1999 HONDA CR-V Signal light

Fuel Cut-off Control
. During deceleration with the throttle valve closed, current to the fuel injectors iscutoffto improvefuel economyat
speeds over 970 rpm ('97 - 98 models), 920 rpm ('99 - 00 modelsl.
. Fuel cut-off action also takes place when engine speed exceeds 6,500 rpm ('97 - 98 models), 6900 rpm ('99 - 00
models), regardless of the position of the throttle valve, to protect the engine from over-rewing.
With Ay'T model. the PCM cuts the fuel at engine speeds over 5,000 rpm when the vehicle is not moving.*'
4,./C Comoressor Clutch Relav
When the ECM/PCM receives a demand for cooling from the air conditioning system, it delays the compressor from
being energized, and enriches the mixture to assure a smooth transition to the Ay'C mode.
Evaporative Emission (EVAP) Purge Control Solenoid Valve
When the engine coolant temperature is above 154"F (68'C), the ECM/PCM controls the EVAP purge control solenoid
valve which controls vacuum to the EVAP purge control canister,
Alternator Control
The system controls the voltage generated at the alternator in accordance with the electrical load and driving mode.
which reduces the engine load to improve the fuel economy.
PCM Fail-saf e/Back-up Functions
1. Fail-safe Function
When an abnormality occurs in a signal from a sensor, the ECM/PCM ignores that signal and assumes a pre-pre
grammed value for that sensor that allows the engine to continue to run.
2. Back-up Function
When an abnormality occurs in the ECM/PCM itself, the fuel injectors are controlled by a back-up circuit independent
of the system in order to permit minimal driving.
3. Self-diagnosis Function IMalfunction Indicator Lamp (MlL)l
When an abnormality occurs in a signal from a sensor, the ECM/PCM supplies ground for the MIL and stores the DTC
in erasable memory. When the ignition is initially turned on {ll), the ECM/PCM supplies ground for the MIL for two
seconds to check the MIL bulb condition.
4. Two Trio Detection Method
To prevent false indications, the Two Trip Detection Method is used for the HO2S*1, fuel metering-related. idle control
system, ECT sensor and EVAP control system self-diagnostic functions. When an abnormality occurs, the ECM/PCM
stores it in its memory. When the same abnormality recurs after the ignition switch is turned OFF and ON (ll) again,
the ECM/PCM informs the driver by lighting the MlL. However, to ease troubleshooting, this function is cancelled
when you jump the service check connector, The MIL will then blink immediately when an abnormality occurs.
5. Two (or Three) Driving Cycle Detection Method {'97 model)
A "Driving Cycle" consists of starting the engine, beginning closed loop operation, and stopping the engine. lf misfir-
ing that increases emissions or EVAP control system malfunction is detected during two consecutive driving cycles.
or TWC deterioration is detected during three consecutive driving cycles, the ECM/PCM turns the MIL on. However, to
ease troubleshooting, this function is cancelled when you jump the service check connector. The MIL will then blink
immediately when an abnormality occurs.
*1: '97 - 98 models*2: '99 - 00 models
5.
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Alternator (ALT) FR Signal
This signals the ECM/PCM when the Alternator (ALTI is charging.
,97 modet: PCM GONNECTORS
wire side of female terminals
ALT CONNECTOR (C1O5I
lPr-F- ALT F
lll2llw|{frREDl|3.r-'l-
lruueen wne
c (31P|
wire side ol f€male terminals
PCM CONNECTOR C I31P)
3Pr
JUMPERWIRE
Inspection ot ALT FR Signal.
Check lor a short in the wire
{ALT F line}:1. Disconnect the 4P 13Pi* connector from the ALT.2. Turn the ignition switch ON (ll)
3, Measure voltage betweenPCM connector terminals C17
and A9.Check for a short in the wire(ALT F linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat'tery cable from the battery.3. Disconnect PCM connector C(31P).
4. Check for continuity betweenbody ground and PCM connector terminal C17.
ls there approx. 5 V?
Check th€ ope.ation of the ALT:
1. Turn the ignition switch OFF2. Reconnect the ALT 4P {3Pi*connector to the ALT.3. Start the engine. Hold theengine at 3,000 rpm with no
load (in Park or neutral) untilthe radiator fan comes on,
then let it idle.4. Measure voltage betweenPCM connector terminals C17and A9.
Ropeir short in the wir6 betweonthe PCM lC17l and the ALT.
Substitut. a known-good PCM
and recheck. lf prescribed volt-
age is now availablo, replace the
originalPCM.
Does the voltage decrease when
headlights and rear defogger are
turned on?ALT FR signal b OK.
Ch€d( for an op€n in tho wire IALTF linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat-tery cable lrom the battery.3. Disconnect PCM connector C(31P).
4. Disconnect the 4P (3P)* con-nector lrom the ALT.5. Connect the ALT 4P (3P)* con-nector terminal No. 4 (No. 1)*to body ground with a iumper
6. Check for continuity betweenbody ground and PCN4 con'nector terminal Cl7.
Repair open wi.e between thePCM lCl7l and the ALT.ls there continuity?
