6-18 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
FAIL-SAFE TABLE
When any of the following DTCs is detected, ECM (PCM) enters fail-safe mode as long as malfunction continues
to exist but that mode is canceled when ECM (PCM) detects normal condition after that.
DTC NO.
DETECTED ITEMFAIL-SAFE OPERATION
P0105Manifold absolute pressure circuit
malfunctionECM (PCM) uses value determined by throttle
opening and engine speed.
ECM (PCM) stops EVAP purge control.
P0110Intake air temp. circuit malfunctionECM (PCM) controls actuators assuming that
intake air temperature is 20C (68F).
P0115Engine coolant temp. circuit malfunction
ECM (PCM) controls actuators assuming that
engine coolant temperature is 80C (176F).
ECM (PCM) operates radiator fan.
ECM (PCM) stops A / C and idle speed control.
P0120Throttle position circuit malfunction
ECM (PCM) controls actuators assuming that
throttle opening is 20.
ECM (PCM) stops idle speed control.
P0500Vehicle speed sensor malfunctionECM (PCM) stops idle air control.
P1450Barometric pressure sensor low /
high inputECM (PCM) controls actuators assuming that
barometric pressure is 100 kPa (760 mmHg).
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-19
Operation
VISUAL INSPECTION
Visually check following parts and systems.
INSPECTION ITEM
REFERRING SECTION
Engine oil ––––– level, leakage
Engine coolant ––––– level, leakage
Fuel ––––– level, leakage
A / T fluid ––––– level, leakage
Air cleaner element ––––– dirt, clogging
Battery ––––– fluid level, corrosion of terminal
Water pump belt ––––– tension, damage
Throttle cable ––––– play, installation
Vacuum hoses of air intake system ––––– disconnection,
looseness, deterioration, bend
Connectors of electric wire harness ––––– disconnection, friction
Fuses ––––– burning
Parts ––––– installation, bolt ––––– looseness
Parts ––––– deformation
Other parts that can be checked visually
Also check following items at engine start, if possible
Malfunction indicator lamp
Charge warning lamp
Engine oil pressure warning lamp
Engine coolant temp. meter
Fuel level meter
Tachometer, if equipped
Abnormal air being inhaled from air intake system
Exhaust system ––––– leakage of exhaust gas, noise
Other parts that can be checked visuallySection 0B
Section 0B
Section 0B
Section 0B
Section 0B
Section 0B
Section 6E1
Section 8
Section 6
Section 6H
Section 8 (section 6 for pressure check)
Section 8
Section 8
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-29
Ambient temp.
SCAN TOOL DATA
As the data values given below are standard values estimated on the basis of values obtained from the normally
operating vehicles by using a scan tool, use them as reference values. Even when the vehicle is in good condition,
there may be cases where the checked value does not fall within each specified data range. Therefore, judgment
as abnormal should not be made by checking with these data alone.
Also, conditions in the below table that can be checked by the scan tool are those detected by ECM (PCM) and
output from ECM (PCM) as commands and there may be cases where the engine or actuator is not operating (in
the condition) as indicated by the scan tool. Be sure to use the timing light to check the ignition timing.
NOTE:
With the generic scan tool, only star () marked data in the table below can be read.
When checking the data with the engine running at idle or racing, be sure to shift M / T gear to the neutral
gear position and A / T gear to the “Park” position and pull the parking brake fully. Also, if nothing or “no
load” is indicated, turn OFF A / C, all electric loads, P / S and all the other necessary switches.
SCAN TOOL DATAVEHICLE CONDITIONNORMAL CONDITION /
REFERENCE VALUES
FUEL SYSTEM B1 (FUEL
SYSTEM STATUS)At specified idle speed after warming upCLOSED (closed loop)
CALC LOAD
(CALCULATED LOADAt specified idle speed with no load after
warming up3 – 5%(
VALUE)At 2500 r / min with no load after warming up10 – 18%
COOLANT TEMP.
(ENGINE COOLANT
TEMP.)
