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:
Inspection
1. Charcoal canister assy
Visually check the charcoal canister for cracks or damage.
Inspect the charcoal canister operation.
Plug the vent port with the cap.
While holding the purge port closed, blow air (1.76
Kpa, 18 gf/cm2, 0.26 Psi) into the evap port and
...
Replacement
1. Work for preventing gasoline from spilling out
2. Remove front wheels
3. Remove engine under cover rh
4. Remove engine under cover lh
5. Drain coolant
6. Remove cylinder head cover no.2
Remove the 2 nuts, 2 clips and cylinder head cover.
7. Disconnect radiator hose inlet
&nb ...
Inspection procedure
1 Input signal check
See the input signal check on page 05–745.
check the indicator light when the clutch pedal is depressed.
Ok:
the indicator light goes off when the clutch pedal is
depressed.
2 Inspect terminal voltage(d)
Turn the ignition switch to on.
&n ...