Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Catalyst system efficiency below
threshold
Toyota Corolla (E120): Catalyst system efficiency below threshold
Dtc p0420 catalyst system efficiency below threshold (bank 1)
Other materials:
Engine coolant
The coolant level is satisfactory if it is between the “F” and “L” lines on the
reservoir when the engine is cold.
1 Reservoir cap
2 “F” line
3 “L” line
If the level is on or below the “L” line, add coolant up to the “F” line.
■Coolant selection
Only use “To ...
Things you should know
■ If you notice any symptoms
If you notice any of the following symptoms, refer to the likely cause and the
solution, and re-check.
If the symptom is not resolved by the solution, have the vehicle inspected by
your Toyota dealer.
CAUTION
■When using the rear view monitor system ...
Ecm/pcm processor
Dtc p0606 ecm/pcm processor
Monitor description
The ecm continuously monitors its internal circuits. This self–check insures
that the ecm is functioning properly.
If a malfunction is detected, the ecm will set the appropriate dtc and
illuminate the mil.
The two cpus, main and sub cpu i ...