At specified idle speed after warming up85 – 95C, 185 – 203F
SHORT FT BI (SHORT
TERM FUEL TRIM)At specified idle speed after warming up–20 – +20%
LONG FT BI (LONG
TERM FUEL TRIM)At specified idle speed after warming up–15 – +15%
MAP (INTAKE
MANIFOLD ABSOLUTE
PRESSURE)At specified idle speed with no load after
warming up29 – 48 kPa,
220 – 360 mmHg
ENGINE SPEEDAt idling with no load after warming upDesired idle speed
± 50 r / min
VEHICLE SPEEDAt stop0 km / h, 0 MPH
IGNITION ADVANCE
(IGNITION TIMING
ADVANCE FOR NO.1
CYLINDER)
At specified idle speed with no load after
warming up–1 – 18 BTDC
INTAKE AIR TEMP.At specified idle speed after warming up+35C (+63F)
–5C (–9F)
MAF (MASS AIR FLOW
RATE)
At specified idle speed with no load after
warming up1.0 – 3.0 gm / sec
RATE)At 2500 r / min with no load after warming up3.0 – 6.0 gm / sec
THROTTLE POS
(ABSOLUTEIgnition switch ON /Throttle valve fully closed7 – 18%
(ABSOLUTE
THROTTLE POSITION)
g
engine stoppedThrottle valve fully open70 – 90%
O2S B1 S1 (HEATED
OXYGEN SENSOR-1)At specified idle speed after warming up0.05 – 0.95 V
O2S B1 S2 (HEATED
OXYGEN SENSOR-2)When engine is running at 2000 r / min. for
3 min. or longer after warming up.0 – 0.95 V
O2S FT B1 S1At specified idle speed after warning up–20 – +20%
DIS. WITH MIL ON————
6-30 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
SCAN TOOL DATACONDITIONNORMAL CONDITION /
REFERENCE VALUES
DESIRED IDLEAt idling with no load after warming up, M / T850 r / min(DESIRED IDLE SPEED)
gg,
at neutral, A / T at “P” range850 r / min
TP SENSOR VOLT
(THROTTLE POSITIONIgnition switch
ON / engine
Throttle valve fully closedMore than 0.2 V(
SENSOR OUTPUT
VOLTAGE)ON / engine
stoppedThrottle valve fully openLess than 4.8 V
INJ PULSE WIDTH
(FUEL INJECTIONAt specified idle speed with no load after
warming up0.8 – 2.3 msec.(
PULSE WIDTH)At 2500 r / min with no load after warming up0.8 – 2.3 msec.
IAC FLOW DUTY (IDLE
AIR CONTROL FLOW
DUTY)
At idling with no load after warming up20 – 40%
TOTAL FUEL TRIMAt specified idle speed after warming up–35 – +35%
BATTERY VOLTAGEIgnition switch ON / engine stop10 – 14 V
CANIST PRG DUTY
(EVAP CANISTER
PURGE FLOW DUTY)
At specified idle speed after warming up0 – 100%
CLOSED THROT POS
(CLOSED THROTTLEThrottle valve at idle positionON(CLOSED THROTTLE
POSITION)Throttle valve opens larger than idle positionOFF
FUEL CUTWhen engine is at fuel cut conditionONFUEL CUTOther than fuel cut conditionOFF
RAD FAN
(RADIATOR FANIgnition switch
ON
Engine coolant temp.:
Lower than 92.5C
(199F)
OFF
(
CONTROL RELAY)ONEngine coolant temp.:
97.5C (208F) or higherON
ELECTRIC LOAD
Ignition switch ON / Headlight, small light,
heater fan and rear window defogger all
turned OFF
OFF
ELECTRIC LOADIgnition switch ON / Headlight, small light,
heater fan or rear window defogger turned
ON
ON
A / C SWITCH
Engine running after warming up, A / C not
operatingOFF
A/C SWITCHEngine running after warming up, A / C
operatingON
PSP SWITCH
Engine running at idle speed and steering wheel
at straight-ahead position.OFF
(if equipped).Engine running at idle speed and steering wheel
turned to the right or left as far as it stops.ON
FUEL TANK LEVEL––––––––––––0 – 100%
BAROMETRIC PRESS––––––––––––Display the barometric pressure
FUEL PUMP
Within 3 seconds after ignition switch ON or
engine runningON
Engine stop at ignition switch ON.OFF
6-32 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
SCAN TOOL DATA DEFINITIONS
FUEL SYSTEM (FUEL SYSTEM STATUS)
Air / fuel ratio feedback loop status displayed as either
open or closed loop. Open indicates that ECM (PCM)
ignores feedback from the exhaust oxygen sensor.
