Master Cylinder/Brake Booster
Master Cylinder InspectionPushrod Clearance Adjustment
NOTE: Master cylinder pushrod'to piston clearance must
be checked and adjustments made, if necessary, before
installing master cylinder.
1. Set the special tool on the master cylinder body;
push in the center shaft until the top of it contacts the
end of the socondary piston by turning the adjusting
nut.PUS'IROD ADJUSTTTiENT GAUGE07JAG - SDiOl(xl
SECOITDARYPISTON
CEl{IERSHAFT
MASTER CYLINDER
Without disturbing the center shaft's position,
the soecial tool upside down on the booster.
3. Install the master cylinder nuts and tighten to the
sDecified toroue.
4. Connect the booster inline with a vacuum gauge 0 -
101 kPa {0 - 760 mmHg, 30 in.Hg) to the booster's
engine vacuum supply, and maintain an engine
speed that will deliver 66 kPa (500 mmHg, 20 in.Hg)
vacuum.
5. With a feeler gauge, measure the clearance between
the gauge body and the adjusting nut as shown.
Clsarance: 0 - 0,i[ mm (0 - 0.02 inl
VACUUM GAUGElCommelcially availabl€|0 - 101 kPal0 - 760 mm H9,30 in.Hgl
AINUSTING NUT
BRAKEBOOSTEB
MAS'ER CYLINDER NUT15 N.m ll.5 kgf.m. 11 lbl.ftl
CAUTION:
. Do not spill blake fluid on the vohicle; it may damago
th6 paint; if brake fluid does contast ths paint, wash
it off immsdiately with water.
. Before reassembling. chock that all parts are tree of
dust and othor toreign particlgs,
. Do not trv to dissssemblo the master cylinder
assembly. Replace the mast€r cylinder assembly
with s new part if nocossary.
. Make sure no dirt or othor toroign matter is allowed
to contaminate th€ brako fluid.
RESERVOIR SEALCheck for damage and
deterioration.
ROD SEALCheck for damageand deterioration.
AIIUSNNG NUT
19-14
FEELER GAUGE
1.
8.
NOTE: lf the clearance between the gauge body
and adjusting nut is 0.4 mm (0.02 in), the pushrod-
to-piston clearance is 0 mm. However, if the clear-
ance between the gauge body and adjusting nut is
0 mm, the pushrod-to-piston clearance is 0.4 mm(0.02 in) or more. Therefore it must be adjusted and
rechecked.
lf clearance is incorrect, loosen the star locknut and
turn the adjuster in or out to adjust.
NOTE:
. Adjust the clearance while the specified vacuum
is applied to the booster.
. Hold the clevis while adjusting.
Tighten the star Iocknut securely.
Remove the special tool.
0 - o.il mm l0 - 0.02 inl
Brake Booster Inspection
Functions Tgst
1. With the engine stopped, depress the brake pedal
several times to deplete the vacuum reservoir, then
depress the pedal hard and hold it for 15 seconds. ll
the pedal sinks, either the master cylinder is
bypassing internally; or the brake system (master
cylinder, lines, modulator proportioning valve, orcaliper) are leaking.
Start the engine with the pedal depressed. lf thepedal sinks slightly, the vacuum booster is operat-
ing normally. lf the pedal height does not vary, the
booster or check valve is faulty.
With the engine running, depress the brake pedal
lightly. Apply just enough pressure to hold back
automatic transmission creep, lf the brake pedal
sinks more than 25 mm (1.0 in.) in three minutes,
the master cylinder is faulty. A slight change inpedal height when the A,,/C compressor cycles on
and off is normal. (The A/C compressor load
changes the vacuum available to the booster.)
Leak Test
1. Depress the brake pedal with the engine running,
then stop the engine. lf the pedal height does not
vary while depressed for 30 seconds, the vacuum
booster is OK. lf the pedal rises, the booster is
fau lty.
2. With the engine stopped, depress the brake pedal
several times using normal pressure. When thepedal is first depressed, it should be low. On con-
secutive applications, the pedal height should grad-
ually rise. lf the pedal position does not vary, check
the booster check valve.
Boostor Ch€ck Valve T6st
1. Disconnect the brake booster vacuum hose at the
booster,
Start the engine and let it idle. There should be vac-
uum available. It no vacuum is available. the check
valve is not working properly. Replace the brake
booster vacuum hose and check valve, and retest.
VACUUM HOSE(Check valve built-in)
STAR LOCKNUT22 t{.m12.2 ksl.m, 16lbf.ftl
cLEVtS
ADJUSTER
ADJUSTMENT GAUGE07JAG - SD40t00
9. Adjust the pushrod length as shown if the booster
is removed.
