air condition ISUZU TF SERIES 2004 Workshop Manual

6E-80 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Tech 2
Parameter
Units Idle 2000rpm Definitions
23 A/C Request (Air
Conditioning) On/Off Off Off This displays the air conditioner request signal. This should display "On" when the air
conditioner switch is switched on.
24 A/C Clutch On/Off Off Off This displays whether the ECM has commanded the A/C compressor clutch "On" or
"Off".
25 EVAP Purge
Solenoid
(Evaporative
Emission) % 50
80 0 This displays the duty signal from the ECM to control the canister purge solenoid
valve.
26 Fuel Trim Cell 49
52 13
17 This displays dependent on engine speed and MAF sensor reading.
A plot of engine speed versus MAF amount is divided into the cells.
Fuel trim cell indicates which cell is currently active.
27 Fuel Pump On/Off On On This displays operating status for the fuel pump main relay.
This should display "On" when the key switch is turned on and while engine is
running.
28 Deceleration Fuel
Cutoff Active/ Inactive Inactive Inactive The ECM will command the deceleration fuel mode when it detects a closed throttle
position while the vehicle is traveling.
While in decreasing fuel mode, the ECM will decrease the amount of fuel delivered
by entering open loop and decreasing the injector pulse width.
29 Power Enrichment Yes/No No No The ECM will command power enrichment mode "Yes" when a large increase in
throttle position and load is detected.
While in power enrichment mode, the ECM will increase the amount of fuel delivered
by entering open loop and increasing the injector pulse width.
30 Vehicle Speed km/h or mph 0 0 This displays vehicle speed.
The vehicle speed is measured by ECM from the vehicle speed sensor.
31 Cam Signal Present/ Missing Present Present This displays input signal from the camshaft position sensor.
When the correct pulse is generated, signal is received.
32 PSP Switch
(Power Steering
Pressure) Normal Pressure /
High Pressure Normal PressureNormal PressureThis displays the power steering pressure signal.
This should display "High Pressure" when the steering is steered.
33 Security Code
Status Programmable/
Not
Programmable Programmable Programmable This should display "Programmable" when the correct security code & secret code
are programmed.
34 Security Code Okay/ Not Okay Okay Okay This should display "Okay" when the security code is correctly accepted.
35 Immobilizer
System Normal /
Abnormal Normal Normal This should display "Normal" when the immobilizer is correctly operated.
36 Malfunction
Indicator Lamp On/Off Off Off This displays operating status for the Check Engine Lamp.
This should display "On" when the Check Engine Lamp is turned on.
37 Time From Start   This displays the engine time elapsed since the engine was started.
If the engine is stopped, engine run time will be reset to 00:00:00

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-81
TYPICAL SCAN DATA & DEFINITIONS (O2 SENSOR DATA)
Use the typical values table only after the On-Board Diagnostic System check has been completed, no DTC(s) were noted, and you have determined that the On-Board
Diagnostic are functioning properly.
Tech2 values from a properly running engine may be used for comparison with the engine you are diagnosing.
Condition : Vehicle stopping, engine running, air conditioning off & after warm-up (Coolant temperature approximately 80
C)

