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:
Ecu power source circuit
Circuit description
This circuit provides power to operate the tvip ecu.
Wiring diagram
Inspection procedure
1 Check fuse (ecu–b)
Remove the fuse from the instrument panel j/b.
check the continuity of the fuse.
Standard: continuity
2 Check tvip ecu
Disconnect ...
Turning on light switch does not light up night time
illumination of radio receiver
Wiring diagram
Inspection procedure
1 Inspect radio receiver assy(ill+, ill–)
Check that the voltage between terminals at each condition,
as shown in the chart.
Standard:
Repair or replace harness or connector ...
Precaution
Caution:
the corolla is equipped with srs, which comprises a driver airbag,
front passenger airbag
and side airbag. Failure to carry out service operations in the correct
sequence could cause
the srs to unexpectedly deploy during servicing, possibly leading to a
serious accident. Fu ...


