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:
Warning lights
Warning lights inform the driver of malfunctions in the indicated vehicle’s systems.
*1: Vehicles without a smart key system:
These lights turn on when the engine switch is turned to the “ON” position to indicate
that a system check is being performed. They will turn off after the engi ...
Brake Hold
The brake hold system
keeps the brake applied
when the shift lever is in D,
B (vehicles without paddle
shift switches), M (vehicles
with paddle shift switches)
or N with the system on and
the brake pedal has been
depressed to stop the vehicle.
The system releases the
brake when the accelerator
peda ...
Inspection procedure
1 Inspect cruise control actuator assy
Turn the ignition switch to off.
disconnect the cruise control actuator assy connector.
measure the resistance between terminals 1 (mo) and 2
(mc) of cruise control actuator assy.
Hint:
if control plate position is fully opened or ...


