1991 MITSUBISHI 3000GT sensor

SERVICE BRAKES - Service Adjustment Procedures35-57
i
~18~17~16~15~14~13~12~11~10~ 9 18 I 7 16 I 5 14 13 12 1 1 1[35~34~33~32~31~30~29~28~27~26~25~24~23~22~21~20~19~Check connector
ECU
/m/Body harness
MB991 35614N018(
I I I 2When turned manually
~---~---~-.-~---[--.I 1MEASUREMENT OF
WHEEL SPEED SENSOR
OUTPUT VOLTAGEM35FOAO
1. Lift up the vehicle and release the parking brake.
2.Disconnect the ECU harness connector and measure with
the adapter harness (MB991 356) connected to the harness
side connector.
Caution
1. Never insert a probe, etc. into the connector as it
may result in poor contact later.
2.Do not connect the connector (Special Tool) markedwith “r+”except when recording the waveform on a
driving test. In such a case, connect the connector
to the ECU.
Terminal No. (same for AWD and FWD)
FL
RRFRRL
4
24218
52623393. Manually turning the wheel to be measured by
112 to 1
turn/second, measure the output voltage with a circuit
tester or oscilloscope.
Output voltage:
When measured with circuit tester: 70
mV or more
When measured with oscilloscope (max. voltage): 100
mV or more
Probable causes of low output voltage
l Speed sensor pole piece-to-rotor clearance too large
l Faulty speed sensor
4. Then, in order to observe the output state of the wheel
speed sensors, shift into low gear
(AWD vehicle) and drive
the wheels, observe the output voltage waveform of each
wheel speed sensor with an oscilloscope.
In the case of the FWD vehicle, observe the waveform with
an oscilloscope; for the front wheels, shift into low gear and
drive the wheels; for the rear wheels, turn the wheels
manually at a constant speed.
NOTE
1.Waveform may also be observed by actually driving the
vehicle.
2.The output voltage is low when the wheel speed is low
and increases as the wheel speed increases.
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35-58SERVICE BRAKES - Service Adjustment Procedures
POINTS IN WAVEFORM MEASUREMENT
Symptom
Too small or zero waveform
amplitudeProbable causes
Faulty wheel speed sensorRemedy
Replace sensor
Incorrect pole piece-to-rotor clearance
Adjust clearance
Waveform amplitude fluctuates
excessively (this is no problem ifAxle hub eccentric or with large runout
Replace hub
the minimum amplitude is
100 mV
or more)
Noisy or disturbed waveformOpen circuit in sensor
Open circuit in harness
Incorrectly mounted wheel speed sensor
Rotor with missing or damaged teethReplace sensor
Correct harness
Mount correctly
Replace rotor
NOTEThe wheel speed sensor cable moves following motion of the front or rear suspension. Therefore, it is likely that it has an
open circuit only when driving on rough roads and it functions normally on ordinary roads. It is, therefore, recommended
to observe sensor output voltage waveform also under special conditions, such as rough road driving,
(ME!991 377)12FOO5i
INSPECTION OF HYDRAULIC UNITINSPECTION BY FEEL
(I) Jack up the vehicle and support the vehicle with rigid racks
placed at the specified jack-up points.
(2) Release the parking brake and determine the drag force
(drag torque) of each wheel by feel.
LJ(3) Set the MUT through the adapter harness (MB991377) as
illustrated.
(4) After confirming that the shift lever or selector lever is in
the neutral position, start the engine.
The ABS warning light lights up, it goes into the MUT mode.
In the MUT mode, ABS does not function.
(5) Operate the MUT to force the actuator to operate (item No.
04, 05, 06).
(6) Turning the wheel manually, check the change of the
braking force when the brake pedal is depressed.
The change should be as shown in the following illustration.
NOTEWhile the ABS is in the fail safe mode, the MUT actuator
test cannot be made.
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Brake tube flare nut15Nm
11 ft.lbs.
m14FO38

Post-installation Operationl Supplying Brake Fluid
l-----l
l Bleeding(Refer to P.35-48.)l Adjustment of Brake Pedal
(Refer to P.35-45.)

81
‘414ux216 1
Sealant: 3M ATDPart No.
-----I8663 or equivalent
SERVICE BRAKES - Master Cylinder and Brake Booster35-67
MASTER CYLINDER AND BRAKE BOOSTER
L
REMOVAL AND INSTALLATION
14 NmIO ft.lbs.
10 Nm
7 ft.lbs.
Master cylinder removal steps
*I)1. Low-pressure hose
2. Brake fluid level sensor connector
3: Brake tube connection
4. Master cylinder
l e .Adjustment of clearance between brake
booster push rod and primary piston
Brake booster removal steps
4.Master cylinder5.Vacuum hose6.Vacuum tubel a7. Vacuum hose with check valve8.Fitting9.Cotter pin10.Washer11.Clevis pin.
12.Sealer13.Spacer
14.Brake booster
lb14FOlll
9 10
bpr.
m
cl11
1 t
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SERVICE BRAKES - Master Cylinder and Brake Booster35-69light
scale14AO471
DISASSEMBLY AND REASSEMBLY
Brake fluid: Conforming to DOT3
Disassembly steps
1. Reservoir cap assembly
2. Diaphragm
3. Reservoir cap4. Filter
5. Brake fluid level sensor
6. Float7. Reservoir stopper bolt
8. Reservoir
9. Reservoir seal
*I)IO. Piston stopper bolt
11. Gasket
a*12. Piston stopper ring
13. Primary piston assembly
a*14. Secondary piston assembly
15. Master cylinder body(3) Measure the dimension
(D)der mounting surface on brake booster and the push
rod end.
NOTETo obtain
(D), first take measurement with a square
placed on the brake booster. Then, subtract the thick-
(D).
(3),push rod and primary piston.
Standard value: A (A
=- C - D)
7
+ 8 inch brake booster
0.55
- 0.75 mm (.022 - .030 in.)
8
+ 9 inch brake booster
0.65
- 0.85 mm (.026 - .033 in.)
(5) If the clearance is not within the standard value range,
adjust by changing the push rod length by turning the
adjustable end of the push rod.
Caution
Improper clearance may cause excessive brake
drag.M35HA-
-
14FOll3
Do not disassemble the primary ancH secondary
piston assembly.
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3588SERVICE BRAKES - Wheel Speed Sensor (ABS)WHEEL SPEED SENSOR (ABS)
REMOVAL AND INSTALLATION

