check engine light 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 2635 of 2870
4AT(H4DOTC)-59
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
H: DTC P0725 ENGINE SPEED INPUT CIRCUIT
DTC DETECTING CONDITION:
Engine speed input signal circuit is open or shorted.
TROUBLE SYMPTOM:
No lock-up (after engine warm-up).
POWER indicator light remains on when vehicle speed is “0”.
WIRING DIAGRAM:
Step Check Yes No
1 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ECM.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM and
ECM.
3) Measure the resistance of harness
between TCM and ECM connector.
Connector & terminal
(B55) No. 13 — (B134) No. 23:Is the resistance less than 1
Ω?Go to step 2.Repair the open
circuit in harness
between TCM and
ECM connector.
AT-01846
B55
23
13
B134
ECM
B55
TCM
B134
12
7
8956 3410 11 12
19 20 2113 14 15 16
17 1822
23
24
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
Page 2636 of 2870
4AT(H4DOTC)-60
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ECM.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B55) No. 13 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 3.Repair the short
circuit in harness
between TCM and
ECM connector.
3 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 5.Go to step 4.
4 CHECK INPUT SIGNAL FOR TCM.
1) Connect the connectors to TCM and ECM.
2) Turn the ignition switch to ON (engine OFF).
3) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B55) No. 13 (+) — Chassis ground (
−):Is the voltage less than 1 V? Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor of TCM and
ECM.Go to step 6.
5 CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
1) Connect the connectors to TCM and ECM.
2) Connect the Subaru Select Monitor to data
link connector.
3) Start the engine and turn Subaru Select
Monitor switch to ON.
4) Idle the engine.
5) Read the data of engine speed using Sub-
aru Select Monitor.
Display shows the engine speed signal value
sent from ECM.Is the revolution value same as
tachometer reading shown on
combination meter?Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor of TCM and
ECM.Go to step 6.
6 CHECK POOR CONTACT.Is there poor contact in engine
speed signal circuit?Repair the poor
contact.Go to step 7.
7 CONFIRM DTC P0725.
Replace the ECM with a new one. Does the DTC appear again,
after memory has been
cleared?Replace the TCM.
trol Module
(TCM).>Replace the ECM.
Engine Control
Module (ECM).> Step Check Yes No
Page 2638 of 2870
4AT(H4DOTC)-62
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
M: DTC P0736 REVERSE INCORRECT RATIO
DTC DETECTING CONDITION:
Vehicle speed sensor malfunction and torque converter turbine speed sensor malfunction, etc. or control
valve malfunction.
TROUBLE SYMPTOM:
Shift point is too high or too low.
Excessive shift shock.
Tight corner “braking” phenomenon.
Gear is not shifted to reverse.
Gear position is held by fail safe function.
Step Check Yes No
1 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 2.Go to step 5.
2 CHECK ACCELERATOR PEDAL POSITION
SENSOR.
1) Connect the Subaru Select Monitor to data
link connector.
2) Turn the ignition switch to ON.
3) Read the value of accelerator pedal posi-
tion sensor on Subaru Select Monitor.Does the value of accelerator
pedal position sensor change
from 0% to 100% smoothly
when throttle was operated from
fully closing to fully opening?Go to step 3.Check accelerator
pedal position sen-
sor.
DTC P1708
THROTTLE POSI-
TION SENSOR
CIRCUIT LOW
INPUT, Diagnostic
Procedure with
Diagnostic Trou-
ble Code (DTC).>
3 CHECK FRONT VEHICLE SPEED SENSOR.
1) Lift-up the vehicle and place rigid racks.
2) Start the engine.
3) Move the select lever “D” range and slowly
increase vehicle speed.
NOTE:
The speed difference between front and rear
wheels may light ABS warning light, but this indi-
cates no malfunction. When AT control diagnosis
is finished, perform the ABS memory clearance
procedure of on-board diagnostics system.Does the vehicle speed dis-
played by Subaru Select Moni-
tor almost correspond with
vehicle speed indicated by
combination meter?Go to step 4.Check the front
vehicle speed sen-
sor.
4 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR.
1) Move the select lever to “P” or “N” range.
2) Idle the engine.Does the turbine speed sen-
sor revolution displayed by
Subaru Select Monitor almost
correspond with engine revolu-
tion indicated by tachometer?There are mal-
functions in TCM,
TCM connector
poor contact or
transmission
assembly mechan-
ical malfunction.Check the torque
converter turbine
speed sensor cir-
cuit.
