Subaru 2001 IMPREZA User manual

FUJI HEAVY INDUSTRIES LTD. G1830GE5
2001 IMPREZA SERVICE MANUAL QUICK REFERENCE INDEX
CHASSIS SECTION
This service manual has been prepared
to provide SUBARU service personnel
with the necessary information and data
for the correct maintenance and repair
of SUBARU vehicles.
This manual includes the procedures
for maintenance, disassembling, reas-
sembling, inspection and adjustment of
components and diagnostics for guid-
ance of experienced mechanics.
Please peruse and utilize this manual
fully to ensure complete repair work for
satisfying our customers by keeping
their vehicle in optimum condition.
When replacement of parts during
repair work is needed, be sure to use
SUBARU genuine parts.
All information, illustration and specifi-
cations contained in this manual are
based on the latest product information
available at the time of publication
approval.
FRONT SUSPENSION FS
REAR SUSPENSION RS
WHEEL AND TIRE SYSTEM WT
DIFFERENTIALS DI
TRANSFER CASE TC
DRIVE SHAFT SYSTEM DS
ABS ABS
ABS (DIAGNOSTICS) ABS
BRAKE BR
PARKING BRAKE PB
POWER ASSISTED SYSTEM
(POWER STEERING) PS

ABS (DIAGNOSTICS) ABS
Page
1. Basic Diagnostic Procedure........................................................................2
2. Check List for Interview...............................................................................6
3. General Description ....................................................................................9
4. Electrical Components Location................................................................12
5. Control Module I/O Signal.........................................................................14
6. Subaru Select Monitor...............................................................................18
7. Read Diagnostic Trouble Code.................................................................20
8. Inspection Mode........................................................................................21
9. Clear Memory Mode..................................................................................22
10. ABS Warning Light Illumination Pattern....................................................23
11. List of Diagnostics Trouble Code..............................................................24
12. Diagnostics Chart with Diagnosis Connector............................................28
13. Diagnostics Chart with Subaru Select Monitor..........................................96
14. General Diagnostics Table......................................................................186

ABS-2
ABS (DIAGNOSTICS) BASIC DIAGNOSTIC PROCEDURE
1. Basic Diagnostic Procedure
A: PROCEDURE
1. WITHOUT SUBARU SELECT MONITOR
CAUTION:
Remove foreign matter (dust, water, etc.) from the ABSCM&H/U connector during removal and instal-
lation.
NOTE:
•To check harness for broken wires or short circuits, shake it while holding it or the connector.
•When ABS warning light illuminates, read and record trouble code indicated by ABS warning light.
Step Check Yes No
1 CHECK PRE-INSPECTION.
1)Ask the customer when and how the trouble
occurred using interview checklist. <Ref. to
ABS-6, Check List for Interview.>
2)Before performing diagnosis, inspect unit
which might influence the ABS problem. <Ref.
to ABS-9, INSPECTION, General Descrip-
tion.>
Is unit that might influence the
ABS problem normal? Go to step 2. Repair or replace each unit.
2 CHECK INDICATION OF TROUBLE CODE.
Calling up trouble code. <Ref. to ABS-20,
Read Diagnostic Trouble Code.>
Is trouble code readable? Go to step 3. Inspect using diag-
nostic chart for
ABS warning light
failure.<Ref. to
ABS-28, Diagnos-
tics Chart with
Diagnosis Con-
nector.>
NOTE:
Call up trouble
code again after in-
specting ABS
warning light.
<Ref. to ABS-20,
Read Diagnostic
Trouble Code.>
3 CHECK TROUBLE CODE.
NOTE:
Record all trouble codes.
Is only the start code issued? Go to step 4. Go to step 5.
4 PERFORM THE GENERAL DIAGNOSTICS.
1)Inspect using “General Diagnostics Table”.
<Ref. to ABS-186, General Diagnostics Table.>
2)Perform the clear memory mode. <Ref. to
ABS-22, WITHOUT SUBARU SELECT MONI-
TOR, OPERATION, Clear Memory Mode.>
3)Perform the inspection mode. <Ref. to ABS-
21, Inspection Mode.>
Calling up the trouble code. <Ref. to ABS-20,
Read Diagnostic Trouble Code.>
Is only the start code issued? Complete the
diagnosis. Go to step 5.

