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:
Terminals of ecu
1. Inspect integration relay
Disconnect the connector and check the continuity of each terminal of
the disconnected connector.
Standard :
If the result is not as specified, the vehicle’s side may malfunction.
Reconnect the connector and check each terminal.
Standard:
If ...
System description
The ecm uses signals from the vehicle speed sensor and crankshaft position
sensor to detect the actual
gear position (1st, 2nd, 3rd or o/d gear).
Then the ecm compares the actual gear with the shift schedule in the ecm memory
to detect the mechanical
trouble of the shift solenoid valves, th ...
Inspection procedure
1 Check operation(stop lamp swtich assy)
Check that the stop light comes on when the brake pedal is depressed,
and turns off when the brake
pedal is released.
2 Input signal check
See input signal check on page 05–745.
check the indicator light when the brake pedal ...