Closed indicates final injection duration is corrected
for oxygen sensor feedback.
CALC LOAD (CALCULATED LOAD VALUE, %)
Engine load displayed as a percentage of maximum
possible load. Value is calculated mathematically us-
ing the formula: actual (current) intake air volume
maximum possible intake air volume x 100%.
COOLANT TEMP.
(ENGINE COOLANT TEMPERATURE, C, F)
It is detected by engine coolant temp. sensor
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
Short term fuel trim value represents short term
corrections to the air / fuel mixture computation. A val-
ue of 0 indicates no correction, a value greater than
0 means an enrichment correction, and a value less
than 0 implies an enleanment correction.
LONG FT B1 (LONG TERM FUEL TRIM, %)
Long term fuel trim Value represents long term correc-
tions to the air / fuel mixture computation. A value of 0
indicates no correction, a value greater than 0 means
an enrichment correction, and a value less than 0 im-
plies an enleanment correction.
MAP (INTAKE MANIFOLD ABSOLUTE
PRESSURE, kPa, inHg)
It is detected by manifold absolute pressure sensor and
used (among other things) to compute engine load.
ENGINE SPEED (rpm)
It is computed by reference pulses from crankshaft
position sensor.
VEHICLE SPEED (km / h, MPH)
It is computed based on pulse signals from vehicle
speed sensor.
IGNITION ADVANCE
(IGNITION TIMING ADVANCE FOR NO.1
CYLINDER, )
Ignition timing of NO.1 cylinder is commanded by
ECM (PCM). The actual ignition timing should be
checked by using the timing light.
INTAKE AIR TEMP. (C, F)
It is detected by intake air temp. sensor and used to
determine the amount of air passing into the intake
manifold as air density varies with temperature.
MAF (MASS AIR FLOW RATE, gm / s, lb / min)
It represents total mass of air entering intake manifold
which is computed based on signals from MAP sen-
sor, IAT sensor, TP sensor, etc.
THROTTLE POS
(ABSOLUTE THROTTLE POSITION, %)
When throttle position sensor is fully closed position,
throttle opening is indicated as 0% and 100% full open
position.
OXYGEN SENSOR B1 S1
(HEATED OXYGEN SENSOR-1, V)
It indicates output voltage of HO2S-1 installed on ex-
haust manifold (pre-catalyst).
OXYGEN SENSOR B1 S2
(HEATED OXYGEN SENSOR-2, V)
It indicates output voltage of HO2S-2 installed on ex-
haust pipe (post-catalyst). It is used to detect catalyst
deterioration.
DESIRED IDLE (DESIRED IDLE SPEED, rpm)
The Desired Idle Speed is an ECM (PCM) internal pa-
rameter which indicates the ECM (PCM) requested
idle. If the engine is not running, this number is not valid.
TP SENSOR VOLT (THROTTLE POSITION
SENSOR OUTPUT VOLTAGE, V)
The Throttle Position Sensor reading provides throttle
valve opening information in the form of voltage.
INJ PULSE WIDTH
(FUEL INJECTION PULSE WIDTH, msec.)
This parameter indicates time of the injector drive
(valve opening) pulse which is output from ECM
(PCM) (but injector drive time of NO.1 cylinder for
multiport fuel injection).
IAC FLOW DUTY (IDLE AIR (SPEED) CONTROL
DUTY, %)
This parameter indicates opening of the throttle valve
in terms of percentage to opening controllable by the
ISC actuator.
TOTAL FUEL TRIM (%)
The value of Total Fuel Trim is obtained by putting val-
ues of short Term Fuel Trim and Long Term Fuel Trim
together. This value indicates how much correction is
necessary to keep the air / fuel mixture stoichiomet-
rical.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage in-
putted from main relay to ECM (PCM).
