Meter HONDA CR-V 1997 RD1-RD3 / 1.G Owner's Guide

ECM/PCM Data
By connecting the OBD ll scan tool or the Honda PGM Tester to the 16P data link connector (OLC), various data can be
retrieved from the ECM/PCM. The items listed in the table below conform to the SAE recommended practice
The Honda PGM Tester also reads data beyond that recommended by SAE.
understanding this data will help to find the causes of intermittent failures or engine problems.
NOTE:
The ',operating values" given below are approximate values and may be different depending on the environment and
the individual vehicle.
Unless noted otherwise. "at idle speed" means idling with the engine completely warmed up, transmission in position
Park or neutral and the A,./C and all accessories turned otf.
DataDesc.iptionOp€rating ValuoFreeze Data
Diagnostic
Trouble Code
(DTC)
lf the ECM/PCM detects a problem, it will store it as a
code consisting of one letter and tour numbers
Depending on the problem, an SAE-defined code (Poxxx)
or a Honda-defined code (P'lxxx) will be output to the
tester.
lf no problem is detected,
there is no output.
YES
Engine SpeedThe ECN4/PCN4 computes engine speed from the signals
sent from the Crankshaft Position sensor.
This data is used for determining the time and amount of
fuel iniection.
Nearly the same as
tachometer indication
At idle speed:'97 - 98 models:
750 t 50 rpm'99 - 00 models:
730 f 50 rpm
YES
Vehicle SpeedThe ECM/PCM converts pulse signals from the Vehicle
Speed Sensor (VSSI into speed data.
Nearly the same as
speedometer indicationYES
Manifold
Absolute
Pressure (MAP)
The absolute pressure caused in the intake manifold by
engine load and speed.
With engin6 stopped:
Nearly the same as atmo-
spheric pressure
At idle speed:
2a - 41 kPa {210 - 310
mmHg, 8.3 - 12.2 inHg)
YES
Engine Coolant
Temperature
{ECT)
The ECT sensor converts coolant temperature into volt-
age and signals the ECM/PCM. The sensor is a thermistor
whose internal resistance changes with coolant tempera-
ture. The ECM/PCM uses the voltage signals from the
ECT sensor to determine the amount of injected fuel
With cold engine:
Same as ambient temPer-
ature and IAT
With engine warmed uP:
approx. 163 - 2'12'F
(73 - 100"c)
YES
Heated Oxygen
Sensor (HO25)
(Primary,
Sensor 1)
(Secondary
Sensor 2)
The Heated Oxygen Sensor detects the oxygen content in
the exhaust gas and sends voltage signals to the
ECMiPCM. Based on these signals, the ECM/PCM controls
the airlfuel ratio. When the oxygen content is high (that is.
when the ratio is leaner than the stoichiometric ratio), the
voltage signal is lower.
When the orygen content is low (that is, when the ratio
is richer than the stoichiometric ratio), the voltage signal
is higher.
0.0 - 1.25 V
At idle speed:
about 0.1 - 0.9
NO
(cont'd)
1 1-65
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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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PGM-FI System
Tho Maltunction Indicator Lamo(MlL) n6Yor como3 on leven lortwo laconds) rft6r tho ignhion isturnod ON {lll.
Turn th6 ignition switch ON (ll).
- Repair lhort or opcn in thowire between the No. 25METER 17.5 Al fu3e snd thegauge assembly.- Repl.co the No. 25 METER17.5 Al fus€.
ls the low oil pressure light on?
Try to start the engine.
Chock for an opsn in th€ wiro orbulb {MlL line,:1. Turn the ignition switch OFF.2. Connect the ECM/PCM con-nector terminal A18 to bodyground with a iumper wire.3. Turn the ignition switch ON (ll).
Rep.ir open in the wi.osbotween the ECM/FCM lA18land the gaugo rasombly.Roplece the MIL bulb.
ls th6 MIL on?
Substitute a known-good ECM/PCM and rochock. lf rymptom/indication goes eway, replacetho o gind ECM/PCM.
Turn the ignition switch OFF.Inspect the Fl E/M 115 A) tusein the undeFhood fuse/relaybox.
- Repair short in the wirebetween lhe Fl E/M (15 AlfusG and the PGM-Fl m.in.slay.- Roplsce th€ Fl E/M (15 Alfu3€.
Inspect the No. 13 FUEL PUMP(15 A) fuse in the under-dashfuse/relay box.
- Repair short in th6 wirebetween tho No. 13 FUELPUMP 115 A) luse and thePGM-FI main .elay.- ReDlace tho No. 13 FUELPUMP 115 Al tuse.
