Had a good challenge; '01 Boxster S, horn would only work with the key out of the ignition and no obvious faults. Horn should work at all times.
Fuse and relay good, steering wheel push good and continuity good on the primary and secondary circuits but the clockspring showed some resistance, but not what I thought excessive. My default diagnosis when there isn't a clear cause is a wonky ground somewhere, so I pulled the airbag to check and all looked good, see first pic.
Did some more checking of individual connections, bit of web research, and found the culprit; horn push ground wire had mostly failed inside the wire where it met the terminal. Looked completely fine from the outside, but a gentle tug and...see second pic. New flag terminal and all is good.
Oh, and in the middle of this I decided it was the clockspring and purchased a new one, however I decided not to replace it as the terminal fix works and replacement is a bit invasive. I will eventually use it on one of the three though.
Fuse and relay good, steering wheel push good and continuity good on the primary and secondary circuits but the clockspring showed some resistance, but not what I thought excessive. My default diagnosis when there isn't a clear cause is a wonky ground somewhere, