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Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
DTC Confirmation ProcedureNCEC0054CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
PROCEDURE FOR MALFUNCTION ANCEC0054S01With CONSULT-II
1) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 2 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº, EC-
QG-113.
With GST
Follow the procedure ªWith CONSULT-IIº above.
PROCEDURE FOR MALFUNCTION BNCEC0054S02With CONSULT-II
1) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and wait 2 seconds at most.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº, EC-
QG-113.
With GST
Follow the procedure ªWith CONSULT-IIº above.
NEF068A
NEF068A
DTC P0100 MASS AIR FLOW SENSOR (MAFS)QG16I18DE
DTC Confirmation Procedure
EC-111
Page 554 of 2267
Wiring DiagramNCEC0056
YEC063A
DTC P0100 MASS AIR FLOW SENSOR (MAFS)QG16I18DE
Wiring Diagram
EC-112
Page 555 of 2267
Diagnostic ProcedureNCEC0057
1 INSPECTION START
Which malfunction (A, or B) is duplicated?
Malfunction A or B
A©GO TO 3.
B©GO TO 2.
2 CHECK INTAKE SYSTEM
Check the following for connection.
IAir duct
IVacuum hoses
IIntake air passage between air duct to collector
OK or NG
OK©GO TO 3.
NG©Reconnect the parts.
3 RETIGHTEN GROUND SCREWS
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
SEF994W
©GO TO 4.
DTC P0100 MASS AIR FLOW SENSOR (MAFS)QG16I18DE
Diagnostic Procedure
EC-113
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4 CHECK POWER SUPPLY
1. Disconnect mass air flow sensor harness connector.
SEF995W2. Turn ignition switch ªONº.
3. Check voltage between terminals 2, 4 and ground with CONSULT-II or tester.
SEF996WVoltage: Battery voltage
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors E90, F73
IHarness for open or short between ECM relay and mass air flow sensor
IHarness for open or short between mass air flow sensor and ECM
©Repair harness or connectors.
6 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between mass air flow sensor harness connector terminal 3 and ECM terminal 73.
Refer to wiring diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 7.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0100 MASS AIR FLOW SENSOR (MAFS)QG16I18DE
Diagnostic Procedure (Cont'd)
EC-114
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7 CHECK INPUT SIGNAL CIRCUIT
1. Check harness continuity between mass air flow sensor harness connector terminal 5 and ECM terminal 61.
Refer to wiring diagram.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 8.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
8 CHECK MASS AIR FLOW SENSOR
Refer to ªComponent Inspectionº, EC-QG-115.
OK or NG
OK©GO TO 9.
NG©Replace mass air flow sensor.
9 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-QG-102.
©INSPECTION END
Component InspectionNCEC0058MASS AIR FLOW SENSORNCEC0058S011. Turn ignition switch ªONº.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 61 (Mass air flow sen-
sor signal) and ground.
Conditions Voltage V
Ignition switch ªONº (Engine stopped.) Less than 1.2
Idle (Engine is warmed-up to normal operating
temperature.)1.0 - 1.7
2,500 rpm (Engine is warmed-up to normal operat-
ing temperature.)1.7 - 2.1
Idle to about 4,000 rpm* 1.0 - 1.7 to Approx. 4.0
*: Check for linear voltage rise in response to increases to about 4,000 rpm in
engine speed.
4. If the voltage is out of specification, disconnect mass air flow
sensor harness connector and connect it again. Repeat above
check.
5. If NG, remove mass air flow sensor from air duct. Check hot
film for damage or dust.
SEF993W
SEF987W
DTC P0100 MASS AIR FLOW SENSOR (MAFS)QG16I18DE
Diagnostic Procedure (Cont'd)
EC-115
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Component DescriptionNCEC0066The intake air temperature sensor is built into the mass air flow
sensor. The sensor detects intake air temperature and transmits a
signal to the ECM.
The temperature sensing unit uses a thermistor which is sensitive
to the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.
Intake air temperature
ÉC (ÉF)Voltage*
VResistance
kW
20 (68) 3.5 2.2 - 2.6
80 (176) 1.23 0.31 - 0.37
*: These data are reference values and are measured between ECM terminal 64
(Intake air temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.
On Board Diagnosis LogicNCEC0067
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0110
0110An excessively low or high voltage from the sensor is sent
to ECM.IHarness or connectors
(The sensor circuit is open or shorted.)
IIntake air temperature sensor
DTC Confirmation ProcedureNCEC0068NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
With CONSULT-II
1) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 5 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº, EC-
QG-118.
With GST
Follow the procedure ªWith CONSULT-IIº above.
SEF987W
SEF012P
NEF068A
DTC P0110 INTAKE AIR TEMPERATURE SENSORQG16I18DE
Component Description
EC-116
Page 559 of 2267
Wiring DiagramNCEC0069
YEC772
INTAKE AIR
TEMPERATURE
SENSOR: Detectable line for DTC
: Non-detectable line for DTC
ECM
DTC P0110 INTAKE AIR TEMPERATURE SENSORQG16I18DE
Wiring Diagram
EC-117
Page 560 of 2267
Diagnostic Procedure
1 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect intake air temperature sensor (mass air flow sensor) harness connector.
SEF995W3. Turn ignition switch ªONº.
4. Check voltage between terminal 1 and ground with CONSULT-II or tester.
NEF228AVoltage: Approximately 5V
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
IHarness for open or short between ECM and intake air temperature sensor
©Repair harness or connectors.
3 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between intake air temperature sensor (mass air flow sensor) harness connector terminal 3 and ECM termi-
nal 73.
Refer to wiring diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 5.
NG©GO TO 4.
DTC P0110 INTAKE AIR TEMPERATURE SENSORQG16I18DE
Diagnostic Procedure
EC-118