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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 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 using 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 value 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 corrections to the air / fuel mixture computation. A value of 0 indi-
cates no correction, a value greater than 0 means an enrichment correction, and a value less than 0 implies 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. 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 sensor,
IAT sensor, TP sensor, etc.BRAKE SWIgnition switch
ONBrake pedal is depressing ON
Brake pedal is releasing OFF
BLOWER FANIgnition switch
ONBlower fan switch ON ON
Blower fan switch OFF OFF
A/C MAG CLUTCHIgnition switch
ONA/C operating ON
A/C not operating OFF SCAN TOOL DATA CONDITION REFERENCE VALUES
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FUEL TANK LEVEL (%)
This parameter indicates approximate fuel level in the fuel tank. As the detectable range of the fuel level sensor
is set as 0 to 100%, however, with some models whose fuel tank capacity is smaller, the indicated fuel level may
be only 70% even when the fuel tank is full.
PNP SIGNAL (PARK / NEUTRAL POSITION SIGNAL, P/N RANGE or D RANGE)
It is detected by signal from TCM.
D range : A/T is in “R”, “D”, “2” or “L” range.
P/N range : A/T is in “P” or “N” range or the above signal is not inputted from TCM.
EGR VALVE (%)
This parameter indicates opening rate of EGR valve which controls the amount of EGR flow.
PSP SW
The Power Steering Pressure switch parameter displays ON when steering wheel is turned all the way to the
right or left.
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DTC P0110 (DTC No.18) Intake Air Temp. (IAT) Circuit Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode no scan tool and check DTC.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
Low intake air temperature (High voltage-High resistance)
High intake air temperature (Low voltage-Low resistance)“Lg/R” circuit open or shorted to power.
“B/Bl” circuit open
IAT sensor malfunction
ECM malfunction
NOTE:
When DTC P0105 (No.11), P0110 (No.18), P046, P0115 (No.19) and P0120 (No.13) are indicated
together, it is possible that “B/Bl” circuit is open.
Before inspecting, be sure to check that ambient temperature is higher than –40 °C (–40 °F).
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Check IAT Sensor and Its Circuit.
1) Connect scan tool to DLC with ignition
switch OFF. See Fig. 1.
2) Turn ignition switch ON.
3) Check intake air temp. displayed on scan
tool.
Is –40 °C (–40 °F) or 119 °C (246 °F) indicated?Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.
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[A] Fig. 1 for Step 2 / [B] Fig. 2 for Step 3 / [C] Fig. 3 for Step 63 Check Wire Harness.
1) Disconnect IAT sensor connector with igni-
tion switch OFF.
2) Check for proper connection to IAT sensor
at “Lg/B” and “B/Bl” wire terminals.
See Fig. 2.
3) If OK, then with ignition switch ON.
Is voltage applied to “Lg/B” wire terminal about
4 – 6 V?Go to Step 5.“Lg/B” wire open or
shorted to power, or poor
E19-15 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
4 Does scan tool indicate –40 °C (–40 °F) at Step
2.Go to Step 6. Go to Step 5.
5 Check Wire Harness
1) Check intake air temp. displayed on scan
tool with ignition switch ON.
Is –40 °C (–40 °F) indicated?Replace IAT sensor.“Lg/B” wire shorted to
ground.
If wire is OK, substitute a
known-good ECM and
recheck.
6 Check Wire Harness.
1) Using service wire, connect IAT sensor con-
nector terminals.
2) Check intake air temp. displayed on scan
tool with ignition switch ON. See Fig. 3.
Is 119 °C (246 °F) indicated?Replace IAT sensor.“Lg/B” wire open or poor
E19-10 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck. Step Action Yes No
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INSPECTION
[A] Fig. 1 for Step 2 / [B] Fig. 2 for Step 5 / [C] Fig. 3 for Step 6Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Check ECT Sensor and Its Circuit.
1) Connect scan tool with ignition switch OFF.
See Fig. 1.
2) Turn ignition switch ON.
3) Check engine coolant temp. displayed on
scan tool.
Is –40 °C (–40 °F) or 119 °C (246 °F) indicated?Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.
3 Check Wire Harness.
1) Disconnect ECT sensor connector.
2) Check engine coolant temp. displayed on
scan tool.
Is –40 °C (–40 °F) indicated?Replace ECT sensor.“G/B” wire shorted to
ground.
If wire is OK, substitute a
known-good ECM and
recheck.
4 Does scan tool indicate –40 °C (–40 °F) at Step
2.Go to Step 6. Go to Step 5.
5 Check Wire Harness.
1) Disconnect ECT sensor connector with igni-
tion switch OFF.
2) Check for proper connection to ECT sensor
at “B/Bl” and “G/B” wire terminals.
See Fig. 2.
3) If OK, then with ignition switch ON.
Is voltage applied to “B/Bl” wire terminal about
4 – 6 V?Go to Step 4.“G/B” wire open or
shorted to power, or poor
E19-14 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
6 Check Wire Harness.
1) Using service wire, connect ECT sensor
connector terminals. See Fig. 3.
