L-
t
Anti-lock Brake System (ABSI
Special Tools ............. 19-44
Component Locations ......................... 19-45
Anti-lock Brake System (ABS)
Features/Construction ..................., 19-46
Operation ............... 19-47
Circuit Diagram ......... 19-50
ABS Control Unit Terminal
Arrangement ......... 19-52
Troubleshooting Precautions ............. 19-54
Diagnostic Trouble Code (DTCI
Diagnostic Trouble Gode (DTCI
Indication ........... 19-56
DTC Erasure ........... 19-57
Symptom-to System Chart ............. 19-58
Troubleshooting
ABS Indicator Light Does Not
Come On ............ 19-60
ABS Indicator Light Does Not
Go Off ............................................ 19-62
Wheel Sensor ........ 19-64
Solenoid ................. 19-60
ABS Pump Motor ............................. 19-68
Main Relay ............. 19-71
lgnition Voltage .... 19-73
Central Processing Unit {CPU} ........ 19-74
Modulator Unit
Removal/lnstallation ....................... 19-75
ABS Control Unit
Replacement ......... 19-76
Pulsers/Wheel Sensors
Inspection .............. 19-76
Wheel Sensor Replacement ............ 19-77
t/
e\
t
ABS CONTROL UNIT 22P CONNECTOR
Wire side of female terminals
TerminalnumbelWirocororTerminalsignDe3cription
Volt.ge
ConditionE(lgnition Switch ON (ll)lOutput voltagolTqrminal namslterminils
RED/BLUFR-IN{Front-rightinlet)
Drives right-front inletsolenoid valve.
I-GNDriJ
ON-9ONOV
OFFAC: 3-6 V
OFF
/Connect the SCS servicq
connector IApprox. 3 V
BRNscs(Service checksignal)
Detects service check signal
{Diagnostic trouble codeindication)4-GND
SCS service connectorconnected.OV
SCS service connectordisconneded.Appro)(. 5 V
7BLU/RED(Warning
ramp)
Drives ABS indicator light (The
indicator light go€s off when
ABS control unit outputs bat-
tery volta9e),
7-GND
Indicator light ONApprox, 2 V
Indicator light OFFBattery voltage
8BLU/YELNot used.
10YEUBLKFL.OUT{Front-leftoutlet)
Drives left-front outletsolenoid valve.10-GNOON
ONOV
OFFAC:3-6 V
11RED/BLKFLIN{Front-l€ft inlet)
Drives left-front inlet solenoid11-GNDOFF
lconnect the SCS servicq
connector IApprox. 3 V
YEUBLU
FR.OUT(Front-right
outlet)
Drives right-front outlet
solenoid valve.12-GNO
l4LT BLUDLC(Data linkconnector)
Communicates withPGM Tester.Honda14.GNDApprox. 5 V
17BRNA/ELMCK
lMotor check)
Detects pump motor drivesrgnal.17.GNDPumpmotorreray
ONBattery voltage
OFFOV
19YELREDPMR(Pump motorreray,
Drives pump motor relay.
19-GND
ONONOV
OFFAC: 3-6 V
OFFponnect the SCS sewicq
connedor lApprox. 3 V
BLURR-OUT(Rear-right
outletl
Drives right-rear outlel
solenoid valve.
21-GNDuJ
ON
Pumpmotorrelay
ONOV
OFFAC: 3-6 V
OFF
lconnect the SCS servicq
connedor )Approx. 3 V
22BLKGND2(Ground 2)Ground for the ABS controluntt.22-GNDBelow 0.3 v
19-53
Troubleshooting Precautions
ABS Indicator Light
I The ABS indicator light comes on when the ABS control unit detects a problem in the system. However, even thoughthe system is normal, the ABs indicator light can come on, too, under the following conditions. To determine theactual cause of the problem, question the customer about the problem, taking the following conditions into consider-ation.