Tech 2
Parameter
Units Idle 2000rpm Definitions
1 Ignition Voltage V 10.0  14.5 10.0  14.5 This displays the system voltage measured by the ECM at ignition feed.
2 Engine Speed rpm 710  860 1950  2050 The actual engine speed is measured by ECM from the CKP sensor 58X signal.
3 Desired Idle
Speed rpm 750  770 750  770 The desired engine idle speed that the ECM commanding.
The ECM compensates for various engine loads.
4 Engine Coolant
Temperature
C or
F 80  90 (
C) 80  90 (
C) The ECT is measured by ECM from ECT sensor output voltage.
When the engine is normally warm upped, this data displays approximately 80 °C or
more.
5 Start Up ECT
(Engine Coolant
Temperature)
C or
F Depends on ECT
at start-up
Depends on ECT
at start-up
Start-up ECT is measured by ECM from ECT sensor output voltage when engine is
started.
6 Throttle Position % 0 4  6 Throttle position operating angle is measured by the ECM from throttle position
output voltage.
This should display 0% at idle and 99  100% at full throttle.
7 Throttle Position
Sensor V 0.4  0.7 0.6  0.8 The TPS output voltage is displayed.
This data is changing by accelerator operating angle.
8 Mass Air Flow g/s 5.0  8.0 13.0  16.0 This displays intake air amount.
The mass air flow is measured by ECM from the MAF sensor output voltage.
9 Air Fuel Ratio 14.7:1 14.7:1 This displays the ECM commanded value. In closed loop, this should normally be
displayed around 14.2:1  14.7:1.
10 Engine Load % 2  7 8  15 This displays is calculated by the ECM form engine speed and MAF sensor reading.
Engine load should increase with an increase in engine speed or air flow amount.
11 B1 Fuel System
Status Open Loop/ Close
Loop Close Loop Close Loop
12 B2 Fuel System
Status Open Loop/ Close
Loop Close Loop Close Loop
When the engine is first started the system is in "Open Loop" operation.
In "Open Loop", the ECM ignores the signal from the oxygen sensors.
When various conditions (ECT, time from start, engine speed & oxygen sensor
output) are met, the system enters "Closed Loop" operation.
In "Closed Loop", the ECM calculates the air fuel ratio based on the signal from the
oxygen sensors.
13 B1S1 O2 Sensor
(Bank1 Sensor 1)
mV 50  950 50 950
14 B2S1 O2 Sensor
(Bank2 Sensor 1)
mV 50  950 50  950
This displays the exhaust oxygen sensor output voltage.
Should fluctuate constantly within a range between 10mV (lean exhaust) and
1000mV (rich exhaust) while operating in closed loop.
15 B1 O2 Sensor
Ready (Bank 1)
Yes/No Yes Yes
16 B2 O2 Sensor
Ready (Bank 2)
Yes/No Yes Yes
This displays the status of the exhaust oxygen sensor.
This display will indicate "Yes" when the ECM detects a fluctuating oxygen sensor
output voltage sufficient to allow closed loop operation.
This will not occur unless the oxygen sensor is warmed up.
17 B1 Long Term
Fuel Trim (Bank
1)
% -10  20 -10  20
18 B2 Long Term
Fuel Trim (Bank
2)
% -10  20 -10  20
The long term fuel trim is delivered from the short term fuel term values and
represents a long term correction of fuel delivery for bank in question.
A value of 0% indicates that fuel delivery requires no compensation to maintain the
ECM commanded air fuel ratio.
A negative value indicates that the fuel system is rich and fuel delivery is being
reduced (decreased injector pulse width).
A positive value indicates that a lean condition exists and the ECM is compensating
by add fuel (increased injector pulse width).
Because long term fuel trim tends to follow short term fuel trim, a value in the
negative range due to canister purge at idle should not be considered unusual.
Excessive long term fuel trim values may indicate an rich or lean condition.

6E-82 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Tech 2
Parameter
Units Idle 2000rpm Definitions
19 B1 Short Term
Fuel Trim (Bank
1)
% -10
20 -10
20
20 B2 Short Term
Fuel Trim (Bank
2)
% -10
20 -10
20
The short term fuel trim to a bank represents a short term correction to the bank fuel
delivery by the ECM in response to the amount of time the bank fuel control oxygen
sensor voltage spends above or below the 450mV threshold.
If the oxygen sensor voltage has mainly remained less than 450mV, indicating a lean
air/fuel, short term fuel trim will increase into the positive range above 0% and the
ECM will pass fuel.
If the oxygen sensor voltage stays mainly above the threshold, short term fuel trim
will decrease below 0% into the negative range while the ECM reduces fuel delivery
to compensate for the indicated rich condition.
Under certain conditions such as extended idle and high ambient temperatures,
canister purge may cause short term fuel trim to read in the negative range during
normal operation.
Excessive short term fuel trim values may indicate an rich or lean condition.
21 Fuel Trim Cell 49
52 13
17 This displays dependent on engine speed and MAF sensor reading.
A plot of engine speed versus MAF amount is divided into the cells.
Fuel trim cell indicates which cell is currently active.
22 Fuel Trim
Learned (Bank 1) Yes/No Yes Yes
23 Fuel Trim
Learned (Bank 2) Yes/No Yes Yes
When conditions are appropriate for enabling long term fuel trim corrections, fuel trim
learn will display "Yes".
This indicates that the long term fuel trim is responding to the short term fuel trim.
If the fuel trim lean displays "No", then long term fuel trim will not respond to changes
in short term fuel trim.
24 B1S1 Status
(Bank 1 Sensor 1)
Rich / Lean Rich / Lean Rich / Lean
25 B2S1 Status
(Bank 2 Sensor 1)
Rich / Lean Rich / Lean Rich / Lean
This displays dependent on the exhaust oxygen sensor output voltage.
Should fluctuate constantly "Rich" and "Lean" in closed loop.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-119
Fuel System Diagnosis

