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:
Diagnostic trouble code chart
If a dtc is displayed during the dtc check, check the circuit listed in the
table below and proceed to the
page given.
* :● ... Mil light up
...
Replacement
1. Discharge refrigerant from refrigeration system
turn the a/c switch on.
operating the cooler compressor at the engine rpm of approx. 1000
For 5 to 6 min., Circulate the refrigerant
and collect compressor oil remaining in each component into the cooler
compressor as much ...
Mass or volume air flow circuit
Dtc p0100 mass or volume air flow circuit
Dtc p0102 mass or volume air flow circuit
low input
Dtc p0103 mass or volume air flow circuit
high input
Circuit description
The maf (mass air flow) sensor measures the amount of air flowing through the
throttle valve. The ecm
uses this information ...


