For horn not working,check the horn related fuse.If the fuses are checked ok,then its wiring needs to be checked.
See below the Chevy horn wiring for Impala car model.
This will help.
For more horn related solved problems,the list is as follows :----
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See below the Chevy horn wiring for Impala car model.
This will help.
For more horn related solved problems,the list is as follows :----