Step Action Value(s) YES NO
1
Was the “On-Board Diagnostic (OBD) System Check"
performed? — Go to Step 2 Go to OBD
System Check
2
1. Turn the ignition “OFF."
2. Turn the air conditioning system “OFF."
3. Relieve fuel system pressure and install the fuel
pressure gauge.
Refer to 6E-118 FUEL GAUGE INSTALLATION
4. Turn the ignition “ON."
NOTE: The fuel pump will run for approximately 2
seconds. Use the Tech 2 to command the fuel
pump “ON".
5. Observe the fuel pressure indicated by the fuel
pressure gauge with the fuel pump running.
Is the fuel pressure within the specified limits? 290-376 kPa
(42-55 psi) Go to Step 3 Go to Step 17
3
The fuel pressure will drop when the fuel pump stops
running, then it should stabilize and remain constant.
Does the fuel pressure indicated by the fuel pressure
gauge remain constant? — Go to Step 4 Go to Step 12
4
1. When the vehicle is at normal operation
temperature, turn the ignition “ON" to build fuel
pressure and observe the measurement on the
gauge.
2. Start the engine and observe the fuel pressure
gauge.
Did the reading drop by the amount specified after the
engine was started? 21-105 kPa
(3-15 psi) Go to Step 5 Go to Step 9
5
Is fuel pressure dropping off during acceleration,
cruise, or hard cornering? — Go to Step 6 Check for
improper fuel
6 Visually and physically inspect the following items for
a restriction:
 The in-line fuel filter.
 The fuel feed line.
Was a restriction found? — Verify repair Go to Step 7
7 Remove the fuel tank and visually and physically
inspect the following items:
 The fuel pump strainer for a restriction.
 The fuel line for a leak.
 Verify that the correct fuel pump is in the vehicle.
Was a problem found in any of these areas? — Verify repair Go to Step 8

6E-122 3.5L ENGINE DRIVEABILITY AND EMISSIONS
A/C SYSTEM CIRCUIT DIAGNOSIS



RTW36EMF000101

CIRCUIT DESCRIPTION
When air conditioning and blower fan are selected, and
if the system has a sufficient refrigerant charge, a
12-volt signal is supplied to the A/C request input of the
Engine Control Module (ECM). The A/C request signal
may be temporarily canceled during system operation
by the electronic thermostat in the evaporator case. The
electronic thermostat may intermittently remove the
control circuit ground for the A/C thermostat relay to
prevent the evaporator from forming ice. When the A/C
request signal is received by the ECM, the ECM
supplies a ground from the compressor clutch relay i
f
the engine operating conditions are within acceptable
ranges. With the A/C compressor relay energized,
voltage is supplied to the compressor clutch coil.
The ECM will enable the compressor clutch to engage
whenever A/C has been selected with the engine
running, unless any of the following conditions are
present:

