1997 HONDA CR-V o2 sensor

Anti-lock Brake System (ABSI,'97 - 00 Models
Special Tools ............. 19-26
Component Locations ......................... 19-27
Anti-lock Brake System (ABS)
Features/Construction ............. ......, 19-2A
Circuit Diagram ......... 19-32
ABS Control Unit Terminal
Arrangement ......... 19-34
Troubleshooting Precautions ............. 19-36
Diagnostic Trouble Gode (DTC)
Diagnostic Trouble Code (DTC)
Indication (SCS Model ................ 19-38
DTG Erasure (MES Mode) ............... 19-39
Troubleshooting lndex .................... 19-40
Troubleshooting
ABS Indicator Light Does Not
Come On ............ 19-41
ABS Indicator Light Does Not
Go Off (No DTC) ........................... 19-43
DTC 1r - 18:
Wheel Sensor .... 19-45
DTC 31 - 38:
Solenoid ............. 19-47
DTC 51 - 53:
ABS Pump Motor ......................... 19-49
DTC 54:
Main Relay ......... 19-52
DTC 61:
lgnition Voltage ........................... 19-54
DTC 81:
Central Processing Unit (CPU) .... 19-55
Modulator Unit
Removal/lnstallation ....................... 19-56
ABS Control Unit
Replacement ..,...... 19-57
Pulsers/Wheel Sensors
Inspection .............. 19-57
Wheel Sensor Replacement ............ 19-58
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Component Locations
NOTE: The illustrations show the '97 - 98 models. The '99 - 00 models are similar.
ABS CONTROL UNITRIGHT-REAR WHEEL SENSOR
UNDER.HOOD ABSFUSE/RELAY BOX
RIGHT.FRONT WHEELSENSOR CONNECTOR
RIGHT-FRONTWHEEL SENSORRIGHT-REAB WHEELSENSOR CONNECTOR
MODULATOR UNIT
LEFT.FRONT WHEEL SENSOB
UNDER.DASH FUSE,/RELAY 8OX
UNDER.HOOO FUSE/RELAY AOX
IGl I(, AI FUSE
ABS +B 120 Al FUSEPUMP MOTOR ('II AI FUSE
HOBN/STOP I15 AI FUSE
UNDER.HOOD ABS FUSE/RELAY BOX
LEFT.FRONT WHEELSENSOE CONNECTOR
GAUGE ASSEMBLY
ABS INDICATOR
UNDER-DASH FUSE/NELAY BOX
METER {7.5 AI FUSE
MOTOR RELAY
19-27
SERVICE CHECK CONNECTOR {2PI
D!
trtrtr
[r D!
ABS {7.5 AI FUSEMTR CHECK 17.5 AI FUSE
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ABS 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 has three modes: pressure reducing, pressure retaining, and pressure intensi{ying modes.
Self-diagnosis Function
The ABS control unit is equipped with a main cPU and a sub cPU, that check each other for problems.
The CPUs check the circuit of the system.
When the CPUS detect failure, they shift to the "system down mode" or the "control inhibition mode".
The self-diagnosis can be classitied into these four categories:
O: Initial diagnosis
O: Except ABS control
O; During ABS control
@: During warning
On-board Diagnosis Function
The ABS system can be diagnosed with the Honda PGM Tester.
The ALB Checker cannot be used with this system. For air bleeding. and checking wheel sensor signals, use the Honda
PGIM Tester. See the Honda PGM Tester user's manuals for specific operating instructions.
(cont'd)
19-29
ABS CONTROL I-INIT
MODEABSINDICATOR LIGHTMAIN
RE LAY
SOLENOID
VALVERestan conditionDTC
SYSTEM
DOWNONNo
operatron
Drive
inhibitionOperation*rlgnition
switchOFF - oN (ll)Memory
CONTROL
INHIBITIONONNo
operaton
Drive
inhibitionOperationAutomaticlVemory
*1: Except CPU failure
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Wheel Sensor
The wheel sensors are the magnetic contactless type. As the gear pulser teeth rotate past the wheel sensor's magnetic
coil, AC current is generated. The AC frequency changes in accordance with the wheel speed. The ABS control unit detects
the wheel sensor signal frequency and thereby detects the wheel speed
at LOW SPEED
wheel Sp€od and Modulatot Control
VEHICLE SPEED
VEHICLE SPEED
WHEEL SPEED
PRESSU
OUTLETVALVE ON
OFF
INLETVALVE ON
OFF
MOTOR
ON
OFF
When the wheel speed drops sharply below the vehicle speed, the outlet valve opens momentarily to reduce the caliper
fluid pressure. The pump motor starts at this time. As the wheel speed is restored. the inlet valve opens momentarily to
increase the caliDer fluid oressure.
