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CAUTION:
Always drive at a safe speed.
2. Check 1st trip DTC.
With GST
Follow the procedure “With CONSULT-III” above.
Is 1st trip DTC detected? YES >> Go to
EC-133, " Diagnosis Procedure "
NO >> INSPECTION END
Diagnosis Procedure INFOID:0000000004780056YES >> Go to
LU-7, " Inspection " .
NO >> GO TO 2. Component Inspection " .
Is the inspection result normal? YES >> GO TO 3.
NO >> Replace intake valve timing control solenoid valve. Component Inspection " .
Is the inspection result normal? YES >> GO TO 4.
NO >> Replace crankshaft position sensor (POS). Component Inspection " .
Is the inspection result normal? YES >> GO TO 5.
NO >> Replace camshaft position sensor (PHASE).
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YES >> GO TO 6.
NO >> Remove debris and clean the signal plate of camshaft rear end or replace camshaft. YES >> Check timing chain installation. Refer to
EM-49, " Removal and Installation " .
NO >> GO TO 7. Inspection " , “INSPECTION AFTER INSTALATION”.
Is the inspection result normal? YES >> GO TO 8.
NO >> Clean lubrication line. Diagnosis Procedure " .
>> INSPECTION END
Component Inspection INFOID:0000000004780057YES >> GO TO 2.
NO >> Replace intake valve timing control solenoid valve.
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2. Provide 12 V DC between intake valve timing control solenoid
valve terminals 1 and 2, and then interrupt it. Make sure that the
plunger moves as shown in the figure.
CAUTION:
Do not apply 12 V DC continuously for 5 seconds or more.
Doing so may result in damage to the coil in intake valve
timing control solenoid valve.
NOTE:
Always replace O-ring when intake valve timing control
solenoid valve is removed.
Is the inspection result normal? YES >> INSPECTION END
NO >> Replace intake valve timing control solenoid valve.
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YES >> Go to
EC-137, " Diagnosis Procedure " .
NO >> INSPECTION END Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Air fuel ratio (A/F) sensor 1
heater control Air fuel ratio (A/F) sensor 1
heater
Mass air flow sensor Amount of intake air DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0031 Air fuel ratio (A/F) sensor 1
heater control circuit low The current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the A/F sensor 1 heater.) • Harness or connectors
(The A/F sensor 1 heater circuit is
open or shorted.)
• A/F sensor 1 heater
P0032 Air fuel ratio (A/F) sensor 1
heater control circuit high The current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the A/F sensor 1 heater.) • Harness or connectors
(The A/F sensor 1 heater circuit is
shorted.)
• A/F sensor 1 heater
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Wiring Diagram
INFOID:0000000004780559
Diagnosis Procedure INFOID:0000000004780060Ground Inspection " .
Is the inspection result normal? B
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YES >> GO TO 4.
NO >> GO TO 3. YES >> GO TO 5.
NO >> Repair open circuit or short to ground or short to power in harness or connectors. Component Inspection " .
Is the inspection result normal? YES >> GO TO 7.
NO >> GO TO 6.
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>> Repair or replace.
Component Inspection INFOID:0000000004780061YES >> INSPECTION END
NO >> GO TO 2.
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Engine speed Heated oxygen sensor 2 heater
Above 3,600 rpm OFF
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 load ONDTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0037 Heated oxygen sensor 2
heater control circuit low The 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
P0038 Heated oxygen sensor 2
heater control circuit high The 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