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:
Selecting wheel set (vehicles
with a tire pressure
warning system)
Your vehicle is equipped with a
tire pressure warning system
with a function to register two
sets of ID codes. This allows for
registration of a second wheel
set, for example a winter set.
The wheel set can be changed
only if a second wheel set has
been registered to the system. If
a second wheel s ...
Malfunction in clock
Wiring diagram
Inspection procedure
1 Inspect fuse
Check the continuity in cig fuse.
check the continuity in dome fuse.
2 Inspect harness or connector
Check voltage.
Remove the clock assy with connector still connected.
Measure voltage between ter ...
On–vehicle inspection
1. Inspect turn signal flasher relay circuit
Disconnect the connector from the turn signal flasher
relay and inspect the connector on wire harness side as
shown in the chart.
Standard:
Connect the connector to the turn signal flasher and inspect
the wire harness side connector ...


