brake sensor SUBARU LEGACY 1995 Service Manual Online

M: TROUBLE CODE 58
—FAULTY PRESSURE SWITCH—
DIAGNOSIS:

Faulty pressure switch

Faulty stop light switch

Faulty harness/connector

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

TCS does not operate.
1. Check contact point of pressure switch.
OK
Not OK
Replace hydraulic unit.
2. Check body short of pressure switch.
OK
Not OK
Replace hydraulic unit.
3. Check harness between pressure switch and
ABS/TCS control module.
OK
Not OK
Repair harness/connector.
4. Check body short of pressure switch harness.
OK
Not OK
Repair harness.
5. Check contact point of stop light switch.
OK
Not OK
Replace stroke sensor.
6. Check body short of stop light switch.
OK
Not OK
Replace stroke sensor.
7. Check power supply of stop light switch.
OK
Not OK
Repair harness.
8. Check input voltage of ABS/TCS control mod-
ule.
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.








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8. Diagnostics Chart with Trouble Code

B4M0735A
2. CHECK BODY SHORT OF PRESSURE SWITCH.
1) Turn ignition switch OFF.
2) Disconnect hydraulic unit connector.
3) Measure resistance between hydraulic unit connector
and body.
Connector & terminal / Specified resistance:
(F12) No. 1—body/1MΩor more
(F12) No. 2—body/1MΩor more
B4M0477A
3. CHECK HARNESS BETWEEN PRESSURE SWITCH
AND ABS/TCS CONTROL MODULE.
1) Turn ignition switch OFF.
2) Connect hydraulic unit connector.
3) Disconnect ABS/TCS control module connector.
4) Measure resistance between ABS/TCS control module
connector terminals.
Connector & terminal / Specified resistance:
(P7) No. 6—No.18/1MΩor more (With brake
pedal
depressed)
(P7) No. 6—No. 18 / 1Ωor less (Without brake
pedal depressed)
B4M0478A
4. CHECK BODY SHORT OF PRESSURE SWITCH
HARNESS.
1) Turn ignition switch OFF.
2) Disconnect ABS/TCS control module connector.
3) Measure resistance between ABS/TCS control module
connector and body.
Connector & terminal / Specified resistance:
(P7) No. 6—body/1MΩor more
(P7) No. 18—body/1MΩor more
B4M0466A
5. CHECK CONTACT POINT OF STOP LIGHT
SWITCH.
1) Turn ignition switch OFF.
2) Disconnect stop light switch connectors.
3) Remove stroke sensor.
4) Measure resistance between stroke sensor terminals.
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8. Diagnostics Chart with Trouble Code

Terminal:
No. 2—No. 3
Stroke
Unit: mm (in)Specified
resistance
0—2.2±1.0 (0—0.087±0.039) 1 MΩor more
2.2±1.0—18.0±0.5 (0.087±0.039—0.709±0.020) 1Ωor less
NOTE:
Stroke = 0 when the rod is completely drawn in.
B4M0467A
6. CHECK BODY SHORT OF STOP LIGHT SWITCH.
1) Turn ignition switch OFF.
2) Disconnect stroke sensor connectors.
3) Remove stroke sensor.
4) Measure resistance between stroke sensor terminal
and stroke sensor threads.
Terminal / Specified resistance:
No. 2—stroke sensor threads/1MΩor more
No. 3—stroke sensor threads/1MΩor more
B4M0468A
7. CHECK POWER SUPPLY OF STOP LIGHT
SWITCH.
1) Turn ignition switch OFF.
2) Disconnect stroke sensor connector.
3) Measure voltage between stroke sensor connector and
body.
Connector & terminal / Specified voltage:
(B67) No. 3—body / 10—13 V
B4M0469A
8. CHECK INPUT VOLTAGE OF ABS/TCS CONTROL
MODULE.
1) Turn ignition switch OFF.
2) Install stroke sensor.
3) Connect stroke sensor connector.
4) Disconnect ABS/TCS control module connector.
5) Measure voltage between ABS/TCS control module
connector and body.
Connector & terminal / Specified voltage:
(P7) No. 7—body / 10—13 V (With brake pedal
depressed)
(P7) No. 7—body/0V(Without brake pedal
depressed)
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8. Diagnostics Chart with Trouble Code

