ac system HONDA CIVIC 1999 6.G Workshop Manual

Rear Drum Brake
Brake Shoe Reassembly {cont'dl
Connect the parking brake cable to the parking
brake lever.
Apply grease on each sliding surface.
!@ contaminated brake linings reduce
stopping ability. Keep grease or oil off the blake lin-
ings. Wipe any excess grease off the parts,
. Apply brake cylinder grease {P/N: 08733 - 8020E)
or equivalent rubber grease to the sliding sur-
faces as shown.
+a Sliding surlace
Apply Molykote 44MA to the brake shoe ends and
opposite edges ofthe shoes as shown.
_' o Opposite edge of the shoe+O Brake shoe ends
19-38
13.
5. Clean the threaded portions of clevises A and B.
Coat the threads of the clevises with grease. To
shoften the clevises, tun the adjuster bolt.
6. Hook the self-adjuster spring to the self-adjuster
lever first, then to the brake shoe
7. Install the clevises and upper return spring. noting
the installation direction.
NOTE: Be careful not to damage the wheel cylinder
dust covers,
8. Install the lower return spring.
9. Install the tension pins and retaining springs.
uppER RETURT{ SpRtNG CLEVIS B
CLEVIS A
Installthe brake drum.
lf the wheel cylinder has been removed, bleed the
brake system (see page 19-7), and check for leaks at
brake line connections, and retighten if necessary.
Depress the brake pedal several times to set the
self-adjusting brake.
Adjust the parking brake (see page 19-6).
't0.
11.
12.
LOWER RETURN SPRING

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/

Anti-lock Brake System (ABSI
Featu res/Construction
When the brake pedal is depressed during driving, the wheels can lock before the vehicle comes to a stop, In such a case,the maneuverability of the vehicle is reduced if the front wheels are locked, and the stability of the vehicle is reduced if therear wheels are locked, creating an extremely unstable condition. The ABS precisely controls the slip rate of the wheels toensure the grip force of the tires. and it thereby ensures the maneuverbility and stability of the vehicle.Judging the vehicle speed. the ABS calculates the slip rate of the wheels based on the vehicle speed and the wheel speed,then it controls the brake fluid pressure to attain the target slip rate.
Grip Force of Tire and Road Surlace
COEFFICIENT OFFRICTION
TARGET SLIP RATE
Slip Rate
BRAKINGSTART POINT
ROTATIONALDIRECTION
RADIALDIRECTIONOF THEROTATIONALOIRECTION
A: Distance without slio8: Slippsd distanceC: Actuel distance
sr-rrmre=f=SLIP RATEVEIIICLE SPEED - WHEEL SPEEOVEHICLE SPEED
19-46

t-Operation
t
ABS Control Unit
Main Control
The ABS control unit detects the wheel speed based on the wheel sensor signal it received, then it calculates the vehicle
speed based on the detected wheel speed. The control unit detects the vehicle speed during deceleration based on the
rate of deceleration.
The ABS control unit calculates the slip rate of each wheel. and it transmits the control signal to the modulator unit
solenoid valve when the slip rate is high.
The pressure reduction control is a three-mode system, that is pressure reduction, pressure retaining and pressure intensi-
fying modes.
Self -diagnosis Funqtion
The ABS control unit is equipped with a main CPU and a sub CPU, and the CPUS check each other'
The CPUs check the circuit of the svstem.
When the CPUS detect failure, they shift to the "system down mode" or the "control inhibition mode"
The self-diagnosis can be classifield into these four categories:
O: Initial diagnosis
@: Except ABS control
@: During ABS control
@: During warning
On-board Diagnosis Funstion
The ABS control unit is connected to the data link connector {16P).
The ABS system can be diagnosed with the Honda PGM Tester.
(cont'd)
MODEABS INDICATOR LIGHTMAIN
RELAY
SOLENOID
VALVECPURestart conditionDTC
SYSTE IV
DOWNONNo
operation
Drive
inhibitionOperation*rlgnition
switchOFF + ONMemory
CONTROL
INHIBITIONONNo
operalron
Drive
inhibitionOperationAutomaticMemory
*1: Except CPU failure
/
19-47

Anti-lock Brake System {ABS)
Operation (cont'dl
ABS Modulator
The ABS modulator consists of the inlet solenoid valve, outlet solenoid valve, reservoir, pump, pump motor and thedamping chamber.
The modulator reduces the caliper fluid pressure directly, and it is also referred to as a circulating type because the brake fluidcirculates through the caliper, reservoir and the master cylinder.The hydraulic control has three modes: pressure reducing, pressure retaining, and pressure intensifying.The hydraulic circuit is the independent four channel type, one channel for each wheel.
RF LR
Pressure intensifying mode: Inlet valve open, outlet valve closed
Pressure retaining mode:
Pressure reducing mode:
Motor operation mode:
rN: INLETVALVE {NORMALtY OpENIOUT: OUTIET VALVE {NORMALIY CTOSED)Master cylinder fluid is pumped out to the caliDer.Inlet valve closed, outlet valve closedCaliper fluid is retained by the inlet valve and outlet valve.Inlet valve closed, outlet valve oDenCaliper fluid flows through the outlet valve to the reservoir.When starting the pressure reducing mode, the pump motor is ON.When stopping ABS operation, the pump motor is OFF.The reservoir fluid is pumped out by the pump, through the damping chamber, to the mastercvlinder.
PUMP MOTOR
19-48