a*1. Front rotorFront speed sensor removal steps
2. Clip*I) ++ 3. Front speed sensorw 4. Front speed sensor bracket*I)5. Rear rotorRear speed sensor removal steps
6. Clipa* l + 8. Rearspeedsensor
M350A-B L/ 1
(Refer to Group 42 - Fender.)
14FOO78LJ
Post-installation Operationl Installation of Splash Shield (Front Only)(Refer to Group 42 - Fender.)l Inspection of A.B.S.(Refer to P.35-7.)TSB Revision

L
SERVICE BRAKES - Wheel Speed Sensor (ABS)35-89

12 Nm9 ft.lbs.
6
2
3
12 Nm- 9 ft.lbs.
a*I, Front rotor
Front speed sensor removal steps
2. Clipl * I)*3. Front speed sensora*5. Rear rotorRear speed sensor removal steps
6. Clip
7. Cable band
+I) l *8. Rear speed sensor9. O-ringPre-removal Operation
lRemoval of Splash Shield (Front Only)(Refer to Group 42 - Fender.)1
Post-installation Operationl Installation of Splash Shield (Front Only)(Refer to Group 42 - Fender.)l Inspection of A.B.S.
(Refer to P.35-7.)14FOlOO
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SERVICE BRAKES - Wheel Speed Sensor (ABS)
IFrontRear

+ : Pole piece14N016:14NOlO:
SERVICE POINTS OF REMOVALM35OBAC
1.REMOVAL OF FRONT ROTOR / 5. REMOVAL OF REAR
ROTOR
CautiondDo not damage rotor teeth and never drop the rotor.
If the rotor has missing teeth or is deformed, accuratewheel speed detection cannot be expected and the
system may fail to function normally.
Use particular care in handling the front rotor of an
AWD vehicle as it cannot be disassembled.
3.REMOVAL OF FRONT SPEED SENSOR / 8. REAR SPEED
SENSOR
Caution
When removing the speed sensor from the knuckle, usecare not to strike the tip of the pole piece against the
rotor teeth or any other parts.
INSPECTIONMJSOCAC
INSPECTION OF SPEED SENSOR(1) Check the tip of the speed sensor pole piece for deposits of
metal or other foreign matter and clean the pole piece as
necessary.
Also check the pole piece for damage and replace if
damaged.d
Caution
The speed sensor pole piece is magnetized by a built-in
magnet inside the sensor, so it tends to attract metal.If the pole piece is damaged, accurate wheel speed
detection may not be expected.
(2) Measure resistance between speed sensor terminals.
Standard value:
Front
Rear
1.4-2.2
kR1.3-2.1
kR
0.8- 1.2 kfl
If the internal resistance of the speed sensor is out of
specification, replace with a new one.

SERVICE BRAKES - Wheel SDeed Sensor lABSI35-91
/
i
lARnlA6
14N012‘
3
(3) zue$ the speed sensor cable for open circuit and replace if
NOTERemove the cable clamp from the body and, while flexing
the cable near the clamp, check for temporary open circuit.
Also check connector connection and terminal insertion.
INSPECTION OF ROTORCheck the rotor for missing or worn teeth and replace if faulty.
SERVICE POINTS OF INSTALLATIONM350DAC8. INSTALLATION OF REAR SPEED SENSOR
Insert a feeler gauge between the speed sensor pole piece
and the rotor tooth surface and tighten the speed sensor to
specified torque where the clearance is as specified all
around.Standard value: 0.2
- 0.7 mm (.008 - .028 in.)
NOTEThe rear speed sensor pole piece-to-rotor tooth surface
clearance is not adjustable in the case of AWD vehicles. In
this case, measure the sensor mounting surface-to-rotor
tooth surface clearance.
Standard value: 28.15
- 28.45 mm (1.11 - 1.12 in.)
4. INSTALLATION OF FRONT SPEED SENSOR BRACKET
NOTE
(I) The right and left speed sensor brackets differ in shape.
Install correctly referring to the identification symbols.
FR: For front speed sensor
R:For right wheel
L:For left wheel
(2) After installation of the speed sensor to the bracket,
check that the letters “FR” are visible.
3. INSTALLATION OF FRONT SPEED SENSOR
Caution
Handle the speed sensor carefully so as not to strike the
tip of the pole piece or the rotor teeth against any metalparts and damage them.
Insert a feeler gauge between the speed sensor pole piece
and rotor tooth surface and tighten the speed sensor to
specified torque where the clearance is as specified all
around.Standard value: 0.3
- 0.9 mm (.012 - .035 in.)
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