5 CHECK ACCELERATOR PEDAL POSITION
SENSOR.
1) Turn the ignition switch to ON.
2) Fully close the throttle.
3) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B55) No. 19 (+) — Chassis ground (
−):Is the voltage 0.8 — 1.2 V? Go to step 6.Check the acceler-
ator pedal position
sensor circuit.
DTC P1708
THROTTLE POSI-
TION SENSOR
CIRCUIT LOW
INPUT, Diagnostic
Procedure with
Diagnostic Trou-
ble Code (DTC).>
Page 2640 of 2870
4AT(H4DOTC)-64
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
N: DTC P0741 TORQUE CONVERTER CLUTCH CIRCUIT PERFORMANCE OR
STUCK OFF
DTC DETECTING CONDITION:
Lock up clutch malfunction
Locking of valve
TROUBLE SYMPTOM:
Lock up is not operated.
Step Check Yes No
1 CHECK LOCK UP DUTY SOLENOID CIR-
CUIT.
Check according as DTC P0743 procedure.Is there malfunction? Repair or replace
the lock up duty
solenoid circuit.Go to step 2.
2 CHECK INHIBITOR SWITCH CIRCUIT.
Check according as DTC P0705 procedure.Is there malfunction? Repair or replace
the inhibitor switch
circuit.Go to step 3.
3 CHECK STOP LIGHT SWITCH CIRCUIT.
Check according as DTC P0719 and DTC
P0724 procedure.Is there malfunction? Repair or replace
the stop light
switch circuit.Go to step 4.
4 CHECK ATF TEMPERATURE SENSOR CIR-
CUIT.
Check according to DTC P0712 and DTC
P0713 procedure.Is there malfunction? Repair or replace
the ATF tempera-
ture sensor circuit.Go to step 5.
5 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 6.Go to step 9.
6 CHECK ACCELERATOR PEDAL POSITION
SENSOR.
1) Connect the Subaru Select Monitor to data
link connector.
2) Turn the ignition switch to ON.
3) Read the value of accelerator pedal posi-
tion sensor on Subaru Select Monitor display.Does the value of accelerator
pedal position sensor change
from 0% to 100% smoothly
when throttle was operated from
fully closing to fully opening?Go to step 7.Check the acceler-
ator pedal position
sensor circuit.
7 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR.
1) Move the select lever to “P” or “N” range.
2) Idle the engine.Does the turbine revolution dis-
played by Subaru Select Moni-
tor almost correspond with
engine revolution indicated by
tachometer?Go to step 8.Check the torque
converter turbine
speed sensor cir-
cuit.
8 CHECK ENGINE SPEED SIGNAL.
Idle the engine.Does the turbine revolution dis-
played by Subaru Select Moni-
tor almost correspond with
engine revolution indicated by
tachometer?There is malfunc-
tion in TCM, TCM
connector poor
contact or trans-
mission assembly
mechanical mal-
fuction.Check the engine
speed signal cir-
cuit.
9 CHECK ACCELERATOR PEDAL POSITION
SENSOR.
Check according to DTC P1708, DTC 1709
and DTC P1714 procedure.Is there a malfunction? Go to step 10.Repair or replace
the accelerator
pedal position sen-
sor circuit.
10 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR.
Check according to DTC P0715 procedure.Is there a malfunction? Go to step 11.Repair or replace
the torque converter
turbine speed sen-
sor circuit.
11 CHECK ENGINE SPEED SIGNAL.
Check according to DTC P0725 procedure.Is there a malfunction? Repair or replace
the engine speed
signal circuit. There is malfunc-
tion in TCM, TCM
connector poor
contact or trans-
mission assembly
mechanical mal-
function.
Page 2642 of 2870
4AT(H4DOTC)-66
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
3 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness connector
between TCM connector and chassis ground.
Connector & terminal
(B56) No. 5 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 4.Repair the short
circuit in harness
between TCM and
transmission con-
nector.
4 CHECK LOCK-UP DUTY SOLENOID.
Measure the resistance between transmission
connector receptacle’s terminals.
Connector & terminal
(T4) No. 12 — No. 19:Is the resistance 2.0 — 4.5 Ω? Go to step 5.Go to step 11.
5 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 8.Go to step 6.
6 CHECK OUTPUT SIGNAL EMITTED FROM
TCM.
