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:
On–vehicle inspection
1. Inspect front axle hub bearing
remove the front wheel.
separate the front disc brake caliper assy .
remove the front disc.
inspect the bearing backlash.
Using a dial indicator, check the backlash near the
center of the axle hub.
Maximum: 0.05 Mm (0. ...
How to proceed with troubleshooting
Troubleshoot in accordance with the procedure on the following pages.
1 Vehicle brought to workshop
2 Customer problem analysis check and symptom check
Without applicable symptoms, proceed to ”a”.
with applicable symptoms, proceed to ”b”.
3 Symptom simulation
4 Prob ...
Circuit description
Monitor description
The ecm commands gearshift by turning the shift solenoid valves ”on/off”.
When there is an open or short
circuit in any shift solenoid valve circuit, the ecm detects the problem and the
mil comes on. Illuminating
the mil, the ecm performs the fail–safe and turns ...