL ARRANGEMENT
***B1
**
B122

EN(H6DO)(diag)-178
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK ANY OTHER DTC ON DISPLAY.Is any other DTC displayed? Check DTC using
“List of Diagnostic
Tr o u b l e C o d e
(DTC)”. EN(H6DO)(diag)-
69, List of Diag-
nostic Trouble
Code (DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0137.
Go to step 2.
2CHECK REAR OXYGEN SENSOR DATA.
1) Warm-up the engine until engine coolant
temperature is above 70°C (158°F), and keep
the engine speed at 5,000 rpm.
2) Read the data of rear oxygen sensor signal
using Subaru Select Monitor or general scan
tool.
NOTE:•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”. to EN(H6DO)(diag)-26, Subaru Select Moni-
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the voltage more than 490
mV?
Go to step 5.Go to step 3.
3CHECK HARNESS BETWEEN ECM AND
REAR OXYGEN SENSOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and
rear oxygen sensor.
3) Measure the resistance of harness
between ECM and rear oxygen sensor con-
nector.
Connector & terminal
(B135) No. 4 — (E61) No. 3:
(B135) No. 30 — (E61) No. 4:
Is the resistance more than
3Ω?
Repair the open
circuit of harness
between ECM and
rear oxygen sen-
sor connector.
Go to step 4.
4CHECK HARNESS BETWEEN REAR OXY-
GEN SENSOR AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from rear oxygen
sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between rear oxygen
sensor harness connector and chassis ground.
Connector & terminal
(E61) No. 3 (+) — Chassis ground (–):
Is the voltage 0.2 — 0.5 V? Replace the rear
oxygen sensor.
FU(H6DO)-30,
Rear Oxygen Sen-
sor.>
Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following item:
•Open circuit
of harness be-
tween rear oxy-
gen sensor and
ECM connector
•Poor contact
in rear oxygen
sensor connec-
tor
•Poor contact
in ECM connec-
tor

EN(H6DO)(diag)-179
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
5 CHECK EXHAUST SYSTEM.
Check exhaust system parts.
NOTE:
Check the following item.
•Loose part and incomplete installation of ex-
haust system
•Damage (crack, hole etc.) of parts
•Looseness and ill fitting of parts between
front oxygen (A/F) sensor and rear oxygen sen-
sor
Is there any fault in exhaust
system?
Repair or replace
faulty par ts.
Replace the rear
oxygen sensor.
FU(H6DO)-30,
Rear Oxygen Sen-
sor.>
Step Check Yes No

EN(H6DO)(diag)-180
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
AP:DTC P0138 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 2)
DTC DETECTING CONDITION:
•Detected when two consecutive driving cycles with fault occur.
•GENERAL DESCRIPTION (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>
CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.

EN(H6DO)(diag)-181
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
WIRING DIAGRAM:
EN-03738
SBF-5
B47
12
35
46
A3D7D1D2A5D3
2
373635363452B21
E2
ECM
C5B15B4C4B30
431
REAROXYGENSENSOR LH
E25
2
431
REAROXYGENSENSOR RH
E61
E3B22
14
1315E3
B221011129
B424
B47
3456
12
B21
123412131415567816171819910 1120212223 24 25 2627 28 29 3031 32 33
3534 37363938 41404342 4445 47464948 51505352 54
B135
567821943102422 23 2511 12 13 14 1526 2728
16 17 18 1920 2129 30 31 32 33 34 35
B:B134
56 7821943102422 23 2511 12 13 14 1526 2728
16 1718 19 20 2133 34293230 31
A:
16
B134A:
B135B:
B136C:
B137D:
B22
1234567891011 121314 15 16
B136
567821943102422 23 2511 12 13141526 2728
1617 18 19 20 2133 3429323031 35
C:B137
5678219431022 2311 12 13 14 1524 2526
16 1718 19 20 2127 28 29 30 31
D:
12345678
B424
B122
3412
E25E61
MAIN RELAYBATTERY
EE
* : TERMINAL NO. OPTIONAL ARRANGEMENT
***B1
**
B122

EN(H6DO)(diag)-182
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK ANY OTHER DTC ON DISPLAY.Is any other DTC displayed? Check DTC using
“List of Diagnostic
Tr o u b l e C o d e
(DTC)”. EN(H6DO)(diag)-
69, List of Diag-
nostic Trouble
Code (DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0138.
Go to step 2.
2CHECK REAR OXYGEN SENSOR DATA.
1) Warm-up the engine until engine coolant
temperature is above 70°C (158°F), and rap-
idly reduce the engine speed from 5,000 rpm.
2) Read the data of rear oxygen sensor signal
using Subaru Select Monitor or general scan
tool.
NOTE:•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”. to EN(H6DO)(diag)-26, Subaru Select Moni-
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the voltage 250 mV or less? Go to step 5.Go to step 3.
3CHECK HARNESS BETWEEN ECM AND
REAR OXYGEN SENSOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and
rear oxygen sensor.
3) Measure the resistance of harness
between ECM and rear oxygen sensor con-
nector.
Connector & terminal
(B135) No. 4 — (E61) No. 3:
(B135) No. 30 — (E61) No. 4:
Is the resistance more than
3Ω?
Repair the open
circuit of harness
between ECM and
rear oxygen sen-
sor connector.
Go to step 4.
4CHECK HARNESS BETWEEN REAR OXY-
GEN SENSOR AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from rear oxygen
sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between rear oxygen
sensor harness connector and chassis ground.
Connector & terminal
(E61) No. 3 (+) — Chassis ground (–):
Is the voltage 0.2 — 0.5 V? Replace the rear
oxygen sensor.
FU(H6DO)-30,
Rear Oxygen Sen-
sor.>
Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following item:
•Open circuit
of harness be-
tween rear oxy-
gen sensor and
ECM connector
•Poor contact
in rear oxygen
sensor connec-
tor
•Poor contact
in ECM connec-
tor

EN(H6DO)(diag)-183
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
5 CHECK EXHAUST SYSTEM.
Check exhaust system parts.
NOTE:
Check the following item.
•Loose part and incomplete installation of ex-
haust system
•Damage (crack, hole etc.) of parts
•Looseness and ill fitting of parts between
front oxygen (A/F) sensor and rear oxygen sen-
sor
Is there any fault in exhaust
system?
Repair or replace
faulty par ts.
Replace the rear
oxygen sensor.
FU(H6DO)-30,
Rear Oxygen Sen-
sor.>
Step Check Yes No