ALT F IWHT/REDI
Wire side of female terminals
1 1-159
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ldle Gontrol System
Alternator (ALT) FR Signal (cont'dl
'98 - 00 modols:
ALT CONNECTOR (C1I}5I
4P
rH] Arr Fl'l'ltwHr/REo)l3laF1
I JUMPER WIRE JUMPER+ WIRE
ECM/PCM CONNECTORS
Wire side of female terminals
ECM/PCM CONNECTOR C {31PI
Wire side of female terminals
Wire side of female terminals
ECM/PCM CONNECTOR C {31P}
": Canada
1 1-160
B (25P)
Insp€ction of ALT FR Signsl.
Check fo. a shon in th. wire {ALTF linel:1. Disconn6ct the 4P (3P)* con-nector from the ALT.2. Turn the ignition switch ON {ll).3. Measure voltage between ECM/PCM connector terminals C5and 820.Ch€ck for a sho.t in iho wirc lAlTF lino):1. Turn the ignition switch OFF.2. Disconnecl the negative bat,tery cable from the battery.3. Disconnect ECM,PCM connec-torC (31P).
4. Check for continuity betwoenbody ground and ECM/PCMconnector terminal c5.
ls there approx. 5 V7
Check the opcration of the ALT:1. Turn the ignitioo switch OFF.2. Reconnect rhe ALT 4P (3P)*connector to the ALT.3. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator lan comes on,then let it idle.4. Measure voltage between ECM/PCM connector terminals C5and 820.
Roprir lhort in tho wirc bstweentho ECM/PCM {Csl and the ALT.
Substitut. r known-good ECM/PCM and roch.ck. It Droscrib.dvoltage b now lvrilabls, .eplaccth. o.igin!l ECM/PCM.
Does the voltage decrease whenheadlights and rear defogger areturned on?ALT FR 3ignol is OK,
Chock lor an opon in tha wire (ALTF linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat-tery cable from the battery.3. Disconnect ECM/PCM con-nector C (31P).4. Disconnect the 4P 13P)* con,nector from the ALT.5. Connect the ALT 4P {3P)* con-nector terminal No. 4 1No. 1)*to body ground with a jumper
6. Check for continuity betwe€nbody ground and ECM/PCMconnector terminal C5.
Rsprir opan wiro batw.en thoECM/PCM lcsl .nd th. ALT.ls there continuity?
AI.T F IWHT/REDI
ALT F {WHT/REDI
Wire side ot Iemale terminals
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ldle Control System
Brake Switch Signal
This signals the ECM/PCM when the brake pedal is depressed.
('97 model)'- - - - -_- Il
PCM CONNECTORSa t32P) D ll6Pl
BKSW(GRN/WHT)
Wire side of female terminals
Insp€ction of Brak. Switch Signal.
Are the brake lights on withoutpressing the brake pedal?
Inspect the HORN, STOP {15 A)fuse in the undeFhood luse/ relaybox.Do the brake lights come on?
Reoair short in the wire be-tween th€ b.ake switch andth6 HoRN, STOP {15 A)luso,Replaco the HoRN, STOP (15
Al fuse.
Repair op6n in the wir€ be-tween the brake switch andtho HORN, STOP (15 Allus6.Inspect the brrke switch (see
aection l9l.
Check tol .n open in the wire{BXSW linel:1. Press the brake pedal.2. Measure voltage between rcMconnector terminais D5 and Agwith the brake pedal pressed.
Reprir open in the wire betweenthe PcM lD5l rnd the brakeswitch.
(To page 11-167)
1 1-166
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Electronic Control System
The electronic control svstem consists of a Powertrain Control Module (PCM), sensors, a linear solenoid, and four solenoid
valves. Shifting and lock-up are electronically controlled for comfortable driving under all conditions. The PCM is located
below the dashboard, under the kick panel on the passenger's side.