1161 0.5 mm14.61 0.02 inl
PUSHRODLOCKNUT15 N m 11.5 kgf m, 11 lbf'ftl
10. Instali the master cylinder.
IABS Control
The ABS control unit detects the wheel speed based on the wheel sensor signal it received, then it calculates the vehiclespeed based on the detected wheel speed. The control unit detects the vehicle speed during deceleration based on therate of deceleration.
The ABS control unit calculates the slip rate of each wheel, and it transmits the control signal to the modulator unitsolenoid valve when the slip rate is high.
The pressure reduction control has three-modes: pressure reduction, pressure retaining, and pressure intensifying.
Self-diagnosis Function
The CPUS in the ABS control unit check the circuit of the system.
The self-diagnosis can be classifield into two categories.. Initial diagnosis: Performed right after the engine starts and until the ABS indicator gose off.. Regular diagnosis: Performed right after the initial diagnosis until the ignition switch isturnedoff.
On-board Diagnosis Function
The ABS control unit is connected to the data link connector fi6p).The ABS system can be diagnosed with the Honda PGM Tester.
(cont'd)
19-27
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Diagnostic Trouble Code (DTC)
DTG lndication
a
t
NOTE: This operation can also be done with the Honda PGM Tester.
1. Connect the SCS short connector to the service check connector (2P) under the glove box,
2. Turn the ignition switch ON (ll) without the brake pedal depressed.
NOTE: lf the brake pedal is depressed when turning the ignition switch ON (ll), the system shifts to the DTC Erasure
mode.
3. The blinking frequency indicates the DTC.
NOTE: lf the DTC is not memorized, the ABS indicator will go off fo r 3.6 seconds, and then come back on.
4. Turn the ignition switch OFF, and remove the SCS short connector.
NOTE: The Malfunction Indicator Lamp (MlL) will stay on after the engine is started if the SCS shon connector is con-
nected.
Conditions lor DTC indication
. Vehicle speed is 6 mph (10 km/h) or less.
. The SCS short connector is connected before the ignition switch is turned ON {ll).
. The brake pedal is released.
ABS INOICATOB
SCS SHORT CONNECTORo?PAZ - 0010100
SERVICE CHECKCONNECTOR I2PI
DTC : 3 3
b
Troubleshooting
ABS Indicator Does Not Go Off
JUMPERWIRE
ABS OO TNOL UMT 22P OO'{NECTOR
Wire side of temalo terminalg
A8S COI{TROL Ut{lT 12P OO I{ECTOR
JUMPEFWIRE
Wire side of femal€ terminala
|G2 IALK/YELI
- The ABS indicltor light doosnot go ofl aftor lhe engine is3tartod.- With the SCS sorvico connoctor connoct d l.oe page 19371,no DTC b indbat€d.
ChECK thE REAF DEFROSTERRELAY (7.5 A) fuse in the under-dash fuse/relay box, and reinstallthe fuso if it is OK.
Roplaco tho tusa and rocheck.
Chock for an opcn GND circuit:1. Connect the ABS control unit22P connector terminal No. 1to body ground with a jumper
2. Turn the ignition switch ON (ll).
. Ropair opon in tha wiro botwocntho ABS control unit and bodyground.' Ropair poo. ground {G701 }.
Check for an open in thc lG2 ci.-cuit:Measure the voltage botween theABS control unit 22P connectorterminal No. 11 and body ground.
Roprir opon in thc wira bdtwoentho REAR OEFROSTER RELAY17.5 Al fu$ end th. ABS controlunit.
ls th6re battery voltage?
Check the ABS contJol unit:Connect the ABS control unit 12Pconnector terminal No. 1 to bodyground with a jumper wire.
Chock for looao ABS control unhconncctoas, It nacas3aly, sub3ti-tuto a known-good ABS controlunit and r.check.
(To page 19-43)
19-42
- With the ignition switch ON(lll, the ABS indicator doesnot go off.- With the SCS s€.vice connec-tor connected lsee page 19-37), OTCS 11, 13, 15, 17 areindicated.
Check for a short to pow6r in thewheel sensor circuii:1. Disconnect the ABS controlu nit 22P connector.2. Start the engine.3, Measure the voltage betweenthe appropriate wheel sensor(+) circlit terminal and bodyground (see table).
Repair short to power in the {+)circuit wire between the ABScontrol unil and the approprialewheel sensor.
ls there 2 V or more?
