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:
Problem symptoms table
The suspected circuits or parts for each problem symptom are shown in the
table below. Use this table to
troubleshoot the problem when a normal code is displayed in the diagnostic
trouble code chart but the problem
is still occurring. Numbers in the table indicate the order in which the
circ ...
Driving assist systems
To help enhance driving safety and performance, the following systems operate
automatically in response to various driving situations. Be aware, however, that
these systems are supplementary and should not be relied upon too heavily when operating
the vehicle.
◆ ABS (Anti-lock Brake Sys ...
Lubrication system
On–vehicle inspection
1. Check engine oil level
after warming up the engine and then 5 minutes after the engine
stops, oil level should be between
the ”l” and ”f” marks on the oil level gage.
If low, check for leakage and add oil up to the ”f” mark.
Notice:
do not ...


