1997 HONDA CR-V coolant temperature sensor

The scan tool indicates Diagnostic Trouble Code {DTC) P0118: A high voltage {low temperature) problem in the
Engine Coolant Temperature (ECT) sensor circuit.
ECT SENSOR 2P CONNECTOB (C11ill
ECT(ncD/wlrT)
ECTIREDAAIHT)
Wirc side of lemale terminals
sG2(GRN/8LKI
PCM CONNECTOR D {T6PI
JUMPER WIRE
JUi,IPEB WNE
IGRN/BLX}
Wire side oI female terminals
(cont'd)
1 1-101
The MIL has be€n reported on.DTC P01'18 is stor€d.
Problem verification:1. Turn the ignition switch ON {ll).2. Check the EcT with the scantool-
Intermiftent tailu.€,3ystem is OKat this time, Checl foJ poor con-n€ction3 or loose wires et C1'14(ECT ren3or) and at the ECM/PCM.
ls -4"F (-20'C) or less (or L-Limitin Honda mode ot PGM Tester) or5 V indicated?
Check for an open in the ECT sen-
1. Disconnect the ECT sensor 2Pconnector.2. Connect the ECT sensor 2Pconnector terminals No. 1 andNo. 2 with a jumper wire.3. Check the ECT with the scantool.
ls -4'F (-20'C) or less (or L'Limitin Honda mode of PGM Tester)or5 V indicated?
Check for an open in the wiies{ECT, SG2 lines):1. Turn the ignition switch OFF.2. Connect PCM connector terminals D2 and D11 with a
iumper wire.3. Turn the ignition switch ON {ll}.4. Check the ECT with the scantool,
ls -4"F (-20'C) or less (or L-Limitin Honda mode of PGM Testerior5 V indicated?
Repair open in th6 wire! botwe€nthe PCM lD2, D'l1l and the ECT3€n30t.
('97 model)
(To page 11-102)
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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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EVAP PURGE CONTROL SOLENOID VALVE DUTY CONTROLLED AFTER
STARTING ENGINE
ENGINE COOLANT TEMPERATURE ABOVE 154"F (68'C)
Evaporative Emission (EVAP) Controls
Description:
The evaporative emission controls are designed to minimize the amount of fuel vapor escaping to the atmosphere. The
system consists of the following components:
A. Evaporative Emission (EVAPI Control Canister
An EVAP control canister is used for the temporary storage of fuel vapor until the luel vapor can be purged from the
EVAP control canister into the enqine and burned.
B. Vapor Purge ConirolSystem
EVAP control canister purging is accomplished by drawing fresh air through the EVAP control canister and into a pon
on the intake manifold. The purging vacuum is controlled by the EVAP purge control solenoid valve.
C. Fuel Tank Vapor Control System
When fuel vapor pressure in the fuel tank is higher than the set value of the EVAP two way valve, the valve opens and
regulates the flow ot fuel vapor to the EVAP control canister.
'97 model:
EVAPPURGECONTROL
VALVEFromNo. 15BLK/ /ALTERNATORYEL I sP SENSOR r7.s At(in the under-dashfuse/relay box)
VARIOUSSENSORFEESH AIF
BLK
I
FUEI- TANK
(cont'd)
11-203
INTAKE MANIFOLD
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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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Description
Electronic Control System (cont'dl
Grade Logic Control System
How it works:
The PCM compares actual driving conditions with memorized driving conditions, based on the input from the vehicle speed
sensor, the throttle position sensor, the barometric pressure sensor ('98 model). the engine coolant temperature sensor, the
brake switch signal, and the shift lever position signal, to control shifting while the vehicle is ascending or descending a
slope, or reducing speed.
SIGNALS DETECTED
Driving Rcsisl.nce
Judgemont ot Controlling Aroa
. Normal Modo {Flrt ro.d mode}. Ascending Mode. Deacending Mode. Deceleration Mode
14-14
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Connector ldentification and Wire Harness Routing
Engino Wire Harness
Connecto; or
Terminal
Number of
CavitiesLocationConneqts toNotos
c101
c102
c103
c 104
c105
c105
c106
c 107
c 108
c 109
c]10
c1l'l
c112
c113
c't 14
cl16
cl16
c117
c118
c119
c120
c121
c't22
c't23
c't25
cl26
cl27
cr 28
cl29
c130
c131
c132
c 133
c134
c134
c135
c 136
10
6
1
2
1
2
1
10
20
31
16
22
l0
l0'14
14
1
Left side of engine compartment
Left side of engine compartment
Middle of engine
Middle of engine
Left side of engine compartment
Left side of engine compartment
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Right side of engine
Middle of engine
Behind right kick panel
Under right side of dash
Under right side of dash
Under right side of dash
Under right side of dash
Under right side of dash
Right side of engine
Right side of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Middle of engine
Left side of engine compartment
Middle of engine
Middle of engine
Main wire harness (C304)
Main wire harness (C305):'97 - 98 models
No. 1 fuel injector
Crankshaft speed fluctuation (CKF) sensor
Alternator
Alternator
Engine oil pressure switch
No.2 fuel injector
Evaporative emission (EVAP) purge
control solenoid valve
No. 3 fuel injector
No. 4 fuel injector
Primary heated oxygen sensor(Primary HO2S) (sensor 1)
Radiator fan switch
Coolant temperature sending unit
Engine coolant temperature (ECT) sensor
Mainshaft speed sensor
Lock-up control solenoid valve
Back-up light switch
Shift control solenoid valve
Linear solenoid valve
Countershaft speed sesnsor
Starter solenoid
Distributor
Junction connector
PCM
ECIWPCM
ECM/PCM
ECM/PCM
Main wire harness (C,|:}1)
IVT gear position switch
Vehicle speed sensor (VSS)
Throttle position (TP) sensor
MAP sensor
ldle air control (lAC)valve
lntake air temperature (lAT) sensor
Junction connector
Junction connector
Power steering pressure (PSP) switch
Junction connector
Knock sensor (KS)
A/r
USA
Canada
Alr
AlT
M/'r
Afi
'97mooel
'97 model'98 - 00
mooets
'99 - 00
models
T101
r102
Left side of en0ine companment
Right side of engine compartment
Alternator
Under-hood fuse/relay box
G101Middle of engineEngine ground, via engine wire harness
23-14
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