1992 eldorado.Original steering wheel works fine. when replaced w/ new used steering wheel,horn sticks and sounds when steering is turned.technician is baffled.I'm out 165.00

I had a new "used" steering wheel (same model)replaced by my Cadillac mechanic.The original was working fine.The leather was a little tattered. The mechanic told me the horn would stick when pushed and also the horn would "sound" when the steering wheel was turned.

The tech spent close to two hrs. working on this.I had no alternative but to leave with the original steering wheel installed.Everything is fine with the original..I'm out 150.00 for the  cost of the steering wheel plus 165.00 I paid to the Cadillac service Dept...Any advice?Please help.