G2M0096
9. Select Monitor Function Mode
Applicable cartridge of select monitor: No. 498349601
A: LIST OF FUNCTION MODE
1. F MODE (ROM ID, ANALOG DATA ARE
DISPLAYED.)
Function code
Measuring
itemsContents to be monitored Scroll Ref. to 4-4b
Code Abbreviation
F00 ROMECM identifi-
cationROM ID number of ECM is read and enabled com-
munication state is displayed.Possible [T9B0]
F01 FRFR wheel
speed (mile/h)Wheel speed detected by the FR wheel speed sen-
sor is displayed in mile/h.Possible [T9C0]
F02 FLFL wheel
speed (mile/h)Wheel speed detected by the FL wheel speed sen-
sor is displayed in mile/h.Possible [T9D0]
F03 RRRR wheel
speed (mile/h)Wheel speed detected by the RR wheel speed sen-
sor is displayed in mile/h.Possible [T9E0]
F04 RLRL wheel
speed (mile/h)Wheel speed detected by the RL wheel speed sen-
sor is displayed in mile/h.Possible [T9F0]
F05 FRFR wheel
speed (km/h)Wheel speed detected by the FR wheel speed sen-
sor is displayed in km/h.Possible [T9C0]
F06 FLFL wheel
speed (km/h)Wheel speed detected by the FL wheel speed sen-
sor is displayed in km/h.Possible [T9D0]
F07 RRRR wheel
speed (km/h)Wheel speed detected by the RR wheel speed sen-
sor is displayed in km/h.Possible [T9E0]
F08 RLRL wheel
speed (km/h)Wheel speed detected by the RL wheel speed sen-
sor is displayed in km/h.Possible [T9F0]
F09 PSSPedal stroke
sensor outputThe number of output steps of the pedal stroke
sensor is displayed.Possible[T9G0]
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9. Select Monitor Function Mode

2. FA MODE (ON/OFF DATA ARE DISPLAYED.)
If the system is in normal condition with the engine run at
idle speed (when the brake pedal is off), the LED of EC
(AEC signal) of FA2 will come on, the LED of EM (EAM
signal) blink and all other LED’s go out.
Function code
Measuring
itemsContents to be monitored Scroll Ref. to 4-4b
Code Abbreviation
FA 0OF OFF.SW LED 1 comes on with the OFF switch on.
Possible [T9H0] B1Stop light
switchLED 2 comes on with the switch on (with the brake
pedal down).
VRValve relay
signalLED 3 comes on with the valve relay off.
VMValve relay
monitorLED 4 comes on with the valve relay off.
MRMotor relay
signalLED 5 comes on with the motor on.
MS Motor sensor LED 6 comes on with the motor on.
FSFluid level
sensorLED 7 comes on with the sensor on (the fluid level
is lowered).
FA 1FI FR.IN valveLED 1 comes on when the FR.IN valve is operat-
ing.
Possible [T9I0] RO FR.OUT valveLED 2 comes on when the FR.OUT valve is operat-
ing.
FL FL.IN valve LED 3 comes on when the FL.IN valve is operating.
LO FL.OUT valveLED 4 comes on when the FL.OUT valve is operat-
ing.
T1 TCS1 valve LED 5 comes on when the TCS1 valve is operating.
RI RR.IN valveLED 6 comes on when the RR.IN valve is operat-
ing.
RO RR.OUT valveLED 7 comes on when the RR.OUT valve is operat-
ing.
RI RL.IN valve LED 8 comes on when the RL.IN valve is operating.
LO RL.OUT valveLED 9 comes on when the RL.OUT valve is operat-
ing.
T2 TCS2 valveLED 10 comes on when the TCS2 valve is operat-
ing.
FA 2AWABS warning
lightLED 1 comes on when the warning light is on.
Possible [T9J0] TWTCS warning
lightLED 2 comes on when the warning light is on.
TOTCS OFF
indicator lightLED 3 comes on when the indicator light is on.
TITCS operation
indicator lightLED 4 comes on when the indicator light is on.
EC AEC signalWith the engine run at idle speed, LED 6 (AEC)
comes on and LED 7 (AEB) goes out (They go on
and off depending on the behavior of a vehicle.) EB AEB signal
ET AET signal LED 8 comes on with the TCS control on.
EM EAM signalLED 9 comes on or blinks when the engine control
is enabled.
AT AAT signal LED 10 comes on when ABS control is on.
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9. Select Monitor Function Mode

B4M0483
F: MODE F04 AND F08
—REAR LEFT WHEEL SPEED SIGNAL (RL)
—

Compare speedometer with monitor indications.

