Parts location

System diagram

Communication table
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Sliding roof
System descriptionCheck for intermittent problems
Hint:
Inspect the vehicle's ecm using check mode. Intermittent
problems are easier to detect with the intelligent tester when
the ecm is in check mode. In check mode, the ecm uses 1
trip detection logic, which is more sensitive to malfunctions
than normal mode (default), which uses 2 trip detec ...
If you think something is
wrong
If you notice any of the following
symptoms, your
vehicle probably needs
adjustment or repair. Contact
your Toyota dealer as
soon as possible.
Visible symptoms
Fluid leaks under the vehicle
(Water dripping from the air
conditioning after use is normal.)
Flat-looking tires or uneven
tire wear
...
Catalyst system efficiency below threshold (bank 1)
Monitor description
The ecm uses sensors mounted in front of and behind the three-way catalytic
converter (twc) to
monitor its efficiency.
The first sensor, the air-fuel ratio (a/f) sensor, sends pre-catalyst
information to the ecm. The second
sensor, the heated oxygen (ho2) sensor, se ...