1997 HONDA CR-V Ignition system

Gharging System
Troubleshooting
lf the charging system light does not come on or does not go off, or the battery is dead or low, test the following items inthe order listed below:
1. Battery (see section 23)
2. Charging system light
3. Voltage
4. Alternator control system (U.S.A. model)
5. Alternator/regulator
Charging System Light Test
ALTERNATOR 4P CONNECTOR{U.S,A. modell
(BLK/YEL)
2
3
Wire sade offemale terminals
I
I
I
ALTERNATOR 3P CONNECTORlCaneda model'
Iemale terminals
[ ]: Canada model
Chsrging Systom Light Check:Turn the ignition switch ON {ll),and make sure the charging system light comes on.
Check for a blown No. 15 17.5 Alfuse and a blown charging sys-tem light bulb. lf the tusa .ndbulb are OK, repair th€ open inth€ WHT/BLU wire.
Does the charging systemlight come on?
Charging System Light Check{com'd}:Start the engine.
Does the charging systemlight go offfPerform the Alte.nator/RegulatorTest lsee page +281.
Voltage Check:Measure the voltage at the No. IlNo. 2iterminal of the 4P [3Plcon-nector with the ignition switch ON{ ).
Ropair the open in the BLK/YELwiae betwoen the altemator andunder-da3h luso/relay box.
ls there battery voltage?
(To next page)
4-24
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in(From previous page)
Does the charging systemlight come on?
Ch6ck the L circuil:1. Turn the ignition switch OFF.2. Disconnect the 4P [3P] con-nector from the alternator.3. Turn the ignition switch ON (ll).
Repair the short to ground in theWHT/BLU wire.
[ ]: Canada model(cont'd)
4-25
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n-
n-
6. Remove the two screws. then remove the switch.
Check for continuity between the terminals in each
switch position according to the table.
. lf there is continuity, and it matches the table,
replace the cable reel.
. lf there is no continuity in one or both positions,
replace the switch.
lf all tests prove OK, reconnect the cable reel sub-
harness connector.
Reconnect the driver's airbag and front passenger's
airbag connectors, and reinstall the access panel on
the steering wheel.
Reconnect the battery positive cable. then the nega-
tive cable.
After connecting the airbag connectors, confirm
proper system operation: Turn the ignition switch ON
(ll); the SRS indicator light should come on for about
six seconds and then go off.
,s
r.
1e
to
7.
l
9.
10.
SET/RESUME
Terminal
t*,r*
-__\l23
SET ION)o----o
RESUME (ON)o----o
11.
4-41
1.
Actuator Test
Disconnect the actuator cable trom the actuator rod
and the 4P connector.
Connect battery power to the No. 4 terminal and
ground to the No. 1, No. 2 and No. 3 terminals,
Connect a vacuum pump to the vacuum hose. Then
apply vacuum to the actuator.
VACUUM PUMP GAUGE0-30 in.Hg.A973X-041-XXXXX
Terminalside otmale terminals
The actuator rod should pull in completely. lf the rod
pulls in only part-way or not at all, check for a leak-
ing vacuum Iine or defective solenoid.
ACTUATOB ROD
(cont'd)
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Goolant Temperature Gauge
Gauge Testing
1. Check the No. 25 (7.5 A) fuse in the under-dash
fuse/relay box before testin9.
2. Make sure the ignition switch is OFF, then discon-
nect the YEL/GRN wire from the coolant tempera-
ture sending unit. and ground it with a jumper wire.
YEL/GRNWIRE
Turn the ignition switch ON {ll). Check that the
pointer of the coolant temperature gauge starts
moving toward the "H" mark. Turn the ignition
switch OFF before the pointer reaches "H" on the
gauge dial. Failure to do so may damage the gauge.
lf the pointer of the gauge does not move at all,
check for an open in the YEL/GRN wire.
lf the wires are OK, replace the coolant temperature
gauge.
lf the coolant temperature gauge works, test the
coolant temperature sending unit.
5.
COOLANT TEMPERATURE
Coolant Temperature Sending Unit
Testing
1. Disconnect the YEUGRN wire from the coolant tem
perature sending unit.
