1996 SUBARU LEGACY air condition

OBD0220
M: DTC P0136
—REAR OXYGEN SENSOR CIRCUIT
MALFUNCTION (RO2
—V)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
10M1Check DTC P0130 on display.
10M2Check failure cause of P0130.
10M3Check rear oxygen sensor data.

10M4Check harness between rear oxygen sensor
and ECM connector.
10M5Check exhaust system.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.




172
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

OBD0229
N: DTC P0139
—REAR OXYGEN SENSOR CIRCUIT SLOW
RESPONSE (RO2
—R)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
10N1Check DTC P0136 on display.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

WIRING DIAGRAM:

LHD Model
B2M0760
177
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

OBD0232
O: DTC P0141
—REAR OXYGEN SENSOR HEATER
CIRCUIT MALFUNCTION (RO2H)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
10O1Check DTC P0135 on display.
10O2Connect Subaru Select Monitor or the OBD-II
general scan tool, and read data.
10O3Check output signal from ECM. (Using voltage
meter.)
10O4Check power supply to rear oxygen sensor.
10O5Check rear oxygen sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.





179
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

OBD0240
P: DTC P0170
—FUEL TRIM MALFUNCTION (FUEL)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Erroneous idling

Engine stalls.

Poor driving performance
10P1Check exhaust system.
10P2Check air intake system.
10P3Check fuel pressure.
10P4Check engine coolant temperature sensor.

10P5Check mass air flow sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODE.





185
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

H2M1306
Q: DTC P0180
—FUEL TEMPERATURE SENSOR A CIRCUIT
MALFUNCTION (TNKT)—
DTC DETECTING CONDITION:

Immediately at fault recognition
10Q1Connect Subaru Select Monitor or the OBD-II
general scan tool, and read data.

10Q2Check harness between fuel temperature
sensor and ECM connector.
10Q3Check harness between fuel temperature
sensor and ECM connector.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

WIRING DIAGRAM:

LHD Model
B2M0916

190
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

H2M1350
R: DTC P0181
—FUEL TEMPERATURE SENSOR A CIRCUIT
RANGE/PERFORMANCE PROBLEM
(TNKT
—F)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
10R1Check DTC P0180 on display.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

WIRING DIAGRAM:

LHD Model
B2M0916
195
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

OBD0283
AA: DTC P0325
—KNOCK SENSOR CIRCUIT MALFUNCTION
(KNOCK)—
DTC DETECTING CONDITION:

Immediately at fault recognition
TROUBLE SYMPTOM:

Poor driving performance

Knocking occurs.
10AA1Check harness between knock sensor and
ECM connector.


10AA2Check knock sensor.
10AA3Check knock sensor.
10AA4Check input signal for ECM.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.


211
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

B2M0244A
10AA3
CHECK KNOCK SENSOR.
1) Disconnect connector from knock sensor.
2) Measure resistance between knock sensor connector
terminal and engine ground.
: Terminal
No. 1—Engine ground:
Is the resistance less than 400 kΩ?
: Replace knock sensor.
: Repair short circuit in harness between knock
sensor connector and ECM connector.
NOTE:
The harness between both connectors is shielded. Repair
short circuit of harness together with shield.
B2M0561A
10AA4
CHECK INPUT SIGNAL FOR ECM.
1) Connect connectors to ECM and knock sensor.
2) Turn ignition switch to ON.
3) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 3 (+)—Chassis ground ():
Is the voltage more than 2 V?
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. (However, the pos-
sibility of poor contact still remains.)
NOTE:
In this case, repair the following:

Poor contact in knock sensor connector

Poor contact in ECM connector

Poor contact in coupling connector (B21)
: Repair poor contact in ECM connector.
214
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code