Check for a short to body groundin th6 wheel sensor circuil:Check tor continuity between theappropriate wheel sensor (+) cir-cuit terminal and body ground(see table).. Ropair short lo body ground inthe {+) or {-l circuit wirebetween tho ABS contlol unitand th6 .ppropriate whe€l sen-
. Roplaco the .ppropliate wheelsensot.
ls there continuity?
Check for an open in the wheelsensor circuit:Check the resistance between theappropriate wheel sensor (+) and1-) circuit terminals (see table).
Ropair open in the {+) or (-} cir-cuit wire, or 3hort to the l+) cir-cuit wire in the l-l circuit wirebetween tho ABS control unitand th6 appropriate whgel 3en-
Replace th6 appropdate wh€elsensot.
ls the resistance OK?FronvRear: 450 - 2,050 O/20"c (68.F)
NOTE: lf you do not erase the DTC, the ABS indicator will not go off until vehicle speedexceeds 6 mph (10 km/h).
ABS CONTNOL UNIT 22P CONNECTOF
FLw {+l {GRN/ORN) FRw {+} (GRN/BLKI
oTcAppropriate Terminal
(+)Side( )side
11 (Right-front)No. 9: FRW (+)No. 8: FBW {-)
13 (Left'front)No.7: FLW (+)No.6: FLW 1-)
l5lBight-rear) iNo. 19:RRW (+!o. 20: RBW (-
17 (Left'r€af)17: RLW {+',1o. 18: RLW (-Wire side of lemale terminals
FLW (+) (GRN/ORN) FRW l+){GRN/BLK)
FLw l+l (GRN/ORNI FRW {-) {GRN}
FLW t-l(+l (GRN/BLKI
RL(-I {BLU/YELI
RLW l-) (GBY) RRW (+) (GRN/YEL)
Check for loose ABS control unitconnectors. lf necessary. substi-tute a known-good ABS controlunii and recheck.
RLW {+l (LT BLUI
RLw (+l {LT BLU}
-t(o
___r
l'!*
6l89l01t
1417t8t920
| ***-t
(()
Y
Troubleshooting
DTC 1 1, 13, 15, 17 : Wheel Sensor (open/short to body ground/short to power)
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9-44
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Troubleshooting
DTG 52: Motor Stuck OFF lcont'd)
PUMP ITIOTOR BELAY CONNECTOf,
JUMPERWIRE
Terminel side of female i€rminals
aBs oo tnol ut{tT 12P cof{f{EGToR
Wire side of lemale terminals
I
.t!
Ch.ck tor !n op.n in thc PMR cir-
cuit:1. Connoct tho pump motor relay
connector terminal No. 2 toNo.3 with a iumpor wir6.2, M€asure th6 voltage betw6entho A8S control unit 12P con-nector terminal No. 12 andbody ground.
R.p.ir op.n In th. wir. batw..nth. und.r-hood ABS tu../r.l.Ybox lnd th. ABS codrol unil.
Check lor a rho to pow.r in th.PMR circuii:1. Removo the jumper wire frompump motor relay connedor.2. Start the engine.3. ireasur6 the voltage betwoenth6 ABS control unit 12P con-nector terminal No. 12 8ndbody ground.
R.p.ir .hort to pow.r In th. wil.
brtwa!n lh. und..-hood ABSfur./r.l.y box rnd th. A8S con-trol unit.
ls th€re batt€ry voltage?
lf tha problam occura again,r.pllce th. ABS control unit.
Modulator Unit
Removal/lnstallation
CAUTION:
. Do not spill brake fluid on lhe vehicle; it may damage the paint; il brake fluid does contact the paint, wash it offimmediately with water.
. Tak€ care notto damage or delorm the brake lines during removal and installation.. To provont the brake fluid ftom flowing, plug and cover the hos€ ends and ioints with a shop towel or equiyalent material.
Removal
1. Disconnect the modulator unit and DUmD motor connectors.
2. Disconnect the brake lines, then remove the modulator unit.
Installation
1. lnstall the modulator unit, then connect the brake lines. Tighten the flare nuts to 15 N.m (1.5 kgf.m, 11 lbf.ft).2. Connect the modulator unit and pump motor connectors.
3. Bleed the brake system, starting with the front wheels.
4. Start the engine, and check that the ABS indicator goes off.
5. Test-drive the vehicle, and check that the ABS indicator does not come on.
From master cylinder
from master cylinderprimary side
PUMP MOTOB CONNECTOR
MOUNT
UNlT
MODULATOR UNIT CONNECTOR
toright front
8 mm EOLT22 N.m {2.2 kg[.m, 16 lbl.ftl
6 mm NUT9.8 N.m 11.0 ks{.m,7.2lbtftl
9-6