Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / Problem symptoms table
Toyota Corolla (E120): 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 circuits or parts should be checked.
Hint: when the problem is not detected by the diagnostic system even though the problem symptom is present, it may be that the problem is occurring outside the detection range of the diagnostic system.
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 ...
Calling the message sender
Calls can be made to an e-mail/SMS/MMS message sender's phone number.
1 Display the “Message Inbox” screen.
2 Select the desired message.
3 Select .
4 Check that the “Call” screen is displayed.
■ Calling from a number within a message
Calls can be made to a number identified ...
Circuit description
When the ignition switch is turned on, battery positive voltage is applied to
the coilwhich closes the contacts
of the efi main relay (marked: efi) and supplies power to terminal +b of the ecm.
This signal causes current to flow to the coil, closing the contacts of the efi
relay and supplyin ...