ABS Control Unit Terminal Arrangement
ABS CONTROL UNIT 26P CONNECTOR
Wire side of temale terminals
Terminalnumo0rWirecolorTerminal signTerminalnamoDgscriptionVoltage
Conditions(lgnition Switch ON flt))Output voltagoteminals
PCOM(Primary
common)
Power source for the solenoidvalve and pump motor.1-GNDON
=ONOV
AC: 3-6 V
BLK/WHTscoM(Secondary
common)
Power source for the solenoid
2.GNDOFF
lConnect the SCS service\
conneclor lApprox. 3 V
ELVBLUtG2(lgnition 2)Detects ignition switch 2
!9nal. (system activate signal)3-GNDBatt€ry voltage
BLU/YELRRO(Rear-right 0)Detects right-rear wheelsensor signal.4-17
When the wheel isturned at 1 turn/second.
53 mV or above ondigitaltester (ACra nge) {Fefera nce)150 mvp-p or aboveon oscilloscope
6GRYRLO(Rear-left 0)Detects left-rear wheel sensorsrgnal.6-19
8GRNFRO(Front-right 0)D€tects right-front wheelsgnsor srgnal,a-21StopsApprox.2.5VSTOP(Stop)hects brake switch signal.(Prevents unnecess€ry ABS operation)9-GNDBrake pedal depressed.Battery voltage
Brake pedal released.OV
10BRN^/vHTFLO(Front-left 0)
Detects left-front wheel sensorsignal.
10-23
When the wheel isturned at 1 turn/secono.
53 mV or above ondigitaltester (ACrange) (Referance)
150 mVFporaboveon oscilloscope
9!opsApprox. 2.5 V
12YELRLOUT(Rearjeft outlet)
Drives left-rear outlet solenoid
12.GNDON-9ONOV
OFFAC: 3^6 V
REDMHTRR]N(Rear-right
inlet)
Drives right-rear inlet solenoidvalve.13-GNDOFF
lconnect the SCS service]i connector IApprox. 3 V
14B1(Battery 1)Power source for the solenoidvatve and pump motor.14.GND
Battery voltage15WHT/G R N82(Baftery 2)Power source for the solenoidvarve ano pump motor.15.GND
r6BLKGND2{Ground 2)Ground for the ABS controlunit.16-GNDBelow 0.3 V
17GRN/'/ELRR1(Rear-right 1)Detects right-rear wheelsensor signal.17-4
When the wheel is turnedat 1 turn/second.
53 mV or aboveon digitaltester(AC range)(Referance) 150mVp-p or aboveon oscilloscope
19LT BLURLl(Rea.-left 1)Detects left-rear wheel sensorsagnal.19-6
GRN/BLKFRl(Front-right 1)Detects right-front wheelsensor signal.21-8
FL1(Front-left 1)Detects left-front wheel sensorsignal.23-10StopsApprox. 2.5 V
REDRL-IN(Rear-lett inletl
Drives left-r€ar inlet solenoid
25.GND
ut
ON
'6
-9ONOV
OFFAC: 3-6 V
OFF
lconnect the SCS service] connector lApprox. 3 V
BLKGND3(Ground 3)Ground for the ABS cgntrolunit.26.GNDBelow 0.3 V
19-52

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
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
ABS Indicator Light Does Not Come On
YES
NOTE:Reinstallthefuse if it is OK.
The A8S indicator light does not come on when ignition switch is turned ON ll.
NOTE: All indicator tights except the charg,ing system light will not come on when theMETER 17.5 A) ft se is btown.
NO
GAUGE ASSEMBI"Y 5P CONNECTOR
Wire side of female terminals
Tho ABS indicator light does notcome on wh€n ignition switch istu.ned ON {lll.
check the METEB (7.5 A) fuse inthe under-dash fuse/relay box.
Beplace the tu3e and recheck.
Check for an open in th6 lcl cir-cuii:1, Disconnect the gauge assembly 5P connector.2. Turn the ignitjon switch ON l).3. Measure the voltage betweenthe gauge assembly 5P con-nector terminal No. 5 andbody ground.
. Ropair opan in tho wirobotwe€n thc METER t7.5 Attuso and gauge .$cmbly.. Roplacc th. und.r-dash tus./r.l.y box. lop.r cirouit in3idothe box.l
ls there baftery voltage?
Check the ABS indicator lightbulb in the gauge assembly.
ls the bulb OK?
Ch€ck tor a short to power in theWALP circuit:Measure the voltage between thegauge assembly 5P connectorterminal No. I and body ground.
Replir short to power in tho wiiGb.tweon the gruge rs3embly.nd ABS control unh.
ls there battery voltage?
lTo page 19-61)
19-60

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