. Signal disturbance
. Wheel soin
. Only drive wheels rotate. Battery voltage fluctuates
2. When a problem is detected and the ABS indicator light comes on, the indicator light can stay on untat the ignitionswitch is turned off, or it can automatically go off, depending on the mode.. Lightstayson until the ignition switch isturned off;When the system is inthesvstem down mode.o Light automatically goes off:When the system is in the control inhibition mode.(refer to symptom-to-system chart)3 The ABS indicator light stays on when the system is reactivated without erasing the DTC, but it goes off after startingthe car.
when the wheel sensor system is faulty and the ABS indicator light comes on, the algorithm of the system automaticallyturns off the ABS indicator light after the wheel speed signal returns to the normal speed. while, when the DTC is erased,the CPU is reset and the ABS indicator light goes off when the system check€d out normal by the initial diagnosis.Therefore, test-drive the car after servicing the wheel sensor system, and be sure that the ABS indicator light does notcome on.
4. When the ABS control unit outputs battery voltage to the gauge assembty, the ABS indicator light goes off.
Diagnostic Trouble Code (DTC)
1. The diagnostic trouble code (DTC) is memorized when a problem is detected and the ABS indicator light does not gooff, or when the ABS indicator light comes on.The DTC is not memorized when the ABs indicator right comes on unress the cpU is activated.2. The memory can hold any number of DTCs. However, when the same DTc is detected twice or more, the later one iswritten over the old one.
Therefore. when the same problem is detected repeatedly, it is recorded as one DTC.3. The DTCS are indicated in the order of ascending number, not in the order thev occur.4. The DTCS are memorized in the EEpROM {non-volatile memorv}.Therefore, the memorized DTCS cannot be canceled by disconnecting the battery. perform the specified orocedures toerase.
Solf-diagnosis
1. The self-diagnosis can be classifield into these four categories:' Initial diagnosis; Performed right after the engine sta rts and untiltheABs indicator light goes off.o Except ABS control: Performed when the ABS is not functioning,. During ABS control: Performed when the ABS is functioning.. During warning: Performed when the ABS indicator light is ON.2 The system performs the following controls when a problem is detected by the self-diagnosis:. ABS indicator light ON. Memory of DTC
. Mode change to the "system down mode,, or the "control inhibition mode,,.
MODEABS INDICATOR LIGHTMAIN
RELAY
SOLENOID
VALVECPURestart conditionDTC
SYSTEM
DOWNONNo
operal|on
Drive
inhibitionOperation+rlgnition
switchOFF - ONMemory
CONTROL
INHIBITIONONNo
operat|on
Orive
inhibitionOperationAutomaticMemory
*1: Except CPU failure
19-54
Diagnostic Trouble Code (DTCI
Diagnostic Trouble Code {DTC) Indication
NOTE: This operation can also be carried out with the Honda pGM Tesrer.
l connect the scs service connector to the service check connector inside the passenger,s side kick panel.
2. Turn the ignition switch ON (||). but do not start the engine.NOTE: Do not depress the brake pedal when turning the ignition switch.
3 Record the brinking frequency of the ABS indicator right. The brinking frequency indicates the DTc.
4, Turn the ignition switch OFF, and remove the SCS service connector.NorE: The Mslfunction Indicator Lamp (MlL) will stay on after the engine is started if the scs service connector isconnected.
5. Erase the DTC.
Condhions for DTC indication. The vehicle is stoDDed.. The SCS service connector is connected before the ignition switch is turned ON fll).. The brake pedal is released.. Th€ SCS service connector remains connected during this procedure
The DTG indication stops 8nd the ABs conltol unit executes the softwaro tunqtion if at least one of the following condi-tions b satisfied:
o The vehicle is not stoDoed.' The ABS control unit receives the normat signal (which is for the ABS controt unit) from a Honda pGM Tester.. The SCS service connector is disconnected during this procedu.e,
u.s.A.
@
CANADA
@
SERVICE CHECKCONNECTOR {2PISCS SERVICE CONNECTOR07PAZ - 0010100
ABS INDICATOR LIGHT
DTC : 3 3
A8S INDICAIOR LIGHT
Snilion swirch
' when the ignition switch is turned oN (ll), the ABs indicator light comes on to check the bulb. Do not count it as a DTc.o The ABS control unit can memorize any number of DTCs.. The new DTC is not memorized when the ABS control unit has already memorized the same DTC,.lftheDTCisnotmemorized,theABSindicatorlightstaysONafteritgoesofffor3.6seconds.
