EC-142
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER
7.CHECK INTERMITTENT INCIDENT
Perform GI-35, "
Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003856518
1.CHECK AIR FUEL RATIO (A/F) SENSOR 1
Check resistance between A/F sensor terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 2.
2.REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
Discard any (A/F) sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
Before installing new (A/F) sensor, clean exhaust system threads using Heated Oxygen Sensor
Thread Cleaner and approved anti-seize lubricant.
>> INSPECTION END
Terminal No. Resistance
3 and 4 1.8 - 2.44 Ω [at 25°C (77°F)]
3 and 1, 2
∞ Ω
(Continuity should not exist)
4 and 1, 2
P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-143
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
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P0037, P0038, P0057, P0058 HO2S2 HEATER
DescriptionINFOID:0000000003856519
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
OPERATION
DTC LogicINFOID:0000000003856520
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 10.5 V and 16 V at
idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-III
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Heated oxygen sensor 2
heater controlHeated oxygen sensor 2 heater
Engine coolant temperature sensor Engine coolant temperature
Mass air flow sensor Amount of intake air
Engine speed Heated oxygen sensor 2 heater
Above 3,600 rpmOFF
Below 3,600 rpm after the following conditions are met.
Engine: After warming up
Keeping the engine speed between 3,500 and 4,000 rpm for 1
minute and at idle for 1 minute under no loadON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0037Heated oxygen sensor 2
heater (bank 1) control
circuit lowThe current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) Harness or connectors
(The heated oxygen sensor 2 heater
circuit is open or shorted.)
Heated oxygen sensor 2 heater
P0038Heated oxygen sensor 2
heater (bank 1) control
circuit highThe current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) Harness or connectors
(The heated oxygen sensor 2 heater
circuit is shorted.)
Heated oxygen sensor 2 heater
P0057Heated oxygen sensor 2
heater (bank 2) control
circuit lowThe current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) Harness or connectors
(The heated oxygen sensor 2 heater
circuit is open or shorted.)
Heated oxygen sensor 2 heater
P0058Heated oxygen sensor 2
heater (bank 2) control
circuit highThe current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) Harness or connectors
(The heated oxygen sensor 2 heater
circuit is shorted.)
Heated oxygen sensor 2 heater
EC-144
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
P0037, P0038, P0057, P0058 HO2S2 HEATER
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Check 1st trip DTC.
With GST
Follow the procedure “With CONSULT-III” above.
Is 1st trip DTC detected?
YES >> Go to EC-144, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000003856521
1.CHECK GROUND CONNECTION
1. Turn ignition switch OFF.
2. Check ground connection E38. Refer to Ground Inspection in GI-37, "
Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace ground connection.
2.CHECK HO2S2 POWER SUPPLY CIRCUIT
1. Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
2. Turn ignition switch ON.
3. Check the voltage between HO2S2 harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
IPDM E/R connector F12
15A fuse (No. 46)
Harness for open or short between heated oxygen sensor 2 and fuse
>> Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK HO2S2 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between HO2S2 harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 5.
DTCHO2S2
Ground Voltage
Bank Connector Terminal
P0037, P0038 1 F70 2
Ground Battery voltage
P0057, P0058 2 F71 2
DTCHO2S2 ECM
Continuity
Bank Connector Terminal Connector Terminal
P0037, P0038 1 F70 3
F713
Existed
P0057, P0058 2 F71 3 17
P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-145
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
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NO >> Repair open circuit, short to ground or short to power in harness or connectors.
5.CHECK HEATED OXYGEN SENSOR 2 HEATER
Refer to EC-145, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 6.
6.REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner and approved anti-seize lubricant.
>> INSPECTION END
7.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003856522
1.CHECK HEATED OXYGEN SENSOR 2 HEATER
Check resistance between HO2S2 terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 2.
2.REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner and approved anti-seize lubricant.
>> INSPECTION END
Terminal No. Resistance
2 and 3 3.4 - 4.4 Ω [at 25°C (77°F)]
1 and 2, 3, 4
∞ Ω
(Continuity should not exist)
4 and 1, 2, 3
P0102, P0103 MAF SENSOR
EC-149
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
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P0102, P0103 MAF SENSOR
DescriptionINFOID:0000000003856532
The mass air flow sensor (1) is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. The mass air flow sensor controls the temperature of the
hot wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The greater air flow, the
greater the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
DTC LogicINFOID:0000000003856533
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
Which DTC is detected?
