Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / Customer problem analysis
Toyota Corolla (E120): Customer problem analysis
Hint
:
- in troubleshooting, the problem symptoms must be confirmed accurately, meaning that all preconceptions must be set aside in order to make an accurate judgement. To ascertain what the problem symptoms are, it is extremely important to ask the customer about the problem and conditions when it occurred.
- The following 5 items are important points in the problem analysis. Past problems which are thought to be unrelated and the repair history, etc. May also help in some cases. Therefore, as much information as possible should be gathered and its relationship with the problem symptoms should be correctly ascertained for use as reference in troubleshooting. A customer problem analysis table is provided for your use in the diagnostics section for each system.
(Sample) supplemental restraint system check sheet.
Other materials:
Audio unit
1 Bluetooth® connection status
If “BT” is not displayed, the Bluetooth® audio/phone cannot be used.
2 Display
A message, name, number, etc. is displayed.
Lower-case characters and special characters cannot be displayed.
3 Displays the set up menu
4 Selects items such as menu and number
...
Inspection procedure
1 Check p squib circuit(airbag sensor assy center – instrument
panel passenger airbag assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the instrument panel ...
Circuit description
The shift solenoid valve sl is turned ”on” and ”off” by signals from the ecm
in order to control the hydraulic
pressure operation, the lock–up relay valve, which then the controls operation
of the lock–up clutch.
Fail safe function:
if the ecm detects a malfunction, it turns the ...