1996 SUBARU LEGACY Fuel system

2_7
[T10BW0]
ON-BOARD
DIAGNOSTICS
II
SYSTEM

10
.
Diagnostics
Chart
with
Trouble
Code

OBD
(FBI)

P1402


H2M1411

BW
:
DTC
P1402

-
FUEL
LEVEL
SENSOR
CIRCUIT

MALFUNCTION
(FLVL)
-

DTC
DETECTING
CONDITION
:

Two
consecutive
trips
with
fault

108W1
Checkspeedometer
and
tachometer

operation
in
combination
meter
.

Check
ground
circuit
of
combination

meter
.

108W3

Check
inputsignal
for
ECM
.
(Using

voltage
meter
andSubaru
Select

Monitor
.)

10BW4
Check
fuel
level
sensor
.

10BW5
Check
fuel
sub
level
sensor
.

10BW6
Check
harness
between
fuel
pump
and

fuel
sub
meter
unit
connector
.

10BW7
Check
ground
circuit
of
fuel
level
sensor
.

Check
harnessbetween
ECM
and
fuel

pump
connector
.

10BW9

Check
harnessbetween
ECM,

combination
meter
and
fuel
pump

connector
.

10BW10
Check
harness
between
combination

meter
and
fuel
pump
connector
.

108W11
Check
combination
meter
.

CAUTION
:

After
repair
or
replacement
of
faulty
parts,
conduct

CLEAR
MEMORY
and
INSPECTION
MODES
.

<
Ref
.
to
2-7[T3D0]
and
[T3E0]
.*2
and
*4
>

46

ON-BOARD
DIAGNOSTICS
II
SYSTEM
[TloBw2i
2-7
10
.
Diagnostics
Chart
with
Trouble
Code

WIRING
DIAGRAM
:

a
:
QD
Combination
b
:
i12
meter
Ignition
c
:
i14
No
.
15W2
switch
SBF-4
FL1
.25B

Fuel
gauge

S
.M
.J
.

O
O
E
E)
El)

Fuel
pumpASSY

R58
Fuel
level
sensor

Junction
A

R15R57

ECM
~
Fuel
sub
meter
unit

Fuel
sub
O
~p
level
sensor

E

822

R57
872
R59

1
5
1
6
1
7
1
8
'
,

O
,'
IyWJJ
LJJJ
LJJ

u
4u
1Ju
i10
i~2
117118119~2
.0121122123V4
.
.
.
.
.
.
(D

1
1
1
141
141EIb1

B2M1021

CHECK
SPEEDOMETER
AND
TACHOMETER

(OPERATION
IN
COMBINATION
METER
.

CHECK
:
Does
speedometer
and
tachometer
operate

normally?

vES
:
Go
to
step
10BW3
.

No
:
Go
to
step
10BW2
.

10BW2
I
CHECK
GROUND
CIRCUIT
OFCOMBINA-

TION
METER
.

1)
Turn
ignition
switch
to
OFF
.

2)
Pull
out
combination
meter
from
instrument
panel
.

<
Ref
.
to
6-2
[W13A1
]
.*1
>

3)
Disconnect
connector
from
combination
meter
.

47

ON-BOARD
DIAGNOSTICS
II
SYSTEM
[r1oBwa]
2-7

10
.
Diagnostics
Chart
with
Trouble
Code

FLEVEL
(F45)

2
.50V

H2M1327

3
2
1
5
4

D

S2

B2M0935
I

CHECK
:
Does
the
value
change
less
than
0
.12
Vby

shaking
harness
and
connector
of
ECM
while

monitoring
the
value
with
Subaru
Select

Monitor?

9
Subaru
Select
Monitor
Designate
mode
using
function
key
.

Function
mode
:
F45

9
F45
:
Fuel
level
sensor
output
signal
is
indicated
.

,rES
:
Repair
poor
contact
in
ECM
connector
.

No
:
Even
if
MIL
lights
up,
the
circuit
has
returned
to

a
normal
condition
at
this
time
.
A
temporary
poor

contact
of
the
connector
may
be
the
cause
.

NOTE
:

In
this
case,
repair
the
following
:

"
Poor
contact
in
fuel
pump
connector

"
Poor
contact
in
combination
meter
connector

"
Poor
contact
in
ECM
connector

"
Poor
contact
in
coupling
connector
(i3,
1322,
B97and

R57)

10BW4
CHECK
FUEL
LEVEL
SENSOR
.

1)
Turn
ignition
switch
to
OFF
.

2)
Remove
fuel
pump
access
hole
lid
located
on
the
right

rear
of
luggage
compartment
floor
.

3)
Disconnect
connector
from
fuel
pump
.

4)
Measure
resistance
between
connector
terminals
of
fuel
pump
.

CHECK
:
Terminals

No
.
3
-
No
.
5
:

Is
the
resistance
less
than
100
S2?

vES
:
Go
to
step
10BW5
.

No
:
Replace
fuel
sending
unit
.

