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)
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Circuit description
When the ignition switch is turned on, battery positive voltage is applied to
the coilwhich closes the contacts
of the efi main relay (marked: efi) and supplies power to terminal +b of the ecm.
This signal causes current to flow to the coil, closing the contacts of the efi
relay and supplyin ...
Circuit description
The p/t squib (lh) circuit consists of the airbag sensor assy center and seat
belt pretensioner (lh).
It causes the srs to deploy when the srs deployment conditions are satisfied.
Dtc b0135/73 is recorded when a short is detected in the p/t squib (lh) circuit.
Wiring diagram
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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 ...