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
The vehicle speed sensor circuit is sent to cruise control ecu assy as a
vehicle speed signal. For each rotation
of the shaft, the vehicle speed sensor sends a signal through the combination
meter assembly to the
cruise control ecu assy (see the following chart). The cruise control ecu assy
...
Circuit description
The throttle pressure that is applied to the primary regulator
valve (which modulates the line pressure) causes the solenoid
valve slt, under electronic control, to precisely and minutely
modulate and generate the line pressure according the extent
of the accelerator pedal depressed or the o ...
Exterior
Doors
Locking/unlocking
Opening/closing the side windows
Locking/unlocking by using the mechanical key*1
Warning messages
Trunk
Opening from inside
Opening from outside
Warning messages
Outside rear view mirrors
Adjusting the mirror angle
Folding the mirrors
Defogging the mirrors*2
...


