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:
Circuit description
When the idle switch is turned on, a signal is sent to the cruise control ecu
assy. The cruise control ecu
assy uses this signal to correct the discrepancy between the throttle valve
position and the actuator position
sensor values to enable accurate cruise control at the set speed. If the idl ...
Overhaul
1. Precaution
2. Disconnect battery negative terminal
3. Inspect place front wheels facing straight ahead
4. Remove horn button assy
Notice:
if the airbag connector is disconnected with the ignition
switch being at on, dtcs will be recorded.
using a torx socket wrench, loosen the ...
Oxygen sensor monitor (front and rear o2s system)
Preconditions
The monitor will not run unless:
mil is off
drive pattern
connect the obd ii scan tool to the dlc3 to check monitor status
and preconditions.
Start the engine and allow it to idle for 2 minutes or more.
Drive the vehicle at 25 mph ...