49

2-7
[T10BW5]
ON-BOARD
DIAGNOSTICS
II
SYSTEM

10
.
Diagnostics
Chart
with
Trouble
Code

[2-
1

B2MO9361

R
1
2
34
5

.0
Q
0
.

B2MO937A

I
10BW5
CHECK
FUEL
SUB
LEVEL
SENSOR
.

1)
Remove
service
hole
cover
located
on
the
left
rear
of

luggage
compartment
floor
.

2)
Disconnect
connector
from
fuel
sub
meter
unit
.

3)
Measure
resistance
between
connector
terminals
of
fuel
sub
meter
unit
.

CHECK
;
Terminals

No
.
1
-
No
.
2
:

Is
the
resistance
less
than
100
SZ?

,rES
:
Go
to
step
10BW6
.

No
:
Replace
fuel
sub
meter
unit
.

10BW6
CHECK
HARNESS
FUEL
PUMP
I
I
AND
FUEL
SUB
MET
RWUNIT
CONNECTOR
.

Measure
resistance
of
harness
between
fuel
pump
and

fuel
sub
meter
unit
connector
.

CHECK
:
Connector
&
terminal

(R58)
No
.
3
-
(R59)
No
.
2
:

Is
the
resistance
less
than
1
SZ?

0
:
Go
to
step
10BW7
.

No
:
Repair
open
circuit
in
harness
between
fuel
pump

and
fuel
sub
meter
unit
connector
.

50

ON-BOARD
DIAGNOSTICS
11
SYSTEM
[TIoBwB]
2-7
10
.
DiagnosticsChart
with
Trouble
Code

R58

B2M0938A
I

R58

B2M0939A
I

10BW7
CHECK

I
SENSOR
.

ROUND
CIRCUIT
OF
FUEL
LEVEL

Measure
resistance
of
harness
between
fuel
pump
con-

nector
and
chassis
ground
.

CHECK
:
Connector
&
terminal
(R58)
No
.
5
-
Chassis
ground
:

Is
the
resistance
less
than
5
92?

YES
:
Go
to
step
10BW8
.

No
:
Repair
harness
and
connector
.

NOTE
:

In
this
case,
repair
the
following
:

9
Open
circuit
in
harness
between
fuel
pump
connector

and
chassis
grounding
terminal

"
Poor
contact
in
fuel
pump
connector

"
Poor
contact
in
coupling
connectors
(R57,
B97and

B22)

1OBW8
CHECK
HARNESS

(FUEL
PUMP
CONNECTOREN

ECM
AND

1)
Connect
connector
to
fuel
sub
meter
unit
.

2)
Turn
ignition
switch
to
ON
.

3)
Measure
voltage
between
fuel
pump
connector
and

chassis
ground
.

CHECK
:
Connector
&
terminal
(R58)
No
.
3
(+)
-
Chassis
ground
(
)
:

Is
thevoltage
less
than
1
V?

Repair
harness
and
connector
.

NOTE
:

In
this
case,
repair
the
following
:

*
Open
circuit
in
harness
between
fuel
pump
connector

and
junction
A
on
rear
wiring
harness

"
Poor
contact
in
fuel
sub
meter
unit
connector

"
Poor
contact
in
fuel
pump
connector

"
Poor
contact
in
coupling
connector
(R57)

No
:
Go
to
nextstep
4)

51

2-7
[T10BW9]
ON-BOARD
DIAGNOSTICS
II
SYSTEM

10
.
Diagnostics
Chart
with
Trouble
Code

'-
'lam

o
-
-

-`
=1~\
~--
~
~
o

(D
--

.
G2M0340

R58

B2M0940A
I

4)
Turn
ignition
switch
to
OFF
.

5)
Disconnect
connector
from
ECM
.

6)
Turn
ignition
switch
to
ON
.

7)
Measure
voltage
between
ECM
connector
and
chassis

ground
.

CHECK
:
Connector
&
terminal

(B84)
No
.
27
(+)
-
Chassis
ground
:

Is
thevoltage
less
than
1
V?

vES
:
Repair
harness
and
connector
.

NOTE
:

In
this
case,
repair
the
following
:

9
Open
circuit
in
harness
between
ECM
connector
and

junction
A
on
rear
wiring
harness

9
Poor
contact
in
coupling
connector
(B97)

No
:
Repair
connector
.

NOTE
:

In
this
case,
repairthe
following
:

"
Poor
contact
in
fuel
pump
connector

"
Poor
contact
in
fuel
sub
meter
unit

"
Poor
contact
in
ECM
connector

CHECK
HARNESSBETWEEN
ECM,
COMBI-

10BW9
NATION
METER
AND
FUEL
PUMP
CONNEC-

TOR
.

1)
Turn
ignition
switch
to
OFF
.

2)
Remove
fuel
pump
access
hole
lid
located
on
the
right

rear
of
luggage
compartment
floor
.

3)
Disconnect
connector
from
fuel
pump
.

