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:
Overhaul
Notice: when installing, coat the parts indicated by the arrow with
power steering fluid or molybdenum disulfide lithium base grease.
1. Precaution
2. Disconnect battery negative terminal
3. Inspect center front wheel
4. Remove horn button assy
5. Remove steering wheel assy
sst 09950–50013 ...
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
useful for determining whether
the vehicle was running or stopped, the engine was warmed up or not, th ...
Inspection procedure
1 Check seat position air bag sensor
Sst 09843–18040
Turn the ignition switch to on, and wait at least for 20 seconds.
clear the dtc stored in memory .
turn the ignition switch to lock, and wait at least for 20
seconds.
turn the ignition switch to on, and wait at ...


