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:
Before driving
Floor mat
Use only floor mats designed specifically for vehicles of the same model and
model year as your vehicle. Fix them securely in place onto the carpet.
1 Insert the retaining hooks (clips) into the floor mat eyelets.
2 Turn the upper knob of each retaining hook (clip) to secure the flo ...
Inspection procedure
1 Inspect parking brake switch circuit
Check for open and short circuit in parking brake switch circuit
2 Inspect brake fluid level warning switch circuit
Check the brake fluid level in reservoir.
check for open and shot circuit in brake fluid level warning
switch circuit
...
Sound quality is bad in all modes (volume is too low)
Wiring diagram
Inspection procedure
1 Adjust sound quality
Adjust the sound quality.
Operate the radio receiver assy to adjust the sound quality.
Standard: malfunction disappear.
2 Compare it with another car of same model
Compare it with another vehicle of the same mo ...