COOLANT TEMPERATURE
POSITIVETERMINAL
YEL/GRN WIRE(Covered withinsulation)
2. Using an ohmmeter, measure the change in resis-
tance between the positive terminal and the engine
(ground) with the engine cold and with the engine
at operating temPerature.
Temperature133.F (56'C)1A5 - 212F
(8s - 100'c)
Resistance(0)13746-30
3. lf the readings are substantially different from the
specitications above, inspect the coolant level and
the cooling system. lf the cooling system is OK,
replace the sending unit.
10-15
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Troubleshooting
Troubleshooting Procedures (cont'd)
DataDescliptionOperating ValueFreezo Data
HO2S
Feedback
Loop Status
Loop status is indicated as "open" or "closed".
Closed: Based on the HO2S output, the ECM/pCM deter-mines the airlfuel ratio and controls the amount ofinjected fuel.
Open: ignoring HO2S output, the ECM/pCiM refers to sig,nals from the TP, MAP, and ECT sensors to control theamount of injected fuel.
At idle speed: closed
YES
Short Term
Fuel Trim
The airlfuel ratio correction coefficient for correcting theamount of injected fuel when HO2S feedback is in theclosed loop status. When the signal from the HO2S isweak, short term fuel trim gets higher, and the ECM/PCMincreases the amount of injected fuel. The airlfuel ratiogradually gets richer, causing a higher HO2S output.Consequently. the short term fuel trim is lowered. andthe ECM/PCM reduces the amount of injected fuel.This cycle keeps the airfuel ratio close to the stoichio-metric ratio when in closed looD status.
t:20y"
YES
Long Term
Fuel Trim
Long term fuel trim is computed from shon term fueltrim and indicates changes occuring in the fuel supplysystem over a long period.
lf long term fuel trim is higher than 1,00. the amount ofinjected fuel must be increased. lf it is lower than L00.the amount of injected fuel must be reduced.
! 20%
Intake Air
Temperature
(IAT)
The IAT sensor converts intake air temperature into volt-age and signals the ECrU/PCM. When intake air tempera-ture is low, the internal resistance of the sensorincreases, and the voltage signal is higher.
With cold engine:
Same as ambient temper-
ature and ECTYES
Throttle
Position
Based on the accelerator pedal position, the openingangle of the throttle valve is indicateo.At idle speed:
approx. 10%
lgnition
Timing
lgnition timing is the ignition advance angle set by theECM/PCM. The ECM/PCM matches ignition timing to thedriving conditions.
At idle speed: 16'1 4.
BTDC with the SCS ser-
vtce connector connected.
NO
Calculated
Load Value(cLV)
CLV is the engine load calculated from the MAp data.At idle speed:
2A - 410/o
At 2,500 rpm with no load:
13 - 260/o
YES
_
1 1_66
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PGM-FI System
System Description
INPUTS
CKP/TDC/CYP Sensor
CKF Sensor
MAP Sensor
ECT Sensor
IAT Sensor
TP Sensor
Primary HO2S
Secondary H02S
vss
KS*5
BARO Sensor
ELD*6
Starter Signal
ALT FR Signal
Air Conditioning Signal
Ay'T Gear Position Signal*1
Baftery Voltage (lGN.1)
Brake Switch Signal
PSP Switch Signal
Fuel Tank Pressuae Sensor*4. *5
Countershaft Speed Sensor*1
Mainshaft Speed Sensor*r
OVER-DRIVE Switch Signal*s
ENGINE CONTROL MODULE (ECM)/
POWERTRAIN CONTROL MODULE (PCM) OUTPUTS
|iuel 1"j""- Th,rhg ""d Drrafr";-l
Et*-.nt"tdt"cont.orl
to,r*,c;;trffi;]
l.----.---:. .Lrgnrnon |lmrng Lonrror I
Ecir/PcM B*k',p Fr""il]
m;"t-ll-r*'io*l
Fuel Injectors
PGM-Fl Main Relay (Fuel Pump)
MIL
IAC Valve
Ay'C Compressor Clutch Relay
Radiator Fan Relay
Condenser Fan Relay
ALT
tcM
EVAP Purge Control Solenoid
Valve
Primary HO2S Heater
Secondary H02S HeaterEVAP Bypass Solenoid Valve*a *5
EVAP Control Canister Vent Shut
DLC
Lock-up Control Solenoid Valve*l
Shift Control Solenoid Valve*1
Ay'T Clutch Pressure Control
Solenoid Valve*1
D4 Indicator Light'1 *3, *a
D Indicator Light,l *5
OVER-DRIVE OFF Indicator
Lighl*t *:
*1: A/T {3:'97 model'2: M/f +4:'98 model*5: '99 - 00 models"6: USA
PGM-Fl System
The PGM-Fl system on this model is a sequential multiport fuel injection system.