 The A/C request switch is "Off".
 The engine speed is lower than 550rpm or greate
r
than 6375rpm.
 The engine coolant temperature is greater than
120
.
DIAGNOSTIC AIDS
To diagnose an the intermittent fault, check for the
following conditions:
 Poor connection at the ECM–Inspect connections fo
r
backed-out terminals, improper mating, broken locks,
improperly formed or damaged terminals, and poo
r
terminal-to-wire connection.
 Damaged harness–Inspect the wiring harness fo
r
damage. If the harness appears to OK, observe the
A/C clutch while moving connectors and wiring
harnesses related to the A/C. A sudden clutch
malfunction will indicate the source of the intermitten
t
fault.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-123
A/C CLUTCH DIAGNOSIS
This chart should be used for diagnosing the electrical
portion of the A/C compressor clutch circuit. A Tech 2
will be used in diagnosing the system. The Tech 2 has
the ability to read the A/C request input to the ECM. The
Tech 2 can display when the ECM has commanded the
A/C clutch “ON." The Tech 2 should have the ability to
override the A/C request signal and energize the A/C
compressor relay.




A/C Clutch Control Circuit Diagnosis
Step Action Value (s) Yes No
1
Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go to On Board
Diagnostic (OBD)
System Check
2
Are the A/C setting conditions met?
- Go to Step 3 Set the setting
condition and Go
to Step 3
3
Is the A/C compressor worked properly?
- Diagnosis
completed Go to Step 4
4
Does the blower motor operate?
- Go to Step 6 Go to Step 5
5
Repair the blower motor circuit.
Is the action complete?
- Verify repair -
6
1. Using the Tech 2, ignition "On" and engine "On".
2. Select the "Miscellaneous Test" and perform the
"A/C Clutch Relay" in the "Relays".
3. Operate the Tech 2 in accordance with procedure.
Was the A/C compressor magnet clutch engaged,
when the Tech 2 is operated?
- Go to Step 15 Go to Step 7
7
Check the "A/C" fuse (10A). If the fuse is burnt out,
repair as necessary.
Was the problem found?
- Verify repair Go to Step 8

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-131

Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure Parts Related
ECM Pin
No. Related
Multiple
DTC
P0101 B Mass Air Flow Sensor Circuit
Range/Performance 1. No DTC relating to barometer sensor, TPS,
CMP sensor, CKP sensor and MAF sensor
(low input & high input).
2. Engine speed is between 2800rpm and
4500rpm.
3. Throttle position sensor output voltage is
between 1V and 3V.
4. Intake air temperature is between -14
C and
70
C.
5. Air flow amount below 0.04g/s (small air) or
more than 177g/s (large air). Above
conditions are met for 3 seconds. No fail-safe function. Air flow amount is more than
0.04g/s or below 177g/s. 1. Air intake is obstructed.
2. Sensor signal circuit short to voltage circuit.
3. MAF sensor malfunction.
4. Electrical interference.
5. ECM malfunction. B20/
B39 - P0102 A Mass Air Flow Sensor Circuit
Low Input MAF sensor output voltage is below 0.3V. MAF sensor output voltage is
more than 0.3V. 1. Sensor power supply circuit open circuit.
2. Sensor signal circuit open or short to ground
circuit.
3. Poor connector connection.
4. MAF sensor malfunction.
5. ECM malfunction. B20 -
61
P0103 A Mass Air Flow Sensor Circuit
High Input MAF sensor output voltage is more than 4.9V. The ECM uses default mass
air flow value based on IAC
valve position, throttle position,
barometer pressure and
engine speed.
MAF sensor output voltage is
below 4.9V. 1. Sensor signal circuit short to voltage circuit.
2. Sensor ground circuit open or short to voltage
circuit.
3. MAF sensor malfunction.
4. ECM malfunction. B20/
B39 P0113/
P0123/
P0341/
P0342
P0112 A Intake Air Temperature Sensor
Low Input IAT sensor output voltage is below 0.08V. IAT sensor output voltage is
more than 0.08V. 1. Sensor signal circuit short to ground circuit.
2. IAT sensor malfunction.
3. ECM malfunction. A19 -
23

P0113 A Intake Air Temperature Sensor
High Input IAT sensor output voltage is more than 4.9V. The ECM use 40
C conditions
as substitute.
IAT sensor output voltage is
below 4.9V. 1. Sensor signal circuit open or short to voltage
circuit.
2. Sensor ground circuit open or short to voltage
circuit.
3. Poor connector connection
4. IAT sensor malfunction.
5. ECM malfunction. A19/
B39 P0103/
P0123/
P0341/
P0342