Engine Gontrol Module/Powertrain Control Module (ECM/PCM) -'98 - 00 Models
NOTE:. lf this symptom is intermittent, check tor:- A loose Fl E/M {15 A) fuse in the under-hood fuse/relay box- A loose No. 25 METER {7.5 A) fuse in the under-dash fuse/relay box- A loose No. 13 FUEL PUMP (15 Alfuse in the underdash fuse/rolay box- An intermiftent short in the wire between the ECM/PCM (A18) and the gauge assem-
- An int€rmiftent short in the wire between the ECM/PCM (C19) and the MAP sensor- An intermiftent short in the wire between rhe ECM/PCM (C28), the TP sensor, theEGR valve lift sensor and/or {uel tank Dressure sensor- A laulty PGM-FI main relay
ECM/PCM CONNECTOR A (32P}
Wire side of female terminals
(To page 11-871
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Throttle Position (TPl Sensor
The scan tool indicates Diagnostic Trouble Code (DTC) P0122: A low input (voltage) problem in the Throttle
Position (TP) sensor circuit.
The TP Sensor is a potentiometer. lt is connocted to the throttle valve shaft. As the throttle position changes, the throftle
position sensor varies the voltage signal to the ECM/PCM.
'97 mod6l:BRUSHHOI,I'ER
OUTPUT VOLTAGE IVI
5
4
3
2
1
0
THROITLEOPCNIiIG
FUTIIHROTTI"E
TP SENSOR 3P CONNECTOR {Cl3OI
vcc2IYEL/BLUI
Wi.6 6ide ot fgmale terminsls
PCM CONNECTOR D I16PI
Wire side of female terminals
(GRN/BLX)
- The MIL h.3 been reoorted on.- OTC m122 b 3tored.
Problem vorificalion:1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutrall untilthe radiator fan comes on,then turn the ignition switchOFF.2. Turn the ignition switch ON (ll).
3. Check the throttle position
with the scan tool.
ls there approx. 10% when thethrottle is fully closed andapprox.90% when the throttleis fully opened?
Intormittent feilu?e, 3y3tem is OKat thb iime. Check tor poor con-nodiona or loose wiros at C130tTP loNorl .nd rt th€ PCM.
Check tor an open in the wire{vOC2linel:1. Turn the ignition switch OFF.2. Disconnect the TP sensor 3Pconnector,3. Turn the ignition switch ON lll).il. Measure voltage betweenthe TP sensor 3P connector ter-minals No. 1 and No. 3.
ls there approx.5 V?
Check to. an open in wir6 {VCC2linel:Measure voltage between PCMconnector terminals 010 and D11.
Ch6ck to. an opon or shon in TPsonaol:1. Turn the ignition switch OFF.2, At the sensor side, measureresistance between the TPsensor 3P connector terminalsNo. 1 and No. 2 with the throt-tle fully closed.
Repair open in the wirc betweenPCM {D10} and TP 3ensor.ls there approx. 5 V?
Sub3tituto . known-good PCMand rechock. It proscribed volt-ag. b now availablo. rcplaco th6originsl PCM,
Terminal side of male terminals(cont'd)
(To page 11-104)
1 1-103
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PGM-FI System
Random Misfire
lF()gool", tftod-' and some or lpiogol throughTo3oti
The scan tool indicates Diagnostic Trouble Code (DTC)
P0300*,, P1300*1 and some of po30t - pO3O4; Randommisfire.
Descriotion
Misfire detection is accomplished by monitoring the crankshaft speed with the crankshaft speed fluctuation (cKF) sensorwhich is attached to the crankshaft.lfmisfiring strong enough to damage the catalyst is detected, the MIL will blink during the time of its occurrence, and DTcP0300*', P1300*1 and some of DTCs P03ol through P0304 will be stored. Then, after misfire has ceased, the MtL will comeon,
lf misfiring that increases emissions is detected during two consecutive driving cycles, the MIL will come on, and DTcand some of DTCS p0301 through p0304 wi

be stored.NOTE: lf some of the DTCS listed below are stored at the same time as a misfire DTc, troubleshoot those DTcs first. thentroubleshoot the misfire DTC.
P0106, P]128, P1'129; MAp sensorP0171. P0172; Fuet metering
P0505: ldle Control Svstem
P1336, P1337; CKF sensor
P1361, P1362: TDC sensor
Pl381. Pl382: CYP sensor
P1508: IAC valve *1:,97 model*2: '98 - 00 models
Possiblo Caus€
. Fuel pump insufficient fuel pressure, amountofflow. Fuel line clogging. blockage, leakage. Fuel filter clogginga Fuel pressure regulator stuck open. Distributormalfunction
. lgnition coil wire open, leakage. lgnition control module malfunction. Valves carbon deposita Compression lowa Fuel does not meet Owner's Manual spec., lack offuel
Troubleshooting
By test-driving, determine the conditions during which misfire occurs. Depending on these conditions, test in the orderdescribed in the table below.