19-56
Diagnostic Trouble Code (DTCI
Symptom-to-System Chart
DTC
oH1=DIAGNOSIS/SYMPTOM
DETECTION TIMING
>=PNOBABLE CAUSEi.'sEV98€E
zr\9=6<_6
=t
6tz
NODTC
ABS indicator iighr doesnot com€ on when ignirionswrt.h is lu.ned on (ll)
, Open in the pow€. source circ!ir ror the ABS -.ndicato;l isht. Elown ABS indicalo.lighr butb' Open in rhe ABS indicaror tight drive cncuit.. Shori ro pow€r in theWALpcircuit. FaultyABS contrct!nit
ONABS indicator light doesnol90 oft 6frer engine isOpen in the lG2 circuitOpon in the +B circuirOp€n andlor short ro body ground jn the WALP circuitFaultv AAS coni.ol unnt1
oN.Wheel sensor (op€n/shortOooo13upen, snofiro bodyground and/or shodro power in rhe wh€61
Faulty ABS co.lrctunitllBL12
oN.(chipp€d pulser gea/noise)oao
Short to wh6sls€n6or (O)circuir in t'e.h;;Go-nso, trtcircutiFaulty whsel s€nsor insra|ation
Faulty ABS cont.olunir
I8
31
ONSolenoid (open/shon roaoa
Op.ni shon to bodyground and/o. shorrto powsr in rhe
op€n in lh6 coM circuit
Faulty ABS conlrclunit
32F8-OUTFL.IN3'lFT.OUTRF.IN88 OUT318t rN38RLOUT
ONoo
op€n in tho motor pow€..ourco circliaOp€n inih€ moro.cNOcircuit
Faulty ABS conrrol unit
52ONoo
Open in rh€ COM, PMR 6nd/o. MCKcircuirOp€n.n.Vor blown lus€ in the under hood AgS rusdretry box
Faufty pump moto. rotayfaulv ABS conlrolunit
53ONo
. Sho.tto bodygrou.d in the pMR circuit. Shon to powsr in tha puhp moror pow6rsource circu. r.urty pump motor.etay, FalltyABS contolunit
54ONooc
Open, rhorr ro bodygrcund and/or blown fus€ in the B1 or 82
Shonto body ground.n.Vor short to powor in rhe COM circuitFaulty modul.tor unnFaulty ABS controt unit
ONlgnition voltage (low vott-oooo
. Connection ot the24 V bariorv tor enqins starr. Faurtycharoins system. Op€n in th6lG2 circuit. Fa!lly ABS contrcl unil
81ONCPUoooo
E {€rml facior{sl en bs rhe ouse{sl ot |he probtemF.ulty ABS conrrot unit
r: It DTcs 1 1 18 {wheel sensor codes) wore del*ted the lasr time the v6h cls wEs d riv€n, rhe a8s indicator tight wi
stay on u ntit lh6 ignition swirch is rurn6d oN t), and theconnorunit contnms rhat rhe wheet sensoB . rc OK,
19-58
Troubleshooting
Solenoid
Diagnostic Trouble Code {DTC} 31-38: Solenoid Diagnosis
YES
ABS CONTROL UNIT 22P CONNECTOR
Wire side of female terminals
ABS CONTROL UNIT 26P CONNECTOR
FL.OUT (YEL/ALK)- With the ignition switch ON(lll, ABS indicator light doesnol go oft. or ABS indic.to.light comes on while ABS i3functioning.- With the SCS servico connec-tor connected ls€. pag€ 19-561,DTCa 31-38 are indicstod.
Check for a short lo powor in thosol6noid circuitl1. Disconnect the ABS controlunit 22P and 26P connectors.2. Sta rt the engine.3. Measure the voltage betweenthe ABS control unit connectorappropriate solenoid circuitterminal* and body ground.
Ropri. short to powor in thcappropriate solanoid ci.cuit wirobotw6.n ths ABS cont.ol unitand modulrtor unit.
ls there battery voltage?
Check for a short to body groundin the 3olenoid circuit:Check tor continuity between theappropriate solenoid circuit termi-nal* and body ground.
. Repair short to body ground inlhe .ppropriato solonoid circuitwire betwoan th6 ABS controlunit and modllato. unit.. Replaco the modul.tor unit.
