Toyota Corolla (E120): Check and replace ecu
Notice
: start an inspection of the connector from the backside of the connector on the wire harness side with the connector connected to the ecu.
When no measurement condition is specified, perform the inspection with the engine stopped and also the ignition switch on.
- First check the ecu ground circuit. If it is faulty, repair it.
If it is normal, the ecu could be faulty. In this case, replace the ecu with one that functions normally and check if the symptoms appear.
- Measure the resistance between the ecu ground
terminal and body ground.
Resistance: 1 Ω or less
- Disconnect the ecu connector, check the ground terminals on the ecu side and wire harness side for bends and check the contact pressure.
Other materials:
Inspection procedure
Hint:
hand–held tester only:
narrowing down the trouble area is possible by performing ”a/f control” active
test (heated oxygen
sensor or other trouble areas can be distinguished).
Perform active test using hand–held tester (a/f control).
Hint:
”a/f control” is the active te ...
Catalyst monitor (o2s type)
Preconditions
The monitor will not run unless:
mil is off.
Engine coolant temperature (ect) is 176°f (80 °C) or greater.
Intake air temperature (iat) is 14°f (–10 °C) or greater.*
Notice:
* 2002 and later my vehicles:
the readiness test can be completed in cold ambient c ...
Oxygen sensor monitor (front and rear o2s system)
Preconditions
The monitor will not run unless:
mil is off
drive pattern
connect the obd ii scan tool to the dlc3 to check monitor status
and preconditions.
Start the engine and allow it to idle for 2 minutes or more.
Drive the vehicle at 25 mph ...