Possible cause
[ ;;;;- -....
Crankshaft
speed fluctuation
sensor
Fuel
pressureDistributor and
lgnition wirestcMValve
Clearance
Conditionsection 611-178section 23section 23section 6
Only low rpm and load,6)o
Only acceleratingooo
Only high rpm and loado@,a'@
Not specificationG\o@o@
NOTE: lf misfire doesn't recur, some possible causes are fuel that doesn't meet owner's manual spec, lack of fuel, carbondeposits on spark plu9, etc.
11-126
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Vehicle Speed Sensor (VSSI
lPosoo-]-'. |posol l-'
'97 modol:
The scan tool indicates Diagnostic Trouble Code {DTC} P0500*'or P0501*r: A range/perfor-
mance in the Vehicle Speed Sensor (VSS) circuit. * I ; A/T*2i Mfi
FCM CONNECTORS
A t32Pl
LG1(BRN/BLK)
NOTE: Do not use the engine to turn thofront wheels with th6 rear wheels on theground. The 4WD system will engage andthe vehicle will suddenlv Iurch forward.
Wire side ot female terminals
LGl
{BRN/BLKI
(cont'd)
11-135
The MIL hes boen roported on.DTC m501 is 3tor€d.
Problom verificetion:1. Test'drive the vohicle.2. Check the vehicle speed withthe scan tool,
lntormittent tailure, rystom b OKat thia timo. Chock tor poor con-nection3 or 10o3o wires rt C129lvss) .nd rr rhe Pcfr4,
ls the correct speed indicated?
Chock for an open in tho PiCM:1. Turn the ignition switch OFF.2. Block the rear wheels and setthe parking brake.3. Jack up the lront of the vehicleand support it with saletystands.4. Turn the ignition switch ON (ll).
5. Elock the right front wheel andslowly rotate the left trontwheel by hand.6. Measure voltage betweenPCM connector terminals C18and A9.
Substitulc a known-good PCMand .och6ck. It symptom/indicd.tion go.a away, .cplaco tho origi-nel FCM.
Doesthe voltage pulse 0 Vand 5 V or battery voltage?
Check for a .hort in the PCM:L Turn the ignition switch OFF.2. Disconnect the PCM con'nector C (31P).
3. Turn the ignition switch ON (ll).
4. Elock the right front wheeland slowly rotate the left front
5. Measure vohage between PCMconnector terminals C18 andA9.
Substituto e known-good PCMand rochock. f rymptom/indica-tion goos rwry, roplsc. tho origi-nalFCM.
Doesthe voltage pulse 0 Vand 5 V or battery voltage?
- Repair short in the wirebetween the PCM lC18l,cruise control unit, speodo-meter, and VSS,- Repair opon in the wirebetween the PCM {C181 .ndrhe vss.- f wire is OK. tost lho VSS l3oosoction 231.
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ldle Speed Setting
Inspoction/Adiustmont
37 modsl:
NOTE:
. Before setting the idle speed, check the following
items:- The MIL has not been reportsd on.- lgnition timing- Spark plugs
- Air cleaner- PCV system
. lcanada) Pull the parking brake lever up. Stan the
engine, then check that the headlights are off.
1. Start the engine. Hold the engine at 3,000 rpm with
no load (in Park or neutral) until the radiator fan
comes on, then let it idle.
Connect a tachometer or a Honda PGM Tester.
Disconnect the 2P connector from the ldle Air Con-
trol (lAC) valve.
IAC VALVE
lf the engine stalls, restart the engine with the accel-
erator pedal slightly depr6ss6d, Stabilize the rpm at
1,000, then slowly release the pedal until the engine
idles.
Check idling in no-load conditions: hsadlights,
blower fan, rear d€fogger, radiator fan, and air con-
ditioner are not operating.
ldle spood should b.:
{80 t 50 rpm {in Park or noutr.ll
IDLE
7.
Adjust the idle sp6ed,
idle adjusting screw.
if necessary, by turning the
Turn the ignition switch OFF.
Reconnect the 2P connector to the IAC valve, then
remove the BACK UP (RAD|Ol (7.5 Al fuse in the
under-hood fuse/rslav box for 10 seconds to reset
the PCM.
Restart and let the engine idle with no-load condi-
tions for one minute, then check the idle speed.