F
GEAR PULSER
19-31
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ABS CONTROL I.]NII {NBK)
Gil
SEFVCE CHEC(STOP
-[rf$-n*'"[m;] t
ra
G2t
rlr*r"t_._*hr;c, ------ r"-!cc
-
Pf:-tL
t=
#
J*tt-
-
55
V-
,ln l'? g,l,BFN+BsN-,| Br(--o-.8:
Y G101cr02
WIT/BLIJ
,r-,,..J A ^ l0lTA L M|; i trr cor'hrEcroF 'r6P)
8LK
4c1013,402
tG2,
Lffi-
_-- -.^ PMR,
t!94
.,._ PCOM,
9
GRN/8I(x
,,-:gLTpliirn
Ilcrom.:C, IRE^R4iq!AGFNmL---l
BLr( -l
eli -.1
BtK-L,-ry
ABs coNTRoL uNrr 26p coNNEcroR 9E-FY!!(o;fib;;; -- coNNF
e -rlr z :ltl,/ a ,18 e tol/ 12li3l I'
| | 4 1 5 16)17 V I1s V l2' VIIU)4 p91ffi
ABS coNTRoL uNrr 22p coNNEcroR QAIA.Li-;;i,;;) -- coNNE
T
t,*---;T- =l------5o ril mtTlI r, / , | #l,'2 -14 i7 19 -)1 .221 | | ,z
Wire side of lemale terminals
)E CHECK:CTOR (2P)
,f
'97
FRO
TermmateINKcroR (16P)
?'--"r""""-./ 6 ,/ 8\
F{ c7
HEEL SENSOR CONNECTOR
model '98-99 models
NT/ REAR FRONTI RIG-HT-REAR
iTtl /J r lz !\
nal side ol Terminal side olterminals male terminals
LEFT.REAR/nf'\1./ 1F
r .4-;1V L:JTerminal side ollemale terminals
19-33
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ABS Control Unit Terminal Arrangement
ABS CONTROL UNIT 26P CONNECTOR
Wire side of female terminals
TeiminalnumbelWiiecolorTerminal3ignTeiminalnamglDescription
Voltrge
tdminalsCondhions(lgnition Switch ON llll)Output voltago
1GRNn/VHTPCOM(Primary
common)
Power source for the solenoidvalve and pump motor.1-GNDON6
ONOV
OFFAC:3-6V
2BLI(WHTSCOM(Secondary
common)
Power source for the solenoid2-GNDOFF
lConnect the SCS seNice] connector IApprox.3 V
BLVBLU(lgnition 2)Detects ignition switch 2signal. (System activate signal)3-GNDBattery Voltage
4BLUA/ELRRO(Rear-right 0)Detocts right-rear wheelsensor srgnat.When the wheel isturned at 1 turn/second.
53 mV or above ondigitaltester (ACrange) {Beference)150 mvtrp or aboveon oscilloscope
GRYRLO(Rear-left 0)Detects left-rear wheel sensorsrgnat.6-19
8GRNFRO(Fronr-right 0)Detects right-front wheelsensor signal.8-21StopsApprox.2.5 VSTOP
{Stop)Detects bfake switch signal.(Prevents unnecessary ABS operation)9-GNDBrake pedal pressed.Battery Voltage
Brake Dedal released.OV
10BRN^/VHTFLO(Front-left 0)
Detects left-front wheel sensorsrgnal.
10-23
When the wheel isturned at 1 turn/second.