4)
Measure
resistance
of
harness
between
fuel
pump

connector
and
chassis
ground
.

CHECK
:
Connector
&
terminal
(R58)
No
.
3
-
Chassis
ground
:

Is
the
resistance
less
than10
S2?

vES
:
Go
to
nextstep
5)
.

No
:
Go
to
step
10BW10
.

5)
Remove
service
hole
cover
located
on
the
left
rear
of

luggage
compartment
floor
.

52

ON-BOARD
DIAGNOSTICS
II
SYSTEM
[TIoBw9]
2-7

10
.
DiagnosticsChart
with
Trouble
Code

R58

B2M0940A
I

R59

82M0941A
I

R15

B2M0942A
I

6)
Disconnect
connector
from
fuel
sub
meter
unit
.

7)
Measure
resistance
of
harness
between
fuel
pump

connector
and
chassis
ground
.

CHECK
:
Connector
&
terminal

(R58)
No
.
3
-
Chassis
ground
:

Is
the
resistance
less
than
10
92?

YES
:
Repair
short
circuit
in
harness
between
fuel
pump

and
fuel
sub
meter
unit
connector
.

No
:
Go
to
nextstep
8)
.

8)
Separate
fuel
tank
cord
connector
(R57)
and
rear
wir-

ing
harness
connector
(R15)
.

9)
Measure
resistance
of
harness
between
fuel
sub
meter

unit
connector
and
chassis
ground
.

CHECK
:
Connector
&
terminal

(R59)
No
.
1
-
Chassis
ground
:

Is
the
resistance
less
than10
S2?

,rES
:
Repair
short
circuit
in
fuel
tankcord
.

No
:
Go
to
nextstep
10)
.

10)
Separate
rear
wiring
harness
connector
(R1)
and

bulkhead
wiring
harness
connector
(B97)
.

11)
Measure
resistance
of
harness
between
rear
wiring

harnessconnector
and
chassis
ground
.

CHECK
:
Connector
&
terminal

(R15)
No
.
3
-
Chassis
ground
:

Is
the
resistance
less
than10
0?

,rES
:
Repair
short
circuit
in
rear
wiring
harness
.

No
:
Go
to
nextstep
12)
.

12)
Measure
resistance
of
harness
between
bulkhead
wir-

ing
connector
and
chassis
ground
.

CHECK
:
Connector
&
terminal

(B97)
No
.
J2
-
Chassis
ground
:

Is
the
resistance
less
than10
S2?

,rES
:
Go
to
nextstep
13)
.

No
:
Repair
short
circuit

and
ECM
connector
.

in
harness
between
S
.M
.J
.

13)
Separate
bulkhead
wiring
harness
connector
(B38)

and
instrument
panel
wiring
harness
connector
(i3)
.

14)
Measure
resistance
of
harness
between
bulkhead
wir-

ing
harness
connector
and
chassis
ground
.

CHECK
;
Connector
&
terminal

(B97)
No
.
J2
-
Chassis
ground
:

Is
the
resistance
less
than10
SZ?

vES
:
Repair
short
circuit
in
bulkhead
wiring
harness
.

No
:
Repair
short
circuit
in
instrument
panel
wiring

harness
.

53

2-7
frioBwio]
ON-BOARD
DIAGNOSTICS
II
SYSTEM

10
.
Diagnostics
Chart
with
Trouble
Code

10BW10
I
CHECK
HARNESSBETWEEN
COMBINATION

METER
AND
FUEL
PUMP
CONNECTOR
.

1)
Connect
connector
tofuel
pump
.

2)
Pull
out
combination
meterfrom
instrument
panel
.

<
Ref
.
to
6-2
[W13A1
]
.*1
>

3)
Disconnect
connector
from
combination
meter
.

4)
Measure
resistanceof
harness
between
combination

meter
connector
and
chassis
ground
.

CHECK
:
Connector
&
terminal

(i10)
No
.
3
-
Chassis
ground
:

Is
the
resistance
less
than
200
SZ?

Go
to
step
10BW11
.

No
:
Repair
harness
and
connector
.

NOTE
:

In
this
case,
repair
the
following
:

Open
circuit
in
harness
between
combination
meter

connector
and
junction
A
on
rearwiring
harness

*
Poor
contact
in
coupling
connectors
(i3
and
1397)

10BW11
I
CHECK
COMBINATION
METER
.

1)
Disconnect
speedometer
cablefrom
combination

meter
and
remove
combination
meter
.

CHECK
:
Is
the
fuel
meter
installation
screw
tightened

securely?

,rES
:
Go
to
nextstep
2)
.

No
:
Tighten
fuel
meter
installation
screw
securely
.

2)
Remove
printed
circuit
plate
assemblyfrom
combina-

tion
meter
assembly
.

CHECK
:
Is
there
flaw
or
burning
on
printed
circuit

plate
assembly?

YES
:
Replace
printed
circuit
plate
assembly
.

No
:
Replace
fuel
meter
assembly
.

54