6E-132 3.5L ENGINE DRIVEABILITY AND EMISSIONS Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure Parts Related
ECM Pin
No. Related
Multiple
DTC
P0117 A Engine Coolant Temperature
Sensor Low Input ECT sensor output voltage is below 0.08V. ECT sensor output voltage is
more than 0.08V. 1. Sensor signal circuit short to ground circuit.
2. ECT sensor malfunction.
3. ECM malfunction. A21 -
14
P0118 A Engine Coolant Temperature
Sensor High Input ECT sensor output voltage is more than 4.8V. The ECM uses default engine
coolant temperature value
based on start-up ECT and
time from start.
ECT sensor output voltage is
below 4.8V. 1. Sensor signal circuit open or short to voltage
circuit.
2. Sensor ground circuit open or short to voltage
circuit.
3. Poor connector connection
4. ECT sensor malfunction.
5. ECM malfunction. A21/
A22 P0406
1. No DTC relating to barometer sensor, ECT
sensor, CMP sensor, CKP sensor, MAF
sensor and TPS (low input & high input).
2. Engine speed is more than 2000rpm.
3. Engine coolant temperature is more than
75
C.
4. TPS output voltage is between 0.24V and
0.26V. Above conditions are met for 3
seconds.
OR
P0121 A Throttle Position Sensor
Range/Performance
1. No DTC relating to barometer sensor, ECT
sensor, CMP sensor, CKP sensor, MAF
sensor and TPS (low input & high input).
2. Engine speed is below 3200rpm.
3. Engine coolant temperature is more than
75
C.
4. TPS output voltage is between 4.54V and
4.56V. Above conditions are met for 3
seconds. No fail-safe function. TPS output voltage is below
0.24V or more than 0.26V.
OR
TPS output voltage is below
4.54V or more than 4.56V. 1. TPS malfunction.
2. Sensor signal circuit short to voltage circuit.
3. Electrical interference.
4. ECM malfunction. B27/
B26/
B39 - P0122 A Throttle Position Sensor Low
Input TPS output voltage is below 0.24V. TPS output voltage is more
than 0.24V. 1. Sensor power supply circuit open or short to
ground circuit.
2. Sensor signal circuit open or short to ground
circuit.
3. Poor connector connection.
4. TPS malfunction.
5. ECM malfunction. B27/
B26 P0336/
P0337
or
P0342
21
P0123 A Throttle Position Sensor High
Input TPS output voltage is more than 4.56V. The ECM uses default throttle
position value based on mass
air flow and engine speed.
TPS output voltage is below
4.56V. 1. Sensor power supply circuit short to voltage
circuit.
2. Sensor signal circuit short to voltage circuit.
3. Sensor ground circuit open or short to voltage
circuit.
4. Poor connector connection.
5. TPS malfunction.
6. ECM malfunction. B27/
B26/
B39 P0103/
P0113/
P0341/
P0342

