1999 HONDA CR-V Coolant temp

ECM/PCM CONNECTOF C (31PI
Wire side o{ female terminal€ECM/PCM CONNECTOR C (31P)NOTE: Standard battery voltage is 12 V.
TermidalD.3criptionSignal
8LI(WHTPOzSHTC {PRIII4ABY HEATEDOXYGEN SENSOR HEATERCONTROL)
Drivss prim6ry h$ted oxygsn sensorWilh ignition switch ON (ll): baneryvoltsgeWith ftrllywarmsd up €ngine runnang: duty
2"WHT/GBNALTC (ALTERNATOR CON,TROL)Sonds alternalor control signsl.With fully wafmod up €ngine rnningr ban€ryvoltagoDu ng driving with small elsctrical lo6d: 0 v
3'1FED/8LUKS (KNOCK SENSOR)Dstects KS signal.With engine knockang: pulses
5WHT/REDALTF (ALTERNATOR FR SIG-NAL}Detects alternator FR signal.Wth fullywarmed up €ngine running:0 V-batteryvoltag€ {d€pending on slsctrical load)
1GRN,4trHTSG1 (SENSOR 680UND}Ground for l/tAP sensor.L€ss than 1.0 v 6t all times
8BLUCKPP (CKP SENSOF P SIDE)Dat€cls CKP s6nsor.With €ngin€ runningr puls€s
9CKPI.,I| {CKP SENSOF M SIDE)Ground for CKP s€nsor.
15PHO2S {PRIMARY HEATEDOXYGEN SENSOR, SENSOR 1)Detocts pfimary he6t6d oxygen ssnsor
{sonsor 1)signal.with ihfottls fully opened from idle with fully,
walm6d up engins: above 0.6 VWith throttlo quickly clossd: below 0.4 v
17RED/GRNMAP (MANIFOLD ABSOLUTEPRESSURE SENSOR)
D6tects MAP s€nsor sign6l.With ignition switch ON (ll):about 3 VAt idls: aboul 1.0 V {dspsnding on engine speed)
18GRN/BLKSG2 (SENSOB GNOUNDiLsss than 1.0 V at all tim€s
19YEUBEDVCCl {SENSOR VOLTAGE)Power soufce to MAP s€nsor.With ignition switch ON (ll): about 5 VWith ignition switch OFF:0 V
20GRNTDCP {TDC SENSOR P SIDE)Derecis TDC sensor.With engine funning: Pulses
2lREDTDCM ITDC SENSOR M SID€)Ground for TDC sensor.
22BLU/REDCKFP (CKF SENSOR PSIDE)Dstscts CKF s€nsor.With sngins running: pulsss
23BLU/WHTVSS (VEHICLE SPEED SEN-soR)Dstscrs vss signal.With ignition switch ON (ll)and front wheelsrotaringrcyclss 0 v- 6bout 5 V or ban€ry voltage
25RED//ELIAT (INTAKE AIR TEMPERA'TURE SENSOB)Detacts IAT sensor signal.With igniiion switch ON (ll): about 0.1 - 4.8 V(d€p€nding on iniate air t€mp€raturc)
26REO/WHTECT {ENCINE COOLANTTEMPERATURE SENSOR)oetscts ECT sensor signal.With ignition switch ON (ll): about 0.1 4.8 V
{doponding on 6ngin€ coolanl lemper6tu16)
27RED/BLKTPS (THROTTLE POSITIONSENSOR)Dotects TP sensor signrl.with rhrottls fully op€n: aboui 4.8 vwith throtrl6 fullyclosed: about 0.5 v
2AYEUBLUVCC2lSENSOR VOLTAG€}Provid€s s€nsor voltage.With ignilion switch ON (ll): about 5 VWhh ignition switch OFF: 0 V
29YELCYPP ICYP SENSO8 P SIDE)Dsrscts CYP sensor.With €ngins runningr pulsss
30BLKCYPM (CYP SENSOR M SIDE)Ground for CYP sansor.
31WHT/REDCKFM {CKF SENSOR M SIDE)6.ound lof CKF ssnsor signal.
