1998 HONDA CR-V Coolant hose

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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Engine Goolant Temperature (ECTI Sensor
The scan tool indicates Diagnostic Trouble Code (DTC) P0116: A range/performance problem in the Engine
Coolant Temperature (ECT) Sensor circuit.
The ECT Sensor is a temperature dependant resistor (thermistor). The resistance of the thermistor decreases as the engine
coolant temperature increases as shown below
RESISTANCEtk0l
NOTE: lf DTC P0117 and/or P0118 are stored at the same
bleshoot DTC P0116.
Possible Cause
a ECT sensor deterioration
. Malfunction in the thermostat and cooling system
Troubleshooting Flowchart
-4 32 68 r0a r a0176 212 2aE {'r)-2O O 20 ito tO .o ! t2O I c)
ENGINE COOLANT TEMPERATURE
time as DTC P0116, troubleshoot those DTCS first, then trou-
THERMISTON
- The MIL has be€n roported on.- DTC P01'16 is stored.
Probl6m verification:1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on,then let it idle.2. With the scan tool, check theECT.
Intermittent failure, sYstem b OKat this tim6. Check lhe thermo-stat and the cooling 5y3tom.
ls 176 - 200'F (80 - 93"C) or0.4-0.TVindicated?
Check the thermostat and the
cooling system. It th€y are OK,reolace the ECT seNor.
(cont'd)
1 1-99
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ldle Control System
System Description
The idle speed of the engjne is controlled by the ldle Air Control (lAC) Valve'
The valve changes the amount of air bypassing into the intake manifold in response to electric current controlled by the
ECM/PCM. When the lAc valve is activated, the valve opens to maintain the proper idle speed.
YEL/ From PGM'FI
BLK TMAIN RELAY
VARIOUSSENSORS
4.
IAC VALVE
INTAKE MANIFOLD
After the engine starts, the IAC valve opens for a certain time. The amount of air is increased to raise the idle speed
about 150 - 300 rpm.
when the cootant temperature ts row, the lAc valve is opened to obtain the proper fast idle speed The amount o{
bvoassed air is thus controlled in relation to the engine coolant temperature
When the idle speed is out o{ specification and the scan tool does not indicate Diagnostic Trouble Code (DTC) P0505
or P1508, check the following items:
. Adjust the idle speed (see page 11-169, 170)
. Air conditioning signal (seepagell-1551
. ALT FR signal (see page 1l-159)
. Starter switch signal (see page 11-16'1)
. A,/T gear position signal (see section 14)
. PSP switch signal (seepagell-162)
. Brake switch signal (see page 11-165)
. Fast idlethermovalve (see page'11 168)
. Hoses and connecttons. IAC valve and its mounting O-rings
lf the above items are normat, suDslitute a known-good IAC valve and readjust the idle speed {see page 11-169, 170)
lf the idle speed still cannot be adjusted to specification (and the scan tool does not indicate DTC P0505 or Pl508)
after IAC valve reolacement, substitute a known-good ECM/PCM and recheck lf symptom goes away' replace the
original ECM/PCM.
11-149
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ldle Control System
ldle Control System
I P0505 | The scan tool indicates Diagnostic T.ouble Code (DTCI PO5O5: ldlecontrol svstem mattunction.
NOTE: lf DTC P1508 is stored at the same time as DTC P0505, troubleshoot DTC P1508 first. then troubleshoot DTC p0505.
Possibls Cause
. IAC valve mechanical malfunction. Throttle body clogged port, improper adlustment. Intake manifold gasket leakaging. Intake air hose loose leakaging. Vacuum hose leakaging
a ECT sensor incorrect output. Throttle Position sensor incorrect output
Troubleshooting Flowchart
The MIL has been reDorted on.DTC P0505 is sto.ed.
Problem verificationi1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator Ian comes on, thenlet it idle.2. With the scan tool, check thelollowing items.- Throttle position should beapprox. 10% with the throt-tle {ully closed.- Engine coolant temperature shorJld be 194 - 205'F(90 - 96"C).lf they are not within thespec., repair the faulty sen-sor circuit.3 Check the engine speed atidle with no-load conditions:headlights, blower fan. reardefogger, radiator lan, and airconditioner are not operaling,
Inte.mittent failure. syltem is OKat this time.ls it 750 {730)* i 50 rpm?
ls il 700 (680)' rpm or less?
{To page 11-151)(To page 1'l-151)
l:'99 - 00 models
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Canbter system leak test
{The continuation of DTC P1457
trouble3hootin9.)
Chock the EVAP control canistervent shut valve line and connoc'
tonS:1. Turn the ignition switch OFF
2. Connect to three'way tee fit_
tings into the hose from the
EVAP control canister to the
EVAP two way valve. Connect
the fuel tank pressure sensor
to one of the tee fittings and
the vacuum PumP to the other'
3. Remove the vent hose from
the EVAP control canister vent
shut valve and cap the Pon to
seal the fresh air vent Ior the
EVAP control canister.4. Turn the ignition switch ON (ll).
