Subaru Legacy III (2000-2003 year). Service manual — part 951

IDI-4

INSTRUMENTATION/DRIVER INFO

COMBINATION METER SYSTEM

2. Combination Meter System

A: SCHEMATIC

1. COMBINATION METER

<Ref. to WI-126, SCHEMATIC, Combination Meter.>

2. OUTSIDE TEMPERATURE INDICATOR

<Ref. to WI-279, SCHEMATIC, Outside Temperature Display System.>

B: INSPECTION

CAUTION:
• When measuring voltage and resistance of the ECM, TCM, or each sensor, use a tapered pin with
a diameter of less than 0.64 mm (0.025 in) in order to avoid poor contact. Do not insert the pin more
than 2 mm (0.08 in).
• Luminescent meter has a CFL (Cold cathode fluorescent light) inverter that generates a high-ten-
sion current. Do not touch the inverter terminal when checking combination meter with ignition
switch turned ON.

1. SYMPTOM CHART

Symptom

Repair order

Reference

Combination meter assembly does not
operate.

(1) Power supply
(2) Ground circuit

<Ref. to IDI-5, CHECK POWER SUPPLY
AND GROUND CIRCUIT, INSPECTION,
Combination Meter System.>

Speedometer does not operate.

(1) (MT) Vehicle speed sensor
(AT) Transmission control module
(2) Harness
(3) Speedometer

MT: <Ref. to IDI-6, CHECK VEHICLE
SPEED SENSOR, INSPECTION, Combi-
nation Meter System.>

AT: <Ref. to IDI-7, CHECK TRANSMIS-
SION CONTROL MODULE, INSPEC-
TION, Combination Meter System.>

Tachometer does not operate.

(1) Engine control module
(2) Harness
(3) Tachometer

<Ref. to IDI-8, CHECK ENGINE CON-
TROL MODULE, INSPECTION, Combi-
nation Meter System.>

Fuel gauge does not operate.

(1) Fuel level sensor
(2) Harness
(3) Fuel gauge

<Ref. to IDI-9, CHECK FUEL LEVEL
SENSOR, INSPECTION, Combination
Meter System.>

Water temperature gauge does not
operate.

(1) Engine coolant temperature sensor
(2) Harness
(3) Water temperature gauge

<Ref. to IDI-11, CHECK ENGINE COOL-
ANT TEMPERATURE SENSOR,
INSPECTION, Combination Meter Sys-
tem.>

Outside temperature indicator does not
operate.

(1) Ambient sensor
(2) Harness
(3) Combination meter

<Ref. to IDI-12, CHECK OUTSIDE TEM-
PERATURE INDICATOR, INSPECTION,
Combination Meter System.>

Indicator and warning lights illuminate
normally, but meter characters are not
displayed when turning ignition switch
ON (Luminescent meter).

Combination meter printed circuit

<Ref. to IDI-13, CHECK COMBINATION
METER PRINTED CIRCUIT, INSPEC-
TION, Combination Meter System.>

IDI-5

INSTRUMENTATION/DRIVER INFO

COMBINATION METER SYSTEM

2. CHECK POWER SUPPLY AND GROUND CIRCUIT

Step

Value

Yes

No

1

CHECK POWER SUPPLY FOR COMBINA-
TION METER.
1) Remove combination meter. <Ref. to IDI-

14, REMOVAL, Combination Meter Assem-
bly.>

2) Disconnect combination meter harness

connector.

3) Turn ignition switch to ON.
4) Measure voltage between combination

meter connector and chassis ground.

Connector & terminal

Standard meter:

(i12) No. 3 (+) — Chassis ground (

−−−−

):

Luminiscent meter:

(i10) No. 8 (+) — Chassis ground (

−−−−

):

(i11) No. 5 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Go to step 2.

Check harness for
open or short
between ignition
relay and combi-
nation meter.

2

CHECK POWER SUPPLY FOR COMBINA-
TION METER.
Measure voltage between combination meter
connector and chassis ground.

Connector & terminal

Standard meter:

(i12) No. 7 (+) — Chassis ground (

−−−−

):

Luminiscent meter:

(i10) No. 9 (+) — Chassis ground (

−−−−

):

(i12) No. 1 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the specified
value?

10 V

Go to step 3.

Check harness for
open or short
between fuse and
combination
meter.

3

CHECK GROUND CIRCUIT OF COMBINA-
TION METER.
1) Turn ignition switch to OFF.
2) Measure resistance of harness between

combination meter connector and chassis
ground.

