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)

Share this page:

Other materials:

Circuit description
When a misfire occurs in the engine, hydrocarbons (hc) enter the exhaust in high concentrations. If this hc concentration is high enough, there could be an increase in exhaust emissions levels. High concentrations of hc passing through the catalyst also cause to temperature of the catalyst to ...

If the vehicle becomes stuck
Carry out the following procedures if the tires spin or the vehicle becomes stuck in mud, dirt or snow: 1 Stop the engine. Set the parking brake and shift the shift lever to P (automatic transmission or continuously variable transmission) or N (manual transmission). 2 Remove the mud, snow or s ...

Inspection procedure
1 Check side squib(rh) circuit(airbag sensor assy center – front seat airbag assy rh) Disconnect the negative (–) terminal cable from the battery, and wait at least for 90 seconds.  disconnect the connectors between the airbag sensor assy center and the front seat airbag assy ...