Toyota Corolla Repair Manual: Catalyst system efficiency below threshold
Dtc p0420 catalyst system efficiency below threshold (bank 1)
Inspection procedure
Hint:
read freeze frame data using the hand-held tester or the obd ii scan tool.
Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, it is
usefu ...
Circuit description
The ecm compares the two waveforms of the heated oxygen sensors located
before and after the catalyst
to determine whether or not the catalyst performance has deteriorated.
Air–fuel ratio feedba ...
Other materials:
Overhaul
Hint:
overhaul the rh side by the same procedure as the lh side.
1. Remove front wheel
2. Drain brake fluid
Notice:
wash the brake fluid off immediately if it comes into contact with any painted
surface.
3. Remove front disc brake cylinder sub–assy
Remove the union bolt and gasket fr ...
Using the interior lights
Interior lights list
1 Front interior light/personal lights
2 Rear interior light
3 Engine switch light (vehicles with a smart key system)
Front interior light/personal lights
■ Front interior light
► Type A
► Type B
1 Off
2 Door position
3 On
■ Personal li ...
Circuit description
The o/d main switch (transmission control switch) is a momentary type switch.
When pressing the o/d main
switch, the o/d off indicator light lights up and the ecm prohibits shifting
into o/d, and when pressing it
once again, the o/d off indicator light goes off and the ecm allows shifting
in ...