Connector & terminal

Standard meter:

(i10) No. 20 — Chassis ground :

Luminiscent meter:

(i11) No. 7 — Chassis ground:

Is the measured value less than the speci-
fied value?

10

Ω

Go to step 4.

Repair wiring har-
ness.

4

CHECK GROUND CIRCUIT OF COMBINA-
TION METER.
Measure resistance of harness between com-
bination meter connector and chassis ground.

Connector & terminal

Standard meter:

(i11) No. 16 — Chassis ground :

Luminiscent meter:

(i10) No. 18— Chassis ground:

Is the measured value less than the specified
value?

10

Ω

Replace combina-
tion meter.

Repair wiring har-
ness.

IDI-6

INSTRUMENTATION/DRIVER INFO

COMBINATION METER SYSTEM

3. CHECK VEHICLE SPEED SENSOR

Step

Value

Yes

No

1

CHECK VEHICLE SPEED SENSOR.
1) Lift-up the vehicle and support it with safety

stands.

2) Remove the combination meter with har-

ness connector.

3) Drive the vehicle at a speed greater than 20

km/h (12 MPH).

Warning:

Be careful not to get caught in the running
wheels.

4) Measure voltage between combination

meter connector and chassis ground.

Connector & terminal

Standard meter:

(i10) No. 13 (+) — Chassis ground (

−−−−

):

Luminiscent meter:

(i10) No. 11 (+) — Chassis ground (

−−−−

):

Is the measured value same as the speci-
fied value?

0 V

←→

5 V

Check speedome-
ter. <Ref. to IDI-
18, REMOVAL,
Speedometer.>

Go to step 2.

2

CHECK VEHICLE SPEED SENSOR POWER
SUPPLY.
1) Turn ignition switch to OFF.
2) Disconnect vehicle speed sensor harness

connector.

3) Turn ignition switch to ON.
4) Measure voltage between vehicle speed

sensor connector and engine ground.

Connector & terminal

(B17) No. 3 (+) — Engine ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Go to step 3.

Check harness for
open or short
between ignition
relay and vehicle
speed sensor.

3

CHECK HARNESS BETWEEN VEHICLE
SPEED SENSOR AND ENGINE GROUND.
1) Turn ignition switch to OFF.
2) Measure resistance between vehicle speed

sensor connector and engine ground.

Connector & terminal

(B17) No. 2 — Engine ground:

Is the measured value less than the speci-
fied value?

10

Ω

Go to step 4.

Repair wiring har-
ness.

4

CHECK HARNESS BETWEEN VEHICLE
SPEED SENSOR AND COMBINATION
METER.
1) Disconnect connector from combination

meter.

2) Measure resistance between vehicle speed

sensor harness connector and combination
meter harness connector.

Connector & terminal

Standard meter:

(B17) No. 1 — (i10) No. 13:

Luminiscent meter:

(B17) No. 1 — (i10) No. 11:

Is the measured value less than the speci-
fied value?

10

Ω

Replace vehicle
speed sensor.

Repair wiring har-
ness.

IDI-7

INSTRUMENTATION/DRIVER INFO

COMBINATION METER SYSTEM

4. CHECK TRANSMISSION CONTROL MODULE

Step

Value

Yes

No

1

CHECK TRANSMISSION CONTROL MOD-
ULE SIGNAL.
1) Lift-up the vehicle and support it with safety

stands.

2) Drive the vehicle faster than 10 km/h (6

MPH).

Warning:

Be careful not to get caught in the running
wheels.

3) Measure voltage between transmission

control module connector and chassis
ground.

Connector & terminal

(B56) No. 17 (+) — Chassis ground (

−−−−

):

Is the measured value same as the speci-
fied value?

0 V

←→

5 V

Go to step 2.

Check transmis-
sion control mod-
ule. <Ref. to AT-2,
Basic Diagnostic
Procedure.>

2

CHECK HARNESS BETWEEN TRANSMIS-
SION CONTROL MODULE AND COMBINA-
TION METER.
1) Turn ignition switch to OFF.
2) Disconnect connector from transmission

control module and combination meter.

3) Measure resistance between transmission

control module harness connector and
combination meter harness connector.

Connector & terminal

Standard meter:

(B56) No. 17 — (i10) No. 13:

Luminiscent meter:

(B56) No. 17 — (i10) No. 11:

Is the measured value less than the speci-
fied value?

10

Ω

Check speed
meter. <Ref. to
IDI-18,
REMOVAL,
Speedometer.>

Repair wiring har-
ness.