Check th€ ABS control unit:'1. Turn the ignition switch OFF.2. Connect the ABS control unit22P and 26P connectors.3. Connect the SCS service con-
4. Turn the ignition switch ON {ll}.5. Measure the voltage betweenthe ABS control unit 26P con-nector appropriate CONI circuitterminal++ and body ground.
Check for loos€ ABS control unhconnectora. It naceslrry, aub3ti-tutc . known-good ABS controlunit tnd recheck.
ls there approx. 3 V?
DTCAppropriateConnectorAppropriateTerminal
31: FRJN22PNo. 1
32: FR-OUT22PNo.12
33i FL'IN22PNo. 11
34: FL OUT22PNo.10
3s: RRIN26PNo.13
36: RR-OUT22PNo. 21
37: RLIN26PNo.25
38: RL-OUT26PNo.12RL.OUT IYEL}
Wire side of female terminals
DTCAppropriateTerminal
31: FR-lNNo. 2: SCOM
32: FR-OUTNo. 2: SCOM
33i FLINNo. 1: rcOM
34: FL-OUTNo. l: PCOM
35: RR{NNo.1:PCOM
36: RR-OUTNo. 1: rcOM
37rRL'lNNo. 2: SCOM
38: RL-OUTNo. 2: SCOM
RL.OUT (YEL}
19-66
(To page 19-671
tfMain Relay
Diagnostic Trouble Code {DTC} 54: Msin Relay Diagnosis
YES
NOTE: Reinstallthe fuse if it is OK.
ABS CONTROL UNIT 26P CONNECTOR
Wire side of female terminals
ABS CONTROL UNIT 22P CONNECTOR
B1{WHT/GRNI
\e
PCOMIGRN/WHT}scoM{BLK/WHTI
(cont'd)
19-71
Wire side of female terminals
- With the ignition switch ON
{ll), ABS indic.tor light doesnot go off.- With the SCS 3ervica connoc-
tor connected (s€e pag€ 19-561,
DTC 54 is indicated.
checkthe ABS +B (20 Alfuse.
Replace th6 fuso and rechock.
Ch€ck for an op€n in the 81, 82
circuit:Measure the voltage betweenbody ground and the ABS control
unit 26P connector terminal No. '14
and No. 15 individually.
Repair open in the wire betweonthe ABS control unit and under-hood ABS tuse/relav box.
Check for a short lo body ground
in the PMR circuit:1- Turn the ignition switch OFF.
2. Remove the pump motor relay.
3. Disconnect the ABS controlunit 22P connector.4. Check for continuity betweenterminal No. 19 and bodygrouno.
Repair short to body ground in
the wire between the undor-hood ABS fuse/relay box andABS control unit.
ls there continuity?
Check tor a short to body ground
in the PCOM, SCOM circuit:1. Disconnect the ABS controlunit 26P connector.2. Check for continuity betweenbody ground and the ABS con-trol unit 26P terminals No. 1
and No.2 individually.
. Bepai. short to body ground in
tho PCOM circuit wire betwoenthe ABS control unit and under-hood ABS fu3e/.olay box.. Repair 3hort to body ground inthe PCOM or SCOM circuit wirebetween the ABS control unitand moduletor unit.. Rcplace th6 modulator unit.(Short circuit insido tho unit)
ls there continuity?
{To page 19 72)lr
lgnition Voltage
Diagnostic Trouble Code (DTC) 61: lgnhion Voltage Diagno3is
A8S CONTROL UNIT 26P CONNECTOR
IG2IBLK/BLU}
]Wire side of lemale terminals
- With tha engin€ running, ABSindicator lighl is ON.- With the SCS s€rvice connec-to. conn€ctod ls€€ page 19-561,DTC 61 is indicated.
Problem v€rification:1. Erase the DTC.2. Start the engine.3. Make sure that the ABS ind;cator light comes on and DTC61 is indicated.
ls DTC 61 indicated?The system b OK .t this time.
Check the lG2 cilcuii:Measure the voltage between theABS control unit 26P connectorterminal No. 3 and body ground.
ls there 18 V or above?
lf the vohage is 0 V, check lor anopon in the lG2 circuit.It there is 12 - 17 V. substitute aknown-good ABS colrtrol unit andJecheck.
It
19-73