ABS-3
ABS (DIAGNOSTICS)
BASIC DIAGNOSTIC PROCEDURE
5 PERFORM THE DIAGNOSIS.
1)Inspect using “Diagnostics Chart with Diag-
nostic Connector”.<Ref. to ABS-28, Diagnos-
tics Chart with Diagnosis Connector.>
NOTE:
Fortroublecode list,referto “List of Diagnostics
Trouble Code”.<Ref. to ABS-24, WITHOUT
SUBARU SELECT MONITOR, LIST, List of Di-
agnostics Trouble Code.>
2)Repair trouble cause.
3)Perform the clear memory mode. <Ref. to
ABS-22, WITHOUT SUBARU SELECT MONI-
TOR, OPERATION, Clear Memory Mode.>
4)Perform the inspection mode. <Ref. to ABS-
21, Inspection Mode.>
5)Calling up the trouble code. <Ref. to ABS-20,
Read Diagnostic Trouble Code.>
Is only the start code issued? Complete the
diagnosis. Inspect using “DiagnosticsChart
with Diagnostic
Connector”. <Ref.
to ABS-28, Diag-
nostics Chart with
Diagnosis Con-
nector.>
Step Check Yes No

ABS-4
ABS (DIAGNOSTICS) BASIC DIAGNOSTIC PROCEDURE
2. WITH SUBARU SELECT MONITOR
CAUTION:
Remove foreign matter (dust, water, etc.) from the ABSCM&H/U connector during removal and instal-
lation.
NOTE:
•To check harness for broken wires or short circuits, shake it while holding it or the connector.
•Check list for interview. <Ref. to ABS-26, WITH SUBARU SELECT MONITOR, LIST, List of Diagnostics
Trouble Code.>
Step Check Yes No
1 CHECK PRE-INSPECTION.
1)Ask the customer when and how the trouble
occurred using interview checklist. <Ref. to
ABS-6, Check List for Interview.>
2)Before performing diagnosis, inspect unit
which might influence the ABS problem. <Ref.
to ABS-9, INSPECTION, General Descrip-
tion.>
Is unit that might influence the
ABS problem normal? Go to step 2. Repair or replace each unit.
2 CHECK INDICATION OF TROUBLE CODE
DISPLAY.
1)Turn ignition switch to OFF.
2)Connect the SUBARU SELECT MONITOR
to data link connector.
3)Turn ignition switch to ON and SUBARU
SELECT MONITOR to ON.
NOTE:
If the communication function of the select
monitor cannot be executed normally, check
the communication circuit. <Ref. to ABS-96,
COMMUNICATION FOR INITIALIZING IM-
POSSIBLE, Diagnostics Chart with Subaru Se-
lect Monitor.>
4)Read diagnostic trouble code. <Ref. to ABS-
19, READ CURRENT DATA, OPERATION,
Subaru Select Monitor.>
5)Record all trouble codes and frame data.
Is the corresponding trouble
encoding? Go to step 3. Go to step 4.
3 PERFORM THE GENERAL DIAGNOSTICS.
1)Inspect using “General Diagnostics Table”.
<Ref. to ABS-186, General Diagnostics Table.>
2)Perform the clear memory mode. <Ref. to
ABS-19, CLEAR MEMORY MODE, OPERA-
TION, Subaru Select Monitor.>
3)Perform the inspection mode. <Ref. to ABS-
21, Inspection Mode.>
4)Calling up the trouble code. <Ref. to ABS-18,
READ DIAGNOSTIC TROUBLE CODE,
OPERATION, Subaru Select Monitor.>
Is no trouble code designated
and ABS warning light goes
out after turning on?
Complete the
diagnosis. Go to step 4.