2) Turn ignition switch ON and check engine
coolant temp. displayed on scan tool.
Is 119 °C (246 °F) indicated?Replace ECT sensor.“B/Bl” wire open or poor
E19-10 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
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INSPECTION
[A] Fig. 1 for Step 2 / [B] Fig. 2 for Step 3 / [C] Fig. 3 for Step 4Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Check TP Sensor and Its Circuit.
1) Connect scan tool to DLC with ignition
switch OFF and then turn ignition switch ON.
See Fig. 1.
2) Check throttle valve opening percentage dis-
played on scan tool.
Is it displayed 0% or 100%?Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.
3 Check Wire Harness.
1) Disconnect connector from TP sensor with
ignition switch OFF.
2) Check for proper connection to TP sensor at
“Lg/R”, “Lg” and “B/Bl” wire terminal.
3) If OK, then with ignition switch ON, check
voltage at each of “Lg/R” and “Lg” wire ter-
minals and body ground. See Fig. 2.
Is voltage about 4 – 6 V at each terminal?Go to Step 4.“Lg/R” wire open, “Lg/R”
wire shorted to ground cir-
cuit or power circuit or
“B/Bl” wire, “Lg” wire open
or shorted to ground cir-
cuit or poor E19-22 or
E19-16 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
4 Check TP Sensor.
1) Check resistance between terminals of TP
sensor. See Fig. 3.
TP sensor resistance
Between 1 and 3 : 4.0 – 6.0 k
Ω
ΩΩ Ω
Between 2 and 3 : Varying according to
throttle valve opening (0.02 – 6.0 k
Ω
ΩΩ Ω)
Are measured values within specifications?“B/Bl” wire open or poor
E19-10 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.Replace TP sensor.
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6) Repeat above steps 5) 4 times.
7) Increase vehicle speed to about 50 mph (80 km/h) in 3rd gear or 2 range.
8) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) for
10sec. or more.
9) Stop vehicle (don’t turn ignition switch OFF) and run engine at idle for 2 min. After this step 9), if “Oxygen
Sensor Monitoring TEST COMPLETED” is displayed in “READINESS TESTS” mode and DTC is not dis-
played in “DTC” mode, confirmation test is completed.
If “TEST NOT COMPLTD” is still being displayed, proceed to next step 10).
10) Drive vehicle under usual driving condition for 10 min. (or vehicle is at a stop and run engine at idle for 10
min. or longer)
11) Stop vehicle (don’t turn ignition switch OFF). Confirm test results according to “Test Result Confirmation
Flow Table” in “DTC CONFIRMATION PROCEDURE” of DTC P0420.
INSPECTION
*Usual driving : Driving at 30 – 40 mph, 50 – 60 km/h including short stop according to traffic signal. (under driving condition other than high-load, high-engine
speed, rapid accelerating and decelerating)
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Check exhaust system for leakage, loose con-
nection and damage.
Is it good condition?Go to Step 3. Repair or replace.
3 Check HO2S-2 and Its Circuit.
Was HO2S-2 output voltage indicated on scan
tool in step 3) of DTC confirmation test less
than 1.275 V?Go to Step 4.“B/Bl” or “W” circuit open
or HO2S-2 malfunction.
4 Check Short Term Fuel Trim.
Did short term fuel trim very within –20 – + 20%
range in step 3) of DTC confirmation test?Check “W” and “B/Bl” wire
for open and short, and
connection for poor con-
nection. If wire and con-
nection are OK, replace
HO2S-2.Check fuel system. Go to
DTC P0171 / P0172 Diag.
Flow Table.
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2) Start engine and warm it up to normal operating temperature (70 – 110 °C, 158 – 230 °F) and run it at idle
for 5 min.
3) Increase vehicle speed to 50 – 55 mph, 80 – 88 km/h in 5th gear or in “D” range.
4) Hold throttle valve at that opening position for 2 min. or longer.
5) Increase engine speed to 4000 r/min. in 3rd gear or in “2” range.
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) till
engine speed reaches 1500 r/min.
7) Stop vehicle (don’t turn ignition switch OFF) and confirm test results according to following “Test Result Con-
firmation Flow Table.”
Test Result Confirmation Flow Table
INSPECTION
Step Action Yes No
1 Check DTC in “DTC” mode and pending DTC in
“ON BOARD TEST”.
Is DTC or pending DTC displayed?Proceed to applicable
DTC flow table.Go to Step 2.
2 Set scan tool to “READINESS TESTS” mode
and check if testing has been completed.
Is test completed?No DTC is detected.
(Confirmation test is com-
pleted)Repeat DTC confirmation
procedure.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 1) Turn ignition switch ON.
2) Does EGR stepper motor operation for 0.6
second after ignition switch OFF?Go to Step 3. Go to Step 6.
3 With ignition switch at OFF, check voltage
between E19-28, 17, 29, 18 terminals of ECM
and body ground. See Fig. 2.
Is voltage about 0 V?Go to Step 4. Go to Step 8.