Fuel iniecior Timing and Duration
The ECM/PCM contains memories for the basic discharge durations at various engine speeds and manifold pressure. The
basic discharge duration, after being read out from the memory, is further modified by signals sent from various sensors
to obtain the final discharge duration.
ldle Air Control
ldle Air Control Valve (lAC Valve)
When the engine is cold, the Ay'C compressor is on, the transmission is in gear, the brake pedal is depressed, the P/S load
is high, or the alternator is charging, the ECM/PCM controls current to the IAC Valve to maintain the correct idle speed.
lgnition Timing Control
o The ECM/PCM contains memories for basic ionition timing at various engine speeds and manifold air flow rates.
lgnition timing is also adjusted for engine coolant temperature.
. A knock control system was adopted which sets the ideal ig nition timing for the octane rating of the gasoline used.*s
Other Control Funstions
1. Starting Control
When the engine is started. the ECM/PCM provides a rich mixture by increasing fuel injector duration.
2. Fuel Pump Control
. When the ignition switch is initially turned on (ll). the ECMiPCM suppli€s ground to the PGM-FI main relay that
supplies current to the fuel pump for two seconds to pressurize the fuel system.
. When the engine is running, the ECM/PCM supplies ground to the PGM-FI main relay that supplies current to the
fuel oumo.
. When the engine is not running and the ignition is on, the ECM/PCM cuts ground to the PGM-FI main relay which
cuts current to the fuel pump.
1 1-80
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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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PGM-FI System
Powertrain Control Module {PCM} -'97 Model
NOTE: lf this symptom is intermiftent, check for a loose fuse No. 25 METER (7.5 A) in theunderdash f{rse/relay box, a poor connection at PCM terminal A18, or an intermittentopen in the GRN/ORN wire between the PCM (A18) and the gauge assembly.
PCM OON ECTOR A {32P}
Wire side of female terminals
PCM CONNECTOR A {32PI
Wire side ot temale terminals
11-42
The Malfunction lndicator LamD(MlL) nev6r comes on {even lortwo seconds) after ignition isturned on (lll, or it's on dimlyand flickers.
Turn the ignition switch ON {ll}.
- Rep.ir short or opon in thowire batween No. 25 METER(7.5 Alfuso and gauge a$€m-bty.- R6pl.c€ No. 25 METER 17.5 Alfus€.
ls the charging system light on?
Try to stan the engine.
Does the engine start?
Chock tor.n open in th6 wire3{PG1, PG2linesl:1. Turn the ignition switch ON (ll).2. Measure voltage betweenbody ground and PCM con-nector terminals A10 and A23individually.
Check for an op€n in the wir6 orbulb (MlL lin€l:1. Turn the ignition switch OFF.2. Connect the PCM connectorterminal A18 to body groundwith a iumper wire.3. Turn the ignition switch ON {ll).
n€peir open in tho wirelslhwoon PCM and Glol (loc!t.d
at thc tha.mo3tat houling thrthtd moro th.n 1.0 V.
ls thore l€ss than 1.0 V?
Substituto . known-good PCMand r€check. ll symptom/indica-tion goss away, rcplaca the origi-nal PCM.
- R6pai. open in th. wileibelwoon rcM lAl8l dnd g.ugea3rombly.- Roolac€ the MIL bulb.
ls the MIL on?
Substitut6 a known-good PCMand rocheck. ll 3ymptom/indica-tion goes away, replace the o.igi-n.l PCM.
PGl IBLKI
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