ABS-5
ABS (DIAGNOSTICS)
BASIC DIAGNOSTIC PROCEDURE
4 PERFORM THE DIAGNOSIS.
1)Inspect using “Diagnostics Chart with
Subaru Select Monitor”.<Ref. to ABS-96, Diag-
nostics Chart with Subaru Select Monitor.>
NOTE:
Fortroublecode list,referto “List of Diagnostics
Trouble Code”.<Ref. to ABS-24, WITHOUT
SUBARU SELECT MONITOR, LIST, List of Di-
agnostics Trouble Code.>
2)Repair trouble cause.
3)Perform the clear memory mode. <Ref. to
ABS-19, CLEAR MEMORY MODE, OPERA-
TION, Subaru Select Monitor.>
4)Perform the inspection mode. <Ref. to ABS-
21, Inspection Mode.>
5)Calling up the trouble code. <Ref. to ABS-18,
READ DIAGNOSTIC TROUBLE CODE,
OPERATION, Subaru Select Monitor.>
Is no trouble code designated
and does ABS warning light go
out after turning on?
Complete the
diagnosis. Inspect using “DiagnosticsChart
withSubaruSelect
Monitor”. <Ref. to
ABS-96, Diagnos-
tics Chart with
Subaru Select
Monitor.>
Step Check Yes No

ABS-6
ABS (DIAGNOSTICS) CHECK LIST FOR INTERVIEW
2. Check List for Interview
A: CHECK
Check the following items about the vehicle's state.
1. STATE OF ABS WARNING LIGHT
2. SYMPTOMS
ABS warning light
comes on. ❏Always
❏Sometimes
❏Only once
❏Does not come on
•When / how long does it come on?:
Ignition key position ❏LOCK
❏ACC
❏ON (before starting engine)
❏START
❏On after starting (Engine is running)
❏On after starting (Engine is stop)
Timing ❏Immediately after ignition is ON.
❏Immediately after ignition starts.
❏When advancing km/h to km/h
MPH to MPH
❏While traveling at a constant speed km/h MPH
❏When decelerating km/h to km/h
MPH to MPH
❏When turning to right Steering angle : deg
Steering time : sec
❏When turning to left Steering angle : deg
Steering time : sec
❏When moving other electrical parts
•Parts name :
•Operating condition :
ABS operating condi-
tion ❏Performs no work.
❏Operates only when abruptly applying brakes. Vehicle speed : km/h
MPH
•How to step on brake pedal :
a) Operating time : sec
b) Operating noise : ❏Produce / ❏Does not produce
•What kind of noise? ❏Knock
❏Gong gong
❏Bong
❏Buzz
❏Gong gong buzz
❏Others :
c) Reaction force of brake pedal ❏Stick
❏Press down once with a clunk
❏Press and released
❏Others :

ABS-7
ABS (DIAGNOSTICS)
CHECK LIST FOR INTERVIEW
3. CONDITIONS UNDER WHICH TROUBLE OCCURS
Behavior of vehicle a) Directional stability cannot be obtained or steering arm refuses to work when applying brakes :
❏Yes / ❏No
•When : ❏Vehicle turns to right
❏Vehicle turns to left
❏Spins
❏Others :
b) Directional stability cannot be obtained or steering arm refuses to work when accelerating :
❏Yes / ❏No
•When : ❏Vehicle turns to right
❏Vehicle turns to left
❏Spins
❏Others :
c) Brakes are out of order : ❏Yes / ❏No
•What : ❏Braking distance is long
❏Brakes lock or drag
❏Pedal stroke is long
❏Pedal sticks
❏Others :
d) Poor acceleration : ❏Yes / ❏No
•What : ❏Fails to accelerate
❏Engine stalls
❏Others :
e) Occurrence of vibration : ❏Yes / ❏No
•Where
•What kind :
f) Occurrence of abnormal noise : ❏Yes / ❏No
•Where
•What kind :
g) Occurrence of other phenomena : ❏Yes / ❏No
•What kind :
Environment a) Weather ❏Fine
❏Cloudy
❏Rainy
❏Snowy
❏Various/Others :
b) Ambient temperature °F (°C)
c) Road ❏Urban area
❏Suburbs
❏Highway
❏General road
❏Ascending slope
❏Descending slope
❏Paved road
❏Gravel road
❏Muddy road
❏Sandy place
❏Others :
d) Road surface ❏Dry
❏Wet
❏New-fallen snow
❏Compressed snow
❏Frozen slope
❏Others :