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-133
Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure Parts Related
ECM Pin
No. Related
Multiple
DTC
P0131 A O2 Sensor Circuit Low Voltage
(Bank 1 Sensor 1) B21/
B22 P0171/
P1171/
P1172 P0151 A O2 Sensor Circuit Low Voltage
(Bank 2 Sensor 1) 1. No DTC relating to ECT sensor, CMP sensor,
CKP sensor, VSS, injector control circuit,
ignition control circuit and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is between 1000rpm and
4000rpm.
3. Engine coolant temperature is between 70
C
and 110
C.
4. Vehicle speed is between 0km/h and
120km/h.
5. Engine load is between 80% and 160%.
6. Throttle position fluctuation is below 0.28V.
7. O2 sensor bank 1 or bank 2 output voltage is
more than 400mV for 50 seconds. "Open Loop" fuel control. O2 sensor bank 1 or bank 2
output voltage is below 400mV
for 50 seconds. 1. Sensor harness open or short to ground
circuit.
2. O2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. ECM malfunction.
B23/
B24 P0174/
P1171/
P1172 P0132 A O2 Sensor Circuit High Voltage
(Bank 1 Sensor 1) B21/
B22 P0172 P0152 A O2 Sensor Circuit High Voltage
(Bank 2 Sensor 1) 1. No DTC relating to ECT sensor, CMP sensor,
CKP sensor, VSS, injector control circuit,
ignition control circuit and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is between 1000rpm and
4000rpm.
3. Engine coolant temperature is between 70
C
and 110
C.
4. Vehicle speed is between 0km/h and
120km/h.
5. Engine load is between 80% and 160%.
6. Throttle position fluctuation is below 0.28V.
7. O2 sensor bank 1 or bank 2 output voltage is
below 600mV for 50 seconds. "Open Loop" fuel control. O2 sensor bank 1 or bank 2
output voltage is more than
600mV for 50 seconds. 1. Sensor harness open or short to ground
circuit.
2. O2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. AC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. EVAP purge solenoid valve malfunction.
9. Ignition system malfunction.
10. Spark plug malfunction.
11. ECM malfunction. B23/
B24 P0175 P0134 A O2 Sensor Circuit No Activity
Detected (Bank 1 Sensor 1) B21/
B22 -
15

P0154 A O2 Sensor Circuit No Activity
Detected (Bank 2 Sensor 1) 1.No DTC relating to MAF sensor, ECT sensor,
CMP sensor, CKP sensor, VSS, injector
control circuit and ignition control circuit.
2. Engine coolant temperature is more than
70
C.
3. Vehicle speed is more than 60km/h.
4. O2 sensor bank 1 or bank 2 output voltage is
between 350mV and 600mV. "Open Loop" fuel control. O2 sensor bank 1 or bank 2
output voltage is below 0.35mV
consecutively.
OR
O2 sensor bank 1 or bank 2
output voltage is more than
600mV consecutively. 1. O2 sensor malfunction.
2. ECM malfunction.
B23/
B24 -

6E-134 3.5L ENGINE DRIVEABILITY AND EMISSIONS Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure Parts Related
ECM Pin
No. Related
Multiple
DTC
P0171 B O2 Sensor System Too Lean
(Bank 1) - -
44
P0174 B O2 Sensor System Too Lean
(Bank 2) 1. No DTC relating to MAF sensor, IAT sensor,
ECT sensor, TPS, CMP sensor, CKP sensor,
VSS, injector control circuit, ignition control
circuit, O2 sensor circuit low voltage & high
voltage (bank 1 & 2) and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is more than 600rpm.
3. Intake air temperature is more than 50
C.
4. Engine coolant temperature is between 35
C
and 120
C.
5. Engine load is more than 20.
6. EVAP purge solenoid valve on-duty is below
100%.
7. Air-fuel ratio correction volume is more than
150% for 20 seconds. No fail-safe function. Air fuel ratio correction volume
is between 50% and 150% for
5 seconds. 1. Sensor harness open or short to ground
circuit.
2. O2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. ECM malfunction.
- -
P0172 B O2 Sensor System Too Rich
(Bank 1) - -
45
P0175 B O2 Sensor System Too Rich
(Bank 2) 1. No DTC relating to MAF sensor, IAT sensor,
ECT sensor, TPS, CMP sensor, CKP sensor,
VSS, injector control circuit, ignition control
circuit, O2 sensor circuit low voltage & high
voltage (bank 1 & 2) and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is more than 600rpm.
3. Intake air temperature is more than 50
C.
4. Engine coolant temperature is between 35
C
and 120
C.
5. Engine load is more than 20.
6. EVAP purge solenoid valve on-duty is below
100%.
7. Air-fuel ratio correction volume is below 50%
for 20 seconds. No fail-safe function. Air fuel ratio correction volume
is between 50% and 150% for
5 seconds. 1. Sensor harness open or short to ground
circuit.
2. O2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. AC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. EVAP purge solenoid valve malfunction.
9. Ignition system malfunction.
10. Spark plug malfunction.
11. ECM malfunction. - -