Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems
Toyota Corolla (E120): How to troubleshoot ecu controlled systems
- General information
- How to proceed with troubleshooting
- Customer problem analysis
- Symptom confirmation and diagnostic trouble code
- Symptom simulation
- Diagnostic trouble code chart
- Problem symptoms table
- Circuit inspection
- Electronic circuit inspection procedure
Other materials:
Inspection procedure
Hint:
hand–held tester only:
narrowing down the trouble area is possible by performing ”a/f control” active
test (heated oxygen
sensor or other trouble areas can be distinguished).
Perform active test using hand–held tester (a/f control).
Hint:
”a/f control” is the active te ...
Wireless remote control/electronic key battery
Replace the battery with a new one if it is depleted.
You will need the following items:
● Flathead screwdriver
● Small flathead screwdriver
● Lithium battery CR2016 (vehicles without a smart key system), or CR2032 (vehicles
with a smart key system)
Replacing the battery
...
Circuit description
In the diagram below, when the engine is cranked, current flows from terminal
st2 of the ignition switch to
the starter relay coil and also current flows to terminal sta of the ecm (sta
signal).
When the sta signal and ne signal are input to the ecm, tr is turned on, current
flows to the c ...