F04: RL wheel speed is indicated in mile per hour (mile/
h).

F08: RL wheel speed is indicated in kilometer per hour
(km/h).
NOTE:
The monitor as shown, indicates that RL wheel speed is 50
mile/h.
B4M0484
G: MODE F09
—PEDAL STROKE SENSOR SIGNAL (PSS)
—

Indicates the output step number of the pedal stroke
sensor.
LED No. Signal name Display
1 TCS OFF switch OF
2 Stop light switch B1
3 Valve relay signal VR
4 Valve relay monitor VM
5 Motor relay signal MR
6 Motor sensor MS
7 Brake fluid level sensor FS
8——
9——
10——
OF B1 VR VM MR
MS FS———
1
2345
678910
H: MODE FA0
—ON↔OFF SIGNAL—
Requirement for LED“ON”
LED No. 1 T.C.S OFF switch is turned ON.
LED No. 2 Stop light switch is turned ON. (With brake
pedal depressed.)
LED No. 3 Valve relay is turned OFF.
LED No. 4 Valve relay is turned OFF.
LED No. 5 Motor relay is turned ON.
LED No. 6 Motor is rotating.
LED No. 7 Brake fluid level sensor is turned ON. (Brake
fluid is insufficient.)
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9. Select Monitor Function Mode

B: LIST OF TROUBLE CODE
Diagnostic items
(select monitor FB0)CodeDisplay screen
(FB0)Diagnostic items (select monitor FB1) Display screen (FB1)Ref. to
4-4b
Normal 11 NO TROUBLE Normal NO TROUBLE [T10C0]
Detection of FR sensor
hardware21 FR.SS HARDOpen circuit of FR sensor FR.SS OPEN [T10D1]
Short circuit of FR sensor FR.SS SHORT [T10D2]
Detection of FR sensor
software22 FR.SS SOFTFR sensor, variations in wheel speed FR.SS W.SPEED [T10E1]
FR sensor, reduced pressure mode FR.SS OR MV [T10E2]
FR sensor, wheel speed higher than prescribed FR.SS OVER [T10E3]
Detection of FL sensor
hardware23 FL.SS HARDOpen circuit of FL sensor FL.SS OPEN [T10F1]
Short circuit of FL sensor FL.SS SHORT [T10F2]
Detection of FL sensor
software24 FL.SS SOFTFL sensor, variations in wheel speed FL.SS W.SPEED [T10G1]
FL sensor, reduced pressure mode FL.SS OR MV [T10G2]
FL sensor, wheel speed higher than prescribed FL.SS OVER [T10G3]
Detection of RR sensor
hardware25 RR.SS HARDOpen circuit of RR sensor RR.SS OPEN [T10H1]
Short circuit of RR sensor RR.SS SHORT [T10H2]
Detection of RR sensor
software26 RR.SS SOFTRR sensor, variations in wheel speed RR.SS W.SPEED [T10I1]
RR sensor, reduced pressure mode RR.SS OR MV [T10I2]
RR sensor, wheel speed higher than prescribed RR.SS OVER [T10I3]
Detection of RL sensor
hardware27 RL.SS HARDOpen circuit of RL sensor RL.SS OPEN [T10J1]
Short circuit of RL sensor RL.SS SHORT [T10J2]
Detection of RL sensor
software28 RL.SS SOFTRL sensor, variations in wheel speed RL.SS W.SPEED [T10K1]
RL sensor, reduced pressure mode RL.SS OR MV [T10K2]
RL sensor, wheel speed higher than prescribed RL.SS OVER [T10K3]
Abnormal FR.IN valve 31 FR.IN VALVE Abnormal FR.IN valve FR.IN VALVE [T10L0]
Abnormal FR.OUT
valve32 FR.OUT VALVE Abnormal FR.OUT valve FR.OUT VALVE [T10M0]
Abnormal FL.IN valve 33 FL.IN VALVE Abnormal FL.IN valve FL.IN VALVE [T10N0]
Abnormal FL.OUT
valve34 FL.OUT VALVE Abnormal FL.OUT valve FL.OUT VALVE [T10O0]
Abnormal RR.IN valve 35 RR.IN VALVE Abnormal RR.IN valve RR.IN VALVE [T10P0]
Abnormal RR.OUT
valve36 RR.OUT VALVE Abnormal RR.OUT valve RR.OUT VALVE [T10Q0]
Abnormal RL.IN valve 37 RL.IN VALVE Abnormal RL.IN valve RL.IN VALVE [T10R0]
Abnormal RL.OUT
valve38 RL.OUT VALVE Abnormal RL.OUT valve RL.OUT VALVE [T10S0]
Abnormal ECM 41 ECU Abnormal ECM ECU [T10T0]
Abnormal line voltage 42 HIGH VOLTAGE Abnormal line voltage HIGH VOLTAGE [T10U0]
Abnormal EGI commu-
nication line43 EGI LINE Abnormal EGI communication line EGI LINE [T10V0]
Abnormal valve relay 51 V.RELAYValve relay ON failure V.RELAY ON [T10W1]
Valve relay OFF failure V.RELAY OFF [T10W2]
Abnormal motor sys-
tem52 MOTORMotor relay ON failure MOTOR ON [T10X1]
Motor relay OFF failure MOTOR OFF [T10X2]
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10. Diagnostic Chart with Select Monitor