'97 - 98 Mod€ls
PGM.FIControl Sy3t6m
Throttl€ Poshion SensorSignalVehicle Sp.ed SensorSignal
Engino Coolant TamperetureService Check connectorSonsor Signrl
A/T Control Sy3tem
INTERLOCK
Shift Cont.ol
Shift ControlSolenoid valve ACONTROL UNITr
RShift ControlSolenoid Valve B
N
Linear SolenoidDr
Lock-up Control
Ds
Lock-up ControlSolenoid Valve A2
Lock-up ConirolSol6noid valvo B1
M.inshaft Spoed SensorSignel-D! Indicator Light
Count€rahaft Speedsensor SignelSelt-Oiagnosb signel
I
Sell-DiagnosisFunction
l-
{cont'd)
14-15
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Description
PCM
PGM.FIControl System
Throttle Position SensorSignelVehicle Speed SensorSignal
Engin€ Coolsnt TomperatureSen30r SignalService Ch€ck Connectol
A/T Control Svstem
INTERLOCK
Shift Control
Shift ConlrolSolenoid Valve ACONTROL UNITr
RShift ControlSolenoid Valve B
N
Linear SolenoidD
Lock-up Control
2
Lock-up ControlSolenoid valve A1
Lock-up ControlSolenoid Valve BOver-DriveSwitch Signal
Mainshaft Speed SensorSignalE Indicator Light
Countershaft SpeedSensor SigntlSelt-Oiagnosis SigndSelf-DiagnosisFunc{ion
O/D OFFIndicetor Light
Electronic Gontrol System (cont'd)
'99 - 00 Models
14-16
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PCM CONNECTOR B (25P) lcont'd)
PCM CONNECTOR C {31PI
PCM CONNECTOR D II6PI
Terminal NumbelSignalDescriptionMeasuring Conditions/Terminal voltage
811SHBShift control solenoid valve B
control
In E, E position, in 1st and 2nd gear in -q,
Er position: Battery voltage
In B position, in 3rd gear in qd, q:l,in atn
gear in D. position: 0 V
812ILUlnterlock controlWhen ignition switch is ON (ll), brake pedal
deDressed and accelerator oedal released:0 V
B13D4 INDD4 Indicator light controlWhen ignition switch is first turned ON (ll): 6 V
or more for tlvo seconds
In lDll position: 6V or more
814NMSGMainshaft speed sensor ground
815NMMainshaft speed sensor signal
InpuI
Depending on engine speed: Pulsing signal
When engine is stopped: 0 V
816ATP RAy'T gear position switch Eposition signal input
In E position; OV
In other than E position: Battery voltage
817ATP 2Ay'T gear position switch E posi-
tion signal input
InEposition:0V
In other than E position: Battery voltage
B18ATP 1A/T gear position switch El posi-
tion signal input
InEposition:0V
In other than E position: Battery voltage
819 to 821Not used
B22NCSGCountershaft speed sensor ground
NCCountershaft speed sensor signal
Inpur
Depending on vehicle speed: Pulsing signal
when vehicle is stooped: 0 V
824ATP D4A/T gear position switch iql posi-
tion signal input
In E position: 0V
In other than lgal position: Baftery voltage
825ATP NPAy'T gear position switch E and
N position signals input
In E and E positions: 0V
In otherthan @ and ffi positions:5 V
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Voltage
SCSService check signalWith ignition switch ON (ll) and service check
connector open: 5 V
With ignition switch ON (ll) and service check
connector connected with special tool: 0 V
c10VBUBack-up power system(under-hood Fuse 47)
Always battery voltage
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Voltage
STOP SWBrake switch signal inputBrake pedal pressedr Battery voltage
Brake pedal released: 0 V
14-49
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PCM Terminal Voltage/Measuring Conditions
A/T Control System -'98 - 00 Models
The PCM terminal voltage and measuring conditions are shown for the connector terminals that are related to the A"/T con-
trol system. The other PCM terminal voltage and measuring conditions are described in section 11.
FCM Connector Terminal Localions
NOTE: 819 and C3 terminalsare applied to'99 - 00 models.
o (16Pt
T6rminal NumberSignalDescriptionMeasuring Conditions/Terminal Voltage
A5CRSDownshift signal input from
cruise control unit
When cruise control is used; Pulsing signal
A10scsTiming and adjustment service
check signal (5 V from PCM)
With ignition switch ON (ll) and service check
connector open:5 V
With ignition switch ON (ll) and service check
connector jumped with special tool: 0 V
A14('98 model)
D4 INDD4 indicator light control
{Voltage from PCM turns D4 light
oN)
When ignition switch is first turned ON (ll):
Battery voltage for two seconds
In E position: Battery voltage
A14
('99 - 00 models)
D INDD indicator light control(Voltage from PCM turns D light
oN)
When ignition switch is first turned ON (ll):
Baftery voltage for two seconds
ln E position: Battery voltage
428ILUInterlock control(Voltage from PCM)
When ignition switch ON {ll), brake pedal
depressed, and accelerator pedal released:
Battery voltage
A.32STOP SWBrake switch signal inputBrake pedal pressed; Battery voltage
Brake pedal released: 0 V
FCM CONNECTOR B I25P}
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Voltage
B1IGPlPower supply circuit from main
relay via under-hood Fuse 44
With ignition switch ON {ll): Battery voltage
With ignition switch OFF: 0 V
82PG1Ground (G101)
B8LSMLinear solenoid power supply
negative electrode
IG P2Power supply circuit from main
relay
With ignition switch ON (ll): Baftery voltage
With ignition switch OFF: 0 V
810PG2Ground (G101)
B17Linear solenoid power supply
positive electrode
With ignition switch ON (ll): Pulsing signal
819
('99 - 00 models)
O/D INDOver-Drive (O/D) OFF indicator
light control
When ignition switch is first turned ON (ll):
0 V for two seconds
O/D OFF indicator light ON:0 V
O/D OFF indicator light OFF: Battery voltage
s20Ground (G101)
B21VBUBack-up power supply(under-hood Fuse 47)
Always battery voltage
B22LG2Ground (G101)
14-54
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