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 assembly
Inspection
1. Inspect coolant
2. Inspect engine oil
3. Inspect battery
4. Inspect air cleaner filter element sub–assy
5. Inspect spark plug
6. Inspect fan and generator v belt
Hint:
you don’t need to check the belt deflection because auto tensioner is adopted.
7. Inspect ignition ti ...
Thermostat
Replacement
1. Remove engine under cover rh
2. Drain coolant
3. Remove fan and generator v belt
4. Remove generator assy
Disconnect the wire clamp from the wire clip on the rectifire
end frame.
remove the rubber cap and nut, and disconnect the alternator
wire.
d ...
Description
When troubleshooting obd ii vehicles, the only difference
from the usual troubleshooting procedure is that you
need to connect the vehicle to the obd ii scan tool complying
with sae j1978 or the hand–held tester, and read
various data output from the vehicle’s ecm.
Obd ii regulation ...