Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / Problem symptoms table
Toyota Corolla (E120): Problem symptoms table
The suspected circuits or parts for each problem symptom are shown in the table below. Use this table to troubleshoot the problem when a normal code is displayed in the diagnostic trouble code chart but the problem is still occurring. Numbers in the table indicate the order in which the circuits or parts should be checked.
Hint: when the problem is not detected by the diagnostic system even though the problem symptom is present, it may be that the problem is occurring outside the detection range of the diagnostic system.
Other materials:
Engine mechanical
Service data
Torque specification
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Location
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Inspection procedure
1 Check low pitched horn assy
Connect the positive (+) lead from the battery to the terminal
and negative (–) lead to the horn body, and check that
the horn blows.
2 Check relay (marking: horn)
Remove the relay from the engine room j/b.
check the horn relay conti ...