ABS-8
ABS (DIAGNOSTICS) CHECK LIST FOR INTERVIEW
Condition a) Brakes Deceleration : g
❏Continuous / ❏Intermittent
b) Accelerator Acceleration : g
❏Continuous / ❏Intermittent
c) Vehicle speed km/h MPH
❏Advancing
❏Accelerating
❏Reducing speed
❏Low speed
❏Turning
❏Others :
d) Tire inflation pressure Front RH tire : kPa
Front LH tire : kPa
Rear RH tire : kPa
Rear LH tire : kPa
e) Degree of wear Front RH tire :
Front LH tire :
Rear RH tire :
Rear LH tire :
f) Genuine parts are used. : ❏Yes / ❏No
g) Chain is passed around tires. : ❏Yes / ❏No
h) T tire is used. : ❏Yes / ❏No
i) Condition of suspension alignment :
j) Loading state :
k) Repair parts are used. : ❏Yes / ❏No
•What :
l) Others :

ABS-9
ABS (DIAGNOSTICS)
GENERAL DESCRIPTION
3. General Description
A: CAUTION
1. SUPPLEMENTAL RESTRAINT SYSTEM
“AIRBAG”
Airbag system wiring harness is routed near the
ABS sensor, ABS control module and hydraulic
control unit.
CAUTION:
•All Airbag system wiring harness and con-
nectors are colored yellow. Do not use electri-
cal test equipment on these circuit.
•Be careful not to damage Airbag system wir-
ing harness when servicing the ABS sensor,
ABS control module and hydraulic control unit.
B: INSPECTION
Before performing diagnostics, check the following
items which might affect ABS problems:
1. BATTERY
Measure battery voltage and specific gravity of
electrolyte.
Standard voltage: 12 V, or more
Specific gravity: Above 1.260
2. BRAKE FLUID
1) Check brake fluid level.
2) Check brake fluid leakage.
3. HYDRAULIC UNIT
Check the hydraulic unit.
•With brake tester <Ref. to ABS-9, CHECKING
THE HYDRAULIC UNIT ABS OPERATION WITH
BRAKE TESTER, INSPECTION, ABS Control
Module and Hydraulic Control Unit (ABSCM&H/
U).>
•Without brake tester <Ref. to ABS-8, CHECK-
ING THE HYDRAULIC UNIT ABS OPERATION
BY PRESSURE GAUGE, INSPECTION, ABS
Control Module and Hydraulic Control Unit (AB-
SCM&H/U).>
4. BRAKE DRAG
Check brake drag.
5. BRAKE PAD AND ROTOR
Check brake pad and rotor.
•Front <Ref. to BR-24, INSPECTION, Front
Brake Pad.> and <Ref. to BR-27, INSPECTION,
Front Disc Rotor.>
•Rear <Ref. to BR-35, INSPECTION, Rear
Brake Pad.> and <Ref. to BR-38, INSPECTION,
Rear Disc Rotor.> or <Ref. to BR-45, INSPEC-
TION, Rear Drum Brake Shoe.> and <Ref. to BR-
47, INSPECTION, Rear Drum Brake Drum.>
6. TIRE
Check tire specifications, tire wear and air pres-
sure. <Ref. to WT-2, SPECIFICATIONS, General
Description.>

ABS-10
ABS (DIAGNOSTICS) GENERAL DESCRIPTION
C: PREPARATION TOOL
1. SPECIAL TOOLS
2. GENERAL PURPOSE TOOLS
ILLUSTRATION TOOL NUMBER DESCRIPTION REMARKS
24082AA150 CARTRIDGE Troubleshooting for electrical systems.
22771AA030 SELECT MONITOR
KIT Troubleshooting for electrical systems. •English: 22771AA030 (Without printer)
•German: 22771AA070 (Without printer)
•French: 22771AA080 (Without printer)
•Spanish: 22771AA090 (Without printer)
B2M3876
B2M3877
TOOL NAME REMARKS
Circuit tester Used for measuring resistance, voltage and ampere.
Oscilloscope Used for measuring sensor.