11. AfT 13. '94 model'2:M/T 14:'99- 0o modsls.5: USA
(cont'd)
11-73
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Diagnostic Trouble Code (DTCI Chart
*: These DTCS will be indicated by the blinking of the Malfunction Indicator Lamp (MlL) with the SCS service connector
connected.**: The E (E)*u indicator tight and the Malfunction Indicator Lamp (MlL) may come on simultaneously.*1' AIT *3 '97 model +5; '99 - 00 models*2: MlT *4:'98 model
{cont'd)
11-75
DTC(MlL indication*lDetection ltemProbable CausePago
P0107 (3)Manifold Absolute
Pressu.e CircuitLow Input
Open or short in MAP sensor circuit
MAP sensor
ECMiPCM
't 'l-90
P0108 {3)
Manifold AbsolutePressure Circuit
High Input
Open in MAP sensor circuitMAP sensor
ECM/PCM
11-92
P01 1 1*3 (10)Intake Air
Temperature Circuit
Range/Performance Problem
. IAT sensor
11-95
P0112 (10)lntake Air
Temperature CircuitLow Input
Short in IAT sensor circuit
IAT sensorECM/PCM1 1-96
P0113 (10)lntake Air
Temperature Circuit
High lnput
Open in IAT sensor circuit
IAT sensor
ECM/PCM
'I 1-97
P0116 (86)Engine CoolantTemperature CircuitRange/Performance Problem
ECT sensor
Cooling system1 1-99
P0117 (6)Engine Coolant
Temperature Circuit
Low Input
Short in ECT sensor circuit
ECT sensor
ECM/PCM
1 1-100
P0118 (6)Engine Coolant
Temperature CircuitHigh Input
Open in ECT sensor circujt
ECT sensor
ECM/PCM
11-101
P0122 \11
Throttle Position
Circuit
Low Input
Open or short in TP sensor circuitTP sensor
ECM/PCM
11-103
P0123 l7l
Throftle Position
Circuit
High Input
Open in TP sensor circuit
TP sensor
ECM/PCM11-107
P0131 (1)
Primary Heated Oxygen Sensor
Circuit Low Voltage(Sensor 1)
Short in Primary HO2S {Sensor 1)
circuit
Primary HO2S (Sensor 1)
Fuel supply system
ECM/PCM
1 1-1 10
P0132 (1)Primary Heated Orygen SensorCircuit High Voltage(Sensor 1)
Open in Primary HO2S (Sensor 1) circuitPrimary HO25 (Sensor 1)ECM/PCM
'11113
P0133 (61)Primary Heated Oxygen Sensor
Slow Response(Sensor 1)
. Primary HO2S (Sensor 1). Exhaust system11'I 16
P0135 (41)
Primary Heated Oxygen SensorHeater
Circuit Malfunction
{Sensor 1)
. Open or short in Primary HO2S (Sensor'l) heater circuit. ECM/PCM11-12'l
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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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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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PGM-FI System
Engine Coolant Temperature (ECTI Sensor {cont'd)
[F011' The.scan tool indicates Diagnostic Trouble Code (DTC) P0117: A low voltage (high temperature) problem in the: Engine Coolant Temperature (ECT) sensor circuit.
ECT SENSOR 2P CONNECTOR {C114I
Wire side of female terminals
- The MIL has been rooortod on.- DTC ml17 is sto.od.
Problem verification:1. Turn the ignition switch ON {ll).2. Check the ECT with the scantool,
Intermittont f.ilure, sysiom is OKat thk time. Check for poor con-nections or loo3e wire3 at C1lil(ECT sensorl and et the ECM/PCM.
ls 302"F (150'C) or higher (or
H Limit in Honda mode otPGM Tester) or 0 V indicated?
Check for a Bhort in the ECT sen-301:'1. Disconnect the ECT sensor 2Pconnefior,2. Check the ECT with the scantool.
ls 302"F (150"C)or higher (or
H-Limit in Honda mode ofPGM Tester) or 0 V indicated?
Check for r shorl in the wirs(EgT linel:1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector D (16P), (C (31P)*1.3. Check tor continuity betweenthe ECT sensor 2P connectorterminal No. 1 and bodyground.
Repair short in the wir€ betweenthe ECM/FCM (D2, C26rl ,nd th6ECT senaor.
ls there continuity?
Substitute a known-good ECM/PCM and recheck. It normal ECTi! indicatod, replaco the oiiginalECM/PCM.
*:'98 - 00 models
1-1
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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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