NOTE: (Canadal Pullthe parking brake lever up. Stan
the engine, then check that the headlights are off.
ldlo Ep€ed rhould be:
75O t 50 rpm (in P.rk or noutr.ll
Let the engine idl6 for one minute with the head-
lights (Low) ON, and check th€ idl€ speed.
ldle lpcod 3hould bo:
750 t 50 ]pm (in Park or nautlal)
Turn the headlights off. Let th€ engine idle for one
minute with the headlights (Low) ON, heater fan
switch at Hl and air conditioner on. then check the idle
sDeeo.
ldl. specd should b6:
7d) 1 50 rpm {in Park or nautral}
lf the idle speed is not within specification, see the
symptom chart on page 11-64. (cont'd)
1 1-169
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ldle Control System
ldle Speed Setting (cont'd)
38 - 0O mod6l3:
NOTE: Before setting the idle speed, check the follow-
ing items:- The MIL has not been reported on.- lgnition timing- Spark plugs
- Air cleaner- PCV system
1. Start the engine. Hold the engine at 3.000 rpm with
no load (in Park or neutral) until the radiator fan
comes on, then let it idle.
Connect a tachometer.
Disconnect the IAC valve 2P connector and the EVAP
purge control solenoid valve 2P connector.
CONTROLSOLENOID VALVE
SOLENOID VALVE
lf the engine stalls, restart the engine with the accel-
erato. pedal slightly depressed. Stabilize the rpm at
1,000, then slowly release the pedal until the engine
idles.
Che€k the idle in no-load conditions: headlights, blow-
er fan, rear defogger, radiator fan, and air conditioner
are not operating,
ldle speed should bo:
480 t 50 rpm {in PErk or noutrall
11-170
lf necessary, adjust the idle speed, by turning the
idle adjusting screw.
After adjusting the idle speed, recheck the ignition
timing (see section 4). lf it is out of spec, go back to
steo 4.tDt.E
6. Turn the ignition switch OFF.
7. Reconnect the 2P connectors to the IAC valve and
the EVAP purge control solenoid valve, then do the
ECM/PCM reset procedure.
8. Restart and idle the engine with no-load conditions
for one minute, then check the idle speed.
ldle speod should be:,98 model:
750 t 50 rpm tin Park or neutral)'9!l - 00 modsls:
730 i 50 lpm lin Psrk or neutral)
NOTE: lf the idle speed increases to 780 t 50 rpm(770 1 50 rpml*, this means the EVAP system is
purging the canister. To stop the purging temporari-
ly, raise the engine speed above 1,000 rpm with the
accelerator pedal, then slowly release the pedal.*: '99 - 00 models
9. Let the engine idle for one minute with the head-
lights (Low) ON, and check the idle speed.
ldle speed should be:
38 mod6l:
750 f 50 rpm (in Palk or neutrall'99 - 00 modols:
730 t 50 rpm (in Palk or neutral)
10. Turn the headlights off. Let the engine idle for one
minute with the heater fan switch at Hl and air con-
ditioner on, then check the idle speed.
ldls spqed should be:'98 model:
780 t 50 rpm (in Park or neutrall'99 - 00 mod€ls:
7701 50 rpm lin Park or neutral)
lf the idle speed is not within specification. see the
Symptom Chart on page 11-64.
ADJUSTING
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Fuel Supply System
Fuel Gauge
Tssting
NOTE: Refer to section 23 for the fuel gauge system cir-cuit diagram.
'1. Check the No. 25 METER (7.5 A) fuse in the under-dash fuse/relay box before testing.
2. Fold the left rear seat cushion forward, and remove
the base frame cover {see section 20).
3. Remove the access panel from the floor.
4. Disconnect the 5P connector from the fuel pump.
5. Measure voltage between the 5P connector termi-nals No.2 and No. 5 with the ignition switch ON ( ).There should be between 5 and 8 V.
FUEL PUMP5P CONNECTOR
tc56al
a
a
Wire side of female t€rminals
lf the voltage is as specified, go to step 6.lf the voltage is not as specified, check for:- an open in the YEUBLK or BLK wrre.- poor ground (c552).
11-184
7.
Turn the ignition switch OFF.
Attach a jumper wire between the No. 2 and No. 5terminals, then turn the ignition switch ON fll).
Check that the pointer of the fuel gauge starts mov-ing toward the "F" mark. Turn the ignition switchOFF before the pointer reaches "F" on the gauge
dial. Failure to do so may damage the luel gauge.
NOTE: The fuel gauge is a bobbin (cross-coil) type,hence the fuel level is continuously indicated evenwhen the ignition switch is OFF, and the pointer
moves more slowly than that of a bimetal type.
. lf the pointer of the fuel gauge does not move atall. replace the gauge.
. lf the gauge is OK, inspect the fuel gauge send-ing unit.
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