53 mV or above ondigitaltester lACrange) (Reference)
150 mvpp or aboveon oscilloscope
StopsADprox. 2.5 V
YELRL-oUT(Rearleft outlet)
Drives left-rear outlet solenoid12.GNDONONOV
OFFAC:3-6V
13RED^/vHTRR.IN(Rear-right
inlet)
Drives right-rear inlet solenoid13.GNDOFF
lConnect the SCS service\ connector IApprox. 3 V
14WHT/GRNB1(Baftery 1)Power source for the solenoidvalve and pump motor.14.GND
Every timeBattery Voltage82(Battery 2)Power source for the solenoidvalve and pump motor.15-GND
16BLKGND2(Ground 2)Ground for the ABS controlunit.16-GNDBelow 0.3 V
't7GRN/YELRR1(Rear-right 1)Detects right-rear wheelsensor signal.'t7 -4
When the wheel is turnedat l turn/second,
53 mV or aboveon digitaltester(AC range)(Reference) 150mVp-p or aboveon oscilloscope
19LT BLURL1(Rearieft 1)Detects left-rear wheel sensorsignal.19-6
GRN/BLKFR1(Front-right 1)Detects right-front wheelsensor srgnat.21-8
23GBN/ORNFL1{Front-left 1}Detects left-front wheel sensorsagnal.23-10StopsApprox. 2.5 V
REDRLI N(Rear-left inlet)
Drives left-rear inlet solenoid
25,GND
ON
=
-9ONOV
AC:3-6V
OFF
/Connect the SCS service] conneclor IApprox. 3 V
26BLKGND3(Gtound 3)Ground tor the ABS controluntI.26-GNDBelow 0.3 V
19-34
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Troubleshooting Precautions
ABS lndicalor
1 lf the system is oK, the ABS indicator goes off two seconds after turning the ignition switch oN 1l) wathout staningthe engine, and then comes on again and goes off after two seconds. This occurs because the ABS control unit isturned on by the lG2 power source.2. The ABS indicator comes on when the ABS control unit detects a problem in the system. However, even thouoh thesystem is operating properly, the ABs indicator will come on too, under the following conditions:. Signal disturbance
. Wheel spin
. Only drive wheels rotate. Battery voltage fluctuates
To determine the actual cause of the problem, question the customer about the problem, taking these conditions intoconsideration:
3 When a problem is detected and the ABS indicator comes on, the indicator can stay on until the ignition switch isturned OFF, or it can automatically go off, depending on the mode.. Indicator stays on untilthe ignition switch is turned off: When the system is in the system down mode.. Indicator automatically goes off: When the system is in the control inhibition mode.4 The ABS indicator stays on when the system is reactivated without erasing the DTC, but it goes off after starting thevehicle.
When the wheel sensor system is faulty and the ABS indicator comes on. the algorithm of the system automatically turnsoff the ABS indicator after the wheel speed signal returns to the normal speed. Also, when the DTc is erased, the cpu isreset and the ABS indicator goes off when the system checked out normal by the initial diagnosis.Therefore, test-drive the vehicle after servicing the wheel sensor system. and be sure that the ABS indicator does notcome on.
5 When the ABS control unit outputs battery voltage to the gauge assembly, the ABS indicator ooes off.
Diagnostic Trouble Code (DTCI
1. The diagnostic trouble code (DTc) is memorized when a problem is detected and the ABS indicator does not go off,or when the ABS indicator comes on.The DTc is not memorized when the ABS indicator 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 tater 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 they 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 procedures toerase the DTCS.
Self-diagnosis
1. Self-diagnosis can be classified into these four categories:' Initial diagnosis: Performed right after the eng ine starts and untir theABS indicator goes off.. 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 is ON.2. The system performs the fo|owing contrors when a probrem is detected by the serf-diagnosis:. ABS indicator ON. Memorv of DTC. Mode changetothe "system down mode,, or the ,,control inhibition mode,,.
MODEABS INDICATORMAIN
RELAY
SOLENOID
VALVECPURestart conditionDTC
SYSTEM
DOWNONNo
operation
Drive
inhibitionOperation*rlgnition
switchoFF - ON l)Memory
CONTROL
INHIBITIONONNo
operal|on
Drive
inhibitionOperationAutomaticlMemory
*1: Except CPU failure
19-36
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Diagnostic Trouble Code (DTC)
Troubleshooting Index
This operation can also be done with the Honda pGM Teste..
*: lf DTcs 11-18 {wheel sensor codes) were detected the last time the vehicle was driven, the ABs indicator wi

stav onuntil the ignition switch is turned ON (ll), and the control unit confirms that the wheel sensors are OK,
19-40
DTC3R DIAGNOSIS/SYMPTOM
DETECTION TIMING
PROBLEM
LOCATION
REFER
TO
PAGE
Io
<=EXzd
8 EE
93gl (J
4,,to 2Ee2
B8
2=
ET63
No
DTC
OFFABS indicator does not come on.19,4'l
ONABS indicator does not go off. (No DTC)19-43't1
oN*Wheel sensor {open/short to body ground/short topower)oooo
FR
19-45
13FL't5RR
17RL
12
oN*Wheel sensor/Pulser (chipped pulser gearlelectrical
notse,ooo
FR
19-45
't4FL
RR
18RL
31
ONSolenoid (open/short to body ground/short topower/stuck)ooo
FR-IN
19-47
32FR-OUT
FL.IN
34FL-OUT
RB-IN
36RR-OUT
37RL-IN
38RL.OUT
ONMotor lockoo19-49
ONMotor stuck OFFoo19-49
53ONMotor stuck ONo19-49
54ONMain relay stuck OFFoooia_at
6lONlgnition voltage (low voltage/high voltage)oooo'19-54
81ONoooo19-55
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