5. While monitoring the FTP
Sensor voltage with the Honda
PGM Tester, or measurangvoltage between ECM/PCM
connector terminals A29 and
C18 slowly PumP the vacuumpump using a stroke every 1 -
2 seconds.6. Continue to PumP vacuum
until that voltage droPs to
approx. 1.5 V.NOTE: Make sure that the
engine coolant temPeraturestillabove 95'F (35'Cland Yourvacuum PumP has no leak
7. Monitor that voltage for 20
seconds.
Check the EVAP Pu.ge control
solenoid valve line and connec-
tions:1. Turn the ignition switch OFF.
2. Disconnect the Purge lane
hose from the EVAP control
canister and Plug the Port3. Turn the ignition switch ON (lli.
4. While monitoring the FTP
Sensor voltage with the Honda
PGM Tester, or measuringvoltage between ECM/PCM
connector terminals A29 and
Cl8 slowly PumP the vacuumpump using a stroke every 1 -
2 seconds.5. Continue to pump vacuum
until that voltage droPs to
approx. 1-5 V.NOTE: Make sure that the
engine coolant temPeraturestill above 95'F (35"C) and Yourvacuum pump has no leak-
6. Monitor that voltage tor 20
seconds.
Doesthe voltage drop to 1.5 V
and holds at least 20 seconds?
lGp€ct the EVAP control cani3tel
vent 3hut valvo line and connec_
tion5.
Inlpect tho EVAP Putge control
solenoid valvo line and connec'
tion3. It th6y lro OK, do the EVAP
two way valve te3t (seo page 11-
2211.
Does the voltage drop to 1.5 V
and holds at least 20 seconds?
Reolace the EVAP conirol canister.
EVAPBYPASSSOLENOIDVALVE
FUEL TANK
EVAPCONTROL
VENTSHUTVALVE
EVAPCONTROLCANISTER
SENSOR
EVAP TWO WAYVALVE
EVAPTHREE
VALVE
ttrrL
ta
VACUUMPUMP/GAUGE,0 - 30 in.HgA973X -
041 -
XXXXX
FITTINGS
ECM/PCM CONNECTORS
A {32P)
PTANK ILT GRN)
c (31Pt
SG2 {GRN/BLK)
Wire side of female terminals
{cont'd)
11-223
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4. Disconnect the heater hoses from the heater unit.
Engine coolant will run out when the hoses are dis-
connected; drain in into a clean drip pan.
CAUTION: Engino coolant will damage p8int. Ouickly
rinse any spill€d engine coolant Itom painted sur-
faces.
HEATER HOSEIOUTLET SIDE)
Remove the mounting nut from the heater unit.
Take care not to damage or bend the fuel lines, the
brake lines. etc.
CLAMPS
13 N.m 11.3 kg{.m,9.4 lbtftl
22-51
7.
ll.
Remove the dashboard (see section 20).
Remove the evaporator (see page 22-48).
Disconnect the connectors from the mode control
motor and the air mix control motor, and remove the
wire harness clips and wire harness from the heater
unit. Remove the clip from the heater duct, then
remove the mounting nuts and the heater unit
6x1.0mm9,8 N.m (1.0 kgt m,7.2lblft)
qInstall in the reverse order of removal. Make note of
the following items.
a
a
a
a
Apply sealant to the grommets.
Do not interchange the inlet and outlet heater
hoses. Make sure that the clamps are secure.
Refill the cooling system with engine coolant
{see section 10).
Adiust the heater valve cable (see page 22-53).
Make sure that there is no air leakage.
HEATER UNIT
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Gondenser
't.
Replacement
Recover the refrigerant with a recovery/recycling/
charging ststion (see page 22-59)
Remove the front grille (see section 20).
Remove the coolant reservoii, but do not discon-
nect the reservoir hose Jrom the coolant reservoir
and the radiator.
Remove the bolts and the suction line bracket as
shown. Remove the bolts and the upper mount
brsckets from the radiator.
UPPER MOUNTBRACKETS
Remove each bolt, then disconnect the discharge
and condenser lines from the condenser, Plug or
cap the lines immediately after disconnecting them
to avoid moisture and dust contamination.
6x1.0mm9.8 N.m 11,0 kgf.m, 7.2 lbfttl
t\,l/
ait- -:
i..
6x1.0mm
6xl.0mm9,8 N.m 11.0 kgf'm' 7.2lbf'ft)
22-70
DISCHARGE LINE
CONDENS€R LINE
6. Remove the mounting bolts, then remove the con-
denser by lifting it up as shown. Be careful not to
damage the radiator and condenser fins when
removing the condenser.
Install in the reverse order of removal. Make note of
the following items.
. lf you're installing a new condenser, add refriger-
ant oil (sP-10) (see page 22-54]..
o Replace the O-rings with new ones at each fit-
ting, and apply a thin coat of refrigerant oil
before installing them. Be sure to use the right
O-rings for HFC-134a (R-134a) to avoid leakage.
. Be careful not to damage the radiator and con-
denser fins when installing the condenser.
. Be sure to install the lower mount cushions of
condenser securely into the holes,
. Charge the system (see page 22-61), and test its
performance (see page 22-56).
7.
1,0 mm
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