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-35
CONNECTOR “C02”
TER-
MINALWIRE
COLORCIRCUITSTANDARD
VOLTAGECONDITION
1BECM (PCM) ground––
2W/BlPower source10 – 14 VIgnition switch ON
3—Blank——
4—Blank——
5—Blank——
6—Blank——
7R/GEVAP canister purge valve10 – 14 VIgnition switch ON
8G/OrShift solenoid B (A / T)
0 VIgnition switch ON, selector lever at “P”
range
8G/OrShift solenoid-B (A / T)
10 – 14 VIgnition switch ON, selector lever at “D”
range
9G/WShift solenoid A (A / T)
0 VIgnition switch ON, selector lever at “P”
range
9G/WShift solenoid-A (A / T)
10 – 14 VIgnition switch ON, selector lever at “D”
range
10OrIgniter (IGT)——
11Gr / YISC actuator——
12Y/BFuel injector10 – 14 VIgnition switch ON
13B/BlGround for injector——
14WPower source for back-up10 – 14 VIgnition switch ON and OFF
15W/BlPower source10 – 14 VIgnition switch ON
16Gr / BISC actuator relay0.3 – 1.0 VIgnition switch ON
17V/YMalfunction indicator lamp0.2 – 2.0 VIgnition switch ON17V/YMalfunction indicator lamp10 – 14 VWhen engine running
18V/GImmobilizer indicator lamp0.2 – 2.0 VIgnition switch ON18V/GImmobilizer indicator lamp10 – 14 VWhen engine running at idle
19Lg / BHeater of H02S-210 – 14 VIgnition switch ON
20BlRadiator fan control relay
10 – 14 VIgnition switch ON, Engine coolant
temp: Below 91.5C (197F)
20BlRadiator fan control relay
0.3 – 1.0 VIgnition switch ON, Engine coolant
temp: 96.0C (205F) or higher
21P/WFuelpumprelay0.3 – 1.3 VFor 2 seconds after ignition switch ON21P/WFuel pump relay10 – 14 VAfter the above time
22Bl / BMain relay0.4 – 1.5 VIgnition switch ON
23–Blank——
24Gr / RISC actuator——
25Y/REFE heater relay10 – 14 VIgnition switch ON
26B/RGround for injector——
6-36 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
CONNECTOR “C01”
TER-
MINALWIRE
COLORCIRCUITSTANDARD
VOLTAGECONDITION
1LgPower source for sensor4.75 – 5.25 VIgnition switch ON
2OrCamshaft position sensor (+)——
3W/BCrankshaft position sensor
(+)——
4Gr / GClosed throttle position switch
0 – 1 V
Ignition switch ON, ISC actuator
plunger is in contact with throttle lever
screw
4Gr / G(In ISC actuator)
4 – 6 V
Ignition switch ON
Plunger is apart from throttle lever
screw
5Lg / RManifold absolute pressure
sensor3.3 – 4.0 V
Ignition switch ON
Barometric pressure: 100 kPa,
760 mmHg
6Lg / WThrottle position sensor
0.2 – 1.0 V
Ignition switch ON, when clearance
between throttle lever and throttle stop
screw is less than 0.35 mm (0.014 in.)
2.8 – 4.8 VIgnition switch ON
Throttle valve at full open position
7Gr / WEngine coolant temp. sensor0.55 – 0.95 VIgnition switch ON
Engine coolant temp.: 80C (176F)
8P/BHeater of H02S-110 – 14 VIgnition switch ON
9GGround for sensors——
10WCamshaft position sensor (–)——
11W/RCrankshaft position sensor
(+)——
12W/BEFE heater monitor0 – 1 VHeater relay OFF12W/BEFE heater monitor10 – 14 VHeater relay ON
13RHeated oxygen sensor-1Refer to DTC flow chart
14GrIntake air temp. sensor2.0 – 2.7 V
Ignition switch ON
Sensor ambient temp.
(Intake air temp): 20C (68F)
10 – 14 VIgnition switch ON
15Bl / WPower steering pressure
switch (If equipped)
0 – 1 V
With engine running at idle speed,
turning steering wheel to the right or left
as far as it stops, repeating it a few
times
16B/YEngine start switch6 – 12 VWhile engine cranking16B/Yg
(Engine start signal)0 – 1 VOther than above
ECT sensor
To combination
(ECT) meterTo other sensors
6-48 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0115 ENGINE COOLANT TEMPERATURE (ECT) CIRCUIT
MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
Low engine coolant temperature (High voltage-High resistance)
or
High engine coolant temperature (Low voltage-Low resistance)“Gr / W” circuit open or shorted to power
“G” circuit open
ECT sensor malfunction
ECM (PCM) malfunction
NOTE:
Before inspecting, be sure to check that coolant temp. meter in combination meter indicates normal oper-
ating temperature (Engine is not overheating).
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode on scan tool and check DTC.