ABS-11
ABS (DIAGNOSTICS)
GENERAL DESCRIPTION

ABS-12
ABS (DIAGNOSTICS) ELECTRICAL COMPONENTS LOCATION
4. Electrical Components Location
A: LOCATION
BR0031
(1) ABS control module and hydraulic
control unit (ABSCM&H/U) (5) Data link connector (for Subaru select monitor) (8) ABS sensor
(9) Wheel cylinder
(2) Proportioning valve (6) Transmission control module (only
AT vehicle) (10) G sensor
(3) Diagnosis connector (11) Stop light switch
(4) ABS warning light (7) Tone wheel (12) Master cylinder

ABS-13
ABS (DIAGNOSTICS)
ELECTRICAL COMPONENTS LOCATION
B4M1226B
(4)
BR0032
BR0056 B4M0231E
(5)
BR0033 BR0057
BR0058
( 7 ) ( 8 )

ABS-14
ABS (DIAGNOSTICS) CONTROL MODULE I/O SIGNAL
5. Control Module I/O Signal
A: ELECTRICAL SPECIFICATION
NOTE:
•The terminal numbers in the ABS control module and hydraulic control unit connector are as shown in the
figure.
•When the connector is removed from the ABSCM&H/U, the connector switch closes the circuit between
terminal No. 22 and No. 23. The ABS warning light illuminates.
B4M1228A

ABS-15
ABS (DIAGNOSTICS)
CONTROL MODULE I/O SIGNAL
*1: Measure the I/O signal voltage after removing the connector from the ABSCM&H/U terminal.
*2: Measure the I/O signal voltage at connector (B200) or (F74).
Contents Terminal No.
(+)—(−)Input/Output signal
Measured value and measuring conditions
ABS sensor*2
(Wheel speed sensor)
Front left wheel 9—10 0.12 —1 V
(When it is 20 Hz.)
Front right wheel 11—12
Rear left wheel 7—8
Rear right wheel 14—15
Valve relay power supply 24—23 10 —15 V
Motor relay power supply 25—23 10 —15 V
G sensor*2
(AWD model only)
power supply 30—28 4.75 —5.25 V
ground 28 —
output 6—28 2.3±0.2 V when vehicle is in horizontal position.
Stop light switch*1 2—23 Less than 1.5 V when the stop light is OFF and, 10 —15 V
when the stop light is ON.
ABS warning light*2 22—23 Less than 1.5 V during 1.5 seconds when ignition switch is ON,
and 10 —15 V after 1.5 seconds.
AT ABS signal*2
(AT model only) 31—23 Less than 1.5 V when the ABS control still operates and more than 5.5 V when ABS does not operate.
ABS operation signal monitor*2 3—23 Less than 1.5 V when the ABS control still operates and more
than 5.5 V when ABS does not operate.
Select monitor*2 Data is received. 20—23 Less than 1.5 V when no data is received.
Data is sent. 5—23 4.75 —5.25 V when no data is sent.
ABS diagnosis connec-
tor*2 Terminal No. 3 29—23 10 —15 V when ignition switch is ON.
Terminal No. 6 4—23 10 —15 V when ignition switch is ON.
Power supply*1 1—23 10 —15 V when ignition switch is ON.
Grounding line 23 —
Grounding line 26 —

ABS-16
ABS (DIAGNOSTICS) CONTROL MODULE I/O SIGNAL
B: SCHEMATIC
B4M2226
(1) ABS control module and hydraulic
control unit (ABSCM&H/U) (9) Front right outlet solenoid valve (17) ABS warning light
(10) Rear left inlet solenoid valve (18) Stop light switch
(2) ABS control module area (11) Rear left outlet solenoid valve (19) Stop light
(3) Valve relay (12) Rear right inlet solenoid valve (20) G sensor
(4) Motor relay (13) Rear right outlet solenoid valve (21) Front left ABS sensor
(5) Motor (14) Transmission control module (only
AT model) (22) Front right ABS sensor
(6) Front left inlet solenoid valve (23) Rear left ABS sensor
(7) Front left outlet solenoid valve (15) Diagnosis connector (24) Rear right ABS sensor
(8) Front right inlet solenoid valve (16) Data link connector