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0102
1. Start engine and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-150, "Diagnosis Procedure".
NO >> INSPECTION END
3.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0103-I
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-150, "Diagnosis Procedure".
NO >> GO TO 4.
4.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0103-II
1. Start engine and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-150, "Diagnosis Procedure".
PBIA9559J
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0102Mass air flow sensor
circuit low inputAn excessively low voltage from the sensor is sent
to ECM. Harness or connectors
(The sensor circuit is open or shorted.)
Intake air leaks
Mass air flow sensor
P0103Mass air flow sensor
circuit high inputAn excessively high voltage from the sensor is
sent to ECM. Harness or connectors
(The sensor circuit is open or shorted.)
Mass air flow sensor
EC-150
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
P0102, P0103 MAF SENSOR
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000003856534
1.INSPECTION START
Confirm the detected DTC.
Which DTC is detected?
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2.CHECK INTAKE SYSTEM
Check the following for connection.
Air duct
Vacuum hoses
Intake air passage between air duct to intake manifold
Is the inspection result normal?
YES >> GO TO 3.
NO >> Reconnect the parts.
3.CHECK GROUND CONNECTION
1. Turn ignition switch OFF.
2. Check ground connection E38. Refer to Ground Inspection in GI-37, "
Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace ground connection.
4.CHECK MAF SENSOR POWER SUPPLY CIRCUIT
1. Disconnect mass air flow (MAF) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between MAF sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E7, F121
Harness for open or short between mass air flow sensor and ECM
Harness for open or short between mass air flow sensor and IPDM E/R
>> Repair open circuit, short to ground or short to power in harness or connectors.
6.CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between MAF sensor harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
MAF sensor
Ground Voltage
Connector Terminal
F4 5 Ground Battery voltage
MAF sensor ECM
Continuity
Connector Terminal Connector Terminal
F4 4 F8 56 Existed
P0102, P0103 MAF SENSOR
EC-151
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
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Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check the continuity between MAF sensor harness connector and ECM harness connector.
2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
8.CHECK MASS AIR FLOW SENSOR
Refer to EC-151, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 9.
NO >> Replace mass air flow sensor.
9.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003856535
1.CHECK MASS AIR FLOW SENSOR-I
With CONSULT-III
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT-III and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1” and check indication under the following conditions.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
Without CONSULT-III
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check the voltage between ECM harness connector terminals under the following conditions.
MAF sensor ECM
Continuity
Connector Terminal Connector Terminal
F4 3 F8 58 Existed
Monitor item Condition MAS A/F SE-B1 (V)
MAS A/F SE-B1Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operating temperature.) 0.9 - 1.2
2,500 rpm (Engine is warmed-up to normal operating temperature.) 1.6 - 1.9
Idle to about 4,000 rpm 0.9 - 1.2 to Approx. 2.4*
EC-152
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
P0102, P0103 MAF SENSOR
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 2.
2.CHECK FOR THE CAUSE OF UNEVEN AIR FLOW THROUGH MASS AIR FLOW SENSOR
Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
Crushed air ducts
Malfunctioning seal of air cleaner element
Uneven dirt of air cleaner element
Improper specification of intake air system parts
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.CHECK MASS AIR FLOW SENSOR-II
With CONSULT-III
1. Repair or replace malfunctioning part.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT-III and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1” and check indication under the following conditions.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
Without CONSULT-III
1. Repair or replace malfunctioning part.
2. Start engine and warm it up to normal operating temperature.
3. Check the voltage between ECM harness connector terminals under the following conditions.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
Is the inspection result normal?
ECM
Condition Voltage (V)
Connector+–
Terminal Terminal
F858
(MAF sen-
sor signal)56
(Sensor
ground)Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operating temperature.) 0.9 - 1.2
2,500 rpm (Engine is warmed-up to normal operating temperature.) 1.6 - 1.9
Idle to about 4,000 rpm 0.9 - 1.2 to Approx. 2.4*
Monitor item Condition MAS A/F SE-B1 (V)
MAS A/F SE-B1Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operating temperature.) 0.9 - 1.2
2,500 rpm (Engine is warmed-up to normal operating temperature.) 1.6 - 1.9
Idle to about 4,000 rpm 0.9 - 1.2 to Approx. 2.4*
ECM
Condition Voltage (V)
Connector+–
Terminal Terminal
F858
(MAF sen-
sor signal)56
(Sensor
ground)Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operating temperature.) 0.9 - 1.2
2,500 rpm (Engine is warmed-up to normal operating temperature.) 1.6 - 1.9
Idle to about 4,000 rpm 0.9 - 1.2 to Approx. 2.4*