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:
Floor shift cable transmission control
shift (atm)
Replacement
1. Precaution
2. Disconnect battery negative terminal
3. Remove parking brake hole cover sub–assy
4. Remove console panel upper
5. Remove console box carpet
6. Remove console box sub–assy rear
7. Remove air bag sensor assy center
8. Disconnect oxygen sensor connector
...
Fail–safe chart
If any of the following codes is recorded, the ecm enters the fail–safe mode.
Check for intermittent problems
Hand–held tester only:
by putting the vehicle’s ecm in the check mode, the 1 trip detection logic is
possible instead of the
2 trip detection logic, and the sensitivity to de ...
Circuit description
The actuator motor is operated by signals from the cruise control ecu assy.
Acceleration and deceleration
signals are transmitted by changes in the duty ratio (see below).
Duty ratio:
the duty ratio is the ratio of the period of continuity in one cycle. For
example, if a is the period of co ...