ABS-17
ABS (DIAGNOSTICS)
CONTROL MODULE I/O SIGNAL
C: WAVEFORM
B4M2526A

ABS-18
ABS (DIAGNOSTICS) SUBARU SELECT MONITOR
6. Subaru Select Monitor
A: OPERATION
1. READ DIAGNOSTIC TROUBLE CODE
1) Prepare Subaru Select Monitor kit.
2) Connect diagnosis cable to Subaru Select Mon-
itor.
3) Insert cartridge into Subaru Select Monitor.
<Ref. to ABS-10, SPECIAL TOOLS, PREPARA-
TION TOOL, General Description.>
4) Connect Subaru Select Monitor to data link con-
nector.
(1) Data link connector located in the lower por-
tion of the instrument panel (on the driver's
side).
(2) Connect diagnosis cable to data link con-
nector.
5) Turn ignition switch to ON (engine OFF) and
Subaru Select Monitor switch to ON.
6) On the «Main Menu»display screen, select the
{Each System Check} and press the [YES] key.
7) On the «System Selection Menu»display
screen, select the {Brake Control System} and
press the [YES] key.
8) Press the [YES] key after displayed the informa-
tion of engine type.
9) On the «ABS Diagnosis»display screen, select
the {Diagnostic Code(s) Display} and press the
[YES] key.
10) On the «Diagnostic Code(s) Display»display
screen, select the {Current Diagnostic Code(s)} or
{History Diagnostic Code(s)} and press the [YES]
key.
NOTE:
•For detailed operation procedure, refer to the
SUBARU SELECT MONITOR OPERATION MAN-
UAL.
•For detailed concerning diagnostic trouble
codes, refer to the LIST OF DIAGNOSTICS TROU-
BLE CODE. <Ref. to ABS-24, List of Diagnostics
Trouble Code.>
(1) Data link connector
S2M0285
S2M0286
(1)
BR0034
(1) Power switch
S2M0288D

ABS-19
ABS (DIAGNOSTICS)
SUBARU SELECT MONITOR
2. READ CURRENT DATA
1) On the «Main Menu»display screen, select the {Each System Check} and press the «YES»key.
2) On the «System Selection Menu»display screen, select the {Brake Control System} and press the «YES»
key.
3) Press the «YES»key after displayed the information of ABS type.
4) On the «Brake Control Diagnosis»display screen, select the {Current Data Display & Save} and press the
«YES»key.
5) On the «Data Display Menu»display screen, select the {Data Display} and press the «YES»key.
6) Using the scroll key, move the display screen up or down until the desired data is shown.
•A list of the support data is shown in the following table.
NOTE:
For detailed operation procedure, refer to the SUBARU SELECT MONITOR OPERATION MANUAL.
3. CLEAR MEMORY MODE
1) On the «Main Menu»display screen, select the {2. Each System Check} and press the «YES»key.
2) On the «System Select Menu»display screen, select {Brake System} and press the «YES»key.
3) Press the «YES»key after displayed the information of engine type.
4) On the «Brake Control Diagnosis»display screen, select the {Clear Memory} and press the «YES»key.
5) When the “Done”and “turn ignition switch OFF”are shown on the display screen, turn the Subaru Select
Monitor and ignition switch to OFF.
NOTE:
For detailed operation procedure, refer to the SUBARU SELECT MONITOR OPERATION MANUAL.
Display screen Contents to be monitored Unit of measure
FR Wheel Speed Wheel speed detected by the Front Right ABS sensor is displayed km/h or MPH
FL Wheel Speed Wheel speed detected by the Front Left ABS sensor is displayed km/h or MPH
RR Wheel Speed Wheel speed detected by the Rear Right ABS sensor is displayed km/h or MPH
RL Wheel Speed Wheel speed detected by the Rear Left ABS sensor is displayed km/h or MPH
Stop Light Switch Stop light switch signal ON or OFF
Stop Light Switch Stop light switch monitor voltage is displayed. V
G sensor output Signal Refers to vehicle acceleration detecting by the analog G sensor. It
appears on the select monitor display in volts. V
Valve Relay Signal Valve Relay Signal ON or OFF
Motor Relay Signal Motor Relay Signal ON or OFF
ABS Signal to TCM ABS operation signal from ABS control module to TCM ON or OFF
ABS Warning Lamp ON operation of the ABS warning light is displayed. ON or OFF
Motor Relay Monitor Operating condition of the motor relay is displayed. High or Low
Valve Relay Monitor Operating condition of the valve relay is displayed. ON or OFF
CCM Signal ABS operation signal from ABS control module to TCM ON or OFF