1) Connect the connectors to TCM and trans-
mission.
2) Lift-up the vehicle and place rigid racks.
NOTE:
Raise all wheels off ground.
3) Start the engine and warm-up the engine
until ATF temperature is above 80°C (176°F).
NOTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
4) Shift the select lever to “D” range and
slowly increase vehicle speed to 60 km/h
(37 MPH).
NOTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When AT control diag-
nosis is finished, perform the ABS memory
clearance procedure of on-board diagnostics
system.
5) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 5 (+) — Chassis ground (
−):Is the voltage more than 10.5
V?Go to step 7.Go to step 10.
7 CHECK OUTPUT SIGNAL FROM TCM.
1) Return the engine to idling speed and shift
select lever to “N” range.
2) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 5 (+) — Chassis ground (
−):Is the voltage less than 1 V? Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in TCM and
transmission.Go to step 10. Step Check Yes No
Page 2643 of 2870
4AT(H4DOTC)-67
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
8 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
1) Connect the connectors to TCM and trans-
mission.
2) Lift-up the vehicle and place rigid racks.
N
OTE:
Raise all wheels off ground.
3) Connect the Subaru Select Monitor to data
link connector.
4) Start the engine and turn Subaru Select
Monitor switch to ON.
5) Start the engine and warm-up the engine
until ATF temperature is above 80°C (176°F).
N
OTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
6) Read the data of lock-up duty solenoid
using Subaru Select Monitor.
Lock-up duty solenoid is indicated in “%”.
7) Shift the select lever to “D” range and
slowly increase vehicle speed to 60 km/h
(37 MPH). Wheels will lock-up.
NOTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When AT control diag-
nosis is finished, perform the ABS memory
clearance procedure of on-board diagnostics
system.
9 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
Return the engine to idling speed and shift
select lever to “N” range, read the data.
N
OTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When AT control diag-
nosis is finished, perform the ABS memory
clearance procedure of on-board diagnostics
system.
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in TCM and
transmission.Go to step 10.
10 CHECK POOR CONTACT.Is there poor contact in lock-up
duty solenoid circuit?Repair poor con-
tact.Replace the TCM.
trol Module
(TCM).> Step Check Yes No
Page 2646 of 2870
4AT(H4DOTC)-70
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
4 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 7.Go to step 5.
5 CHECK OUTPUT SIGNAL FROM TCM.
1) Connect all connectors.
2) Start the engine and warm-up the engine
until ATF temperature is above 80°C (176°F).
N
OTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
3) Turn the ignition switch to ON (engine
OFF).
4) Shift the select lever to “R” range.
5) Close the throttle fully.
6) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 20 (+) — Chassis ground (
−):Is the voltage 5.0 — 7.0 V? Go to step 6.Go to step 9.
6 CHECK OUTPUT SIGNAL FROM TCM.
1) Open the throttle fully.
2) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 20 (+) — Chassis ground (
−):Is the voltage 3.0 — 5.0 V? Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in transmission.Go to step 9.
7 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
1) Connect the connectors to TCM and trans-
mission.
2) Connect the Subaru Select Monitor to data
link connector.
3) Start the engine and turn Subaru Select
Monitor switch to ON.
4) Warm-up the transmission until ATF tem-
perature is above 80°C (176°F).
NOTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
5) Stop the engine and turn ignition switch to
ON (engine OFF).
6) Shift the select lever to “R” range.
7) Read the data of line pressure linear sole-
noid using Subaru Select Monitor.
Line pressure linear solenoid is indicated in
“%”.
8) Throttle is fully closed.Is the value 45 — 50%? Go to step 8.Go to step 9. Step Check Yes No
Page 2647 of 2870
4AT(H4DOTC)-71
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
8 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
1) Fully open the throttle.
2) Shift the select lever to “R” range. (engine
OFF)
3) Read the data of line pressure linear sole-
noid.Is the value 20 — 40%? Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in transmission.Go to step 9.
9 CHECK POOR CONTACT.Is there poor contact in line
pressure linear solenoid cir-
cuit?Repair the poor
contact.Replace the TCM.
trol Module
(TCM).>
10 CHECK LINE PRESSURE LINEAR SOLE-
NOID (IN TRANSMISSION).
1) Remove the transmission connector from
bracket.
2) Drain the ATF.
CAUTION:
Do not drain the ATF until it cools down.
3) Remove the oil pan, and disconnect con-
nector from line pressure linear solenoid.
