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Operation Manual

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7-21
FUEL INJECTION SYSTEM
Make sure that the engine is completely cool before checking the intake air temperature sensor.
5 Defective coolant temperature sensor. Execute the diagnostic mode (di-
agnostic code No. D06).
Cold engine: Displayed temper-
ature is close to the ambient
temperature.
Displayed value is incorrect → Re-
place.
Set the switch on the FI di-
agnostic tool sub-wire har-
ness to "ON", and then
check the fault code dis-
play.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 6.
6 Malfunction in ECU. Replace the ECU.
Fault code No. 22
Symptom Intake air temperature sensor signal is not received properly.
Fail-safe system Able to start
Able to drive
Diagnostic code No. D05
FI diagnostic tool display -20–100°C
Cold engine: Displayed temperature is close to the ambient temperature.
Warm engine: Displayed temperature is approximately 20°C higher than the ambient tem-
perature.
Checking method Check the temperature in the intake manifold.
Item Item/components and probable cause Check or maintenance job Checking method
1 Check the connection and locking condition of
the intake air temperature sensor coupler.
Disconnect the coupler and check the pins.
(bent or broken terminals and locking condition
of the pins)
Poor connection → Properly con-
nect, repair, or replace.
Set the switch on the FI di-
agnostic tool sub-wire har-
ness to "ON", and then
check the fault code dis-
play.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 2.
Fault code No. 21
Symptom Coolant temperature sensor signal is not received properly.
Fail-safe system Able to start
Able to drive
Diagnostic code No. D06
FI diagnostic tool display -20–150°C
Cold engine: Displayed temperature is close to the ambient temperature.
Warm engine: Displayed temperature is the current coolant temperature.
Checking method Check the coolant temperature.
Item Item/components and probable cause Check or maintenance job Checking method