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:
Other functions
■ Switching between outside air and recirculated air modes
Press .
The mode switches between outside air mode (indicator off) and recirculated air
mode (indicator on) each time is pressed.
■ Defogging the windshield
Defoggers are used to defog the windshield and front side w ...
Wireless remote control
(if equipped)
The keys are equipped with the
following wireless remote control:
Vehicles without a smart key
system
Locks the doors
Unlocks the doors
Opens the windows*1 and
moon roof*1, 2
Opens the trunk
Sounds the alarm
Vehicles with a smart key system
Locks the doors
Unlocks the doors
Opens the ...
Sound quality is bad in all modes (volume is too low)
Wiring diagram
Inspection procedure
1 Adjust sound quality
Adjust the sound quality.
Operate the radio receiver assy to adjust the sound quality.
Standard: malfunction disappear.
2 Compare it with another car of same model
Compare it with another vehicle of the same mo ...