Diagnostic items
(select monitor FB0)CodeDisplay screen
(FB0)Diagnostic items (select monitor FB1) Display screen (FB1)Ref. to
4-4b
Abnormal stroke sen-
sor and stop light
switch54 PSS & BLSOpen/short circuits of stroke sensor B.SW HARD [T10Y1]
Comparison of stroke sensor and acceleration B.SW SOFT(G) [T10Y2]
Comparison of stroke sensor and stop light switch B.SW SOFT(B) [T10Y3]
Comparison of stroke sensor and pump B.SW SOFT(P) [T10Y4]
Open circuit of stop light switch B.SW SOFT(O) [T10Y5]
Abnormal fluid level
sensor line57 FLUID LEVEL SS Abnormal fluid level sensor line FLUID LEVEL SS [T10Z0]
Abnormal pressure
switch58 PRESSURE SW Abnormal pressure switch PRESSURE SW [T10AA0]
Abnormal TCS1 valve 61 TCS1 VALVE Abnormal TCS1 valve TCS1 VALVE [T10AB0]
Abnormal TCS2 valve 62 TCS2 VALVE Abnormal TCS2 valve TCS2 VALVE [T10AC0]
1. IF THE SELECT MONITOR IS USED FOR
TROUBLESHOOTING, IT IS ADVISED TO FOLLOW
THE PROCEDURE BELOW
1) Activate function FB0 to read the most recent trouble
code and record it.
2) Activate function FB1 to read all trouble codes and
record them.
(If troubles occur in the wheel speed sensor, stop & brake
switch, valve relay or motor system, detailed data on
troubles are displayed by the FB1 function, allowing you to
easily locate points where need repair.)
3) Perform troubleshooting mainly in the FB1 mode.
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10. Diagnostic Chart with Select Monitor

B4M0490
C: TROUBLE CODE 11
—NO TROUBLE—
DIAGNOSIS:

ABS/TCS control module does not store troubles.
B4M0491
D: TROUBLE CODE 21
1. FR.SS OPEN
—Faulty front right ABS sensor (Open circuit)—
DIAGNOSIS:

Faulty ABS sensor

Faulty harness and connector

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.
1. Check resistance of ABS sensor.

OK
Not OK
Replace ABS sensor.
2. Check harness connector between ABS/TCS
control module and ABS sensor.

OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.
NOTE:
When checking ABS sensor, carefully bend or swing con-
nector and harness to check for improper contacts or open
circuits.


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10. Diagnostic Chart with Select Monitor

B4M0492
2. FR.SS SHORT
—Faulty front right ABS sensor (Short circuit)—
DIAGNOSIS:

Faulty ABS sensor

Faulty harness and connector

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS and TCS do not operate.

TCS does not operate.
1. Check resistance of ABS sensor.

OK
Not OK
Replace ABS sensor.
2. Check body short of ABS sensor.

OK
Not OK
Replace ABS sensor.
3. Check body short of harness.

OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.
NOTE:
When checking ABS sensor, carefully bend or swing con-
nector and harness to check for improper contacts or open
circuits.



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10. Diagnostic Chart with Select Monitor