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
1 Inspect transmission wire(sl)
Disconnect the transmission wire connector from the
transaxle.
measure the resistance according to the value(s) in the
table below.
Standard:
2 Check harness and connector(transmission wire – ecm)
Connect the transmission wire c ...
Disabling the TRAC system
If the vehicle gets stuck in mud, dirt or snow, the TRAC system may reduce power
from the engine to the wheels. Pressing
to turn the system off may make it
easier for you to rock the vehicle in order to free it.
To turn the TRAC system off, quickly press and release
.
The “TRAC OFF” ind ...
The ambient temperature does not display
Wiring diagram
Inspection procedure
1 Inspect outer ambient temperature sensor
Remove cooler (ambient temp. Sensor) thermistor.
measure resistance between terminals 1 and 2 of cooler
(ambient temp. Sensor) thermistor connector at each temperature.
Resistance:
at 0 c (0 f) ...