4) Measure the resistance between line pres-
sure linear solenoid connector and transmis-
sion ground.
Connector & terminal
(AT11) No. 2 — No. 4:Is the resistance 2.0 — 4.5 Ω? Go to step 11.Replace the con-
trol valve body.
Body.>
11 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND LINE PRESSURE LIN-
EAR SOLENOID.
Measure the resistance of harness between
line pressure linear solenoid and transmission
connector.
Connector & terminal
(T4) No. 2 — (AT11) No. 4:
(T4) No. 1 — (AT11) No. 2:Is the resistance less than 1
Ω?Go to step 12.Repair the open cir-
cuit in harness
between line pres-
sure linear solenoid
and transmission
connector.
12 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND LINE PRESSURE LIN-
EAR SOLENOID.
Measure the resistance of harness between
transmission connector and transmission
ground.
Connector & terminal
(T4) No. 1 — Transmission ground:
(T4) No. 2 — Transmission ground:Is the resistance more than 1
MΩ?Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in line pressure
linear solenoid and
transmission.Repair the short
circuit in harness
between line pres-
sure linear sole-
noid and
transmission con-
nector. Step Check Yes No
Page 2649 of 2870
4AT(H4DOTC)-73
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM connector and transmission ground.
Connector & terminal
(B56) No. 9 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 3.Repair the short
circuit in harness
between TCM and
transmission con-
nector.
3 CHECK LOW CLUTCH DUTY SOLENOID.
Measure the resistance between transmission
connector terminals.
Connector & terminal
(T4) No. 4 — No. 20:Is the resistance 2.0 — 4.5 Ω? Go to step 4.Go to step 10.
4 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 7.Go to step 5.
5 CHECK OUTPUT SIGNAL FROM TCM.
1) Connect all connectors.
2) Start the engine and warm-up the engine
until ATF temperature is above 80°C (176°F).
N
OTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
3) Turn the ignition switch to ON (engine
OFF).
4) Shift the select lever to “P” or “N” range.
5) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 9 (+) — Chassis ground (
−):Is the voltage more than 10.5
V?Go to step 6.Go to step 9.
6 CHECK OUTPUT SIGNAL FROM TCM.
1) Shift the select lever to “D” range.
2) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 9 (+) — Chassis ground (
−):Is the voltage less than 1 V? Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in transmission.Go to step 9. Step Check Yes No
Page 2650 of 2870
4AT(H4DOTC)-74
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
7 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
1) Connect the connectors to TCM and trans-
mission.
2) Connect the Subaru Select Monitor to data
link connector.
3) Start the engine and turn Subaru Select
Monitor switch to ON.
4) Warm-up the transmission until ATF tem-
perature is above 80°C (176°F).
N
OTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
5) Stop the engine and turn ignition switch to
ON (engine OFF).
6) Shift the select lever to “P” or “N” range.
7) Read the data of low clutch duty solenoid
using Subaru Select Monitor.
Low clutch duty solenoid is indicated in “%”.Is the value 100%? Go to step 8.Go to step 9.
8 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
1) Turn the ignition switch to ON (engine
OFF).
2) Shift the select lever to “D” range.
3) Read the data of low clutch duty solenoid.Is the value 0%? Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in transmission.Go to step 9.
9 CHECK POOR CONTACT.Is there poor contact in low
clutch duty solenoid circuit?Repair the poor
contactReplace the TCM.
trol Module
(TCM).>
10 CHECK LOW CLUTCH DUTY SOLENOID (IN
TRANSMISSION).
1) Remove the transmission connector from
bracket.
2) Drain the ATF.
CAUTION:
Do not drain the ATF until it cools down.
3) Remove the oil pan, and disconnect con-
nector from low clutch duty solenoid.
4) Measure the resistance between low clutch
duty solenoid connector and transmission
ground.
Connector & terminal
(AT12) No. 2 — Transmission ground:Is the resistance 2.0 — 4.5 Ω? Go to step 11.Replace the con-
trol valve body.
Body.>
11 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND LOW CLUTCH DUTY
SOLENOID.
Measure the resistance of harness between
low clutch duty solenoid and transmission con-
nector.
Connector & terminal
(T4) No. 4 — (AT12) No. 2:Is the resistance less than 1
Ω?Go to step 12.Repair the open
circuit in harness
between low clutch
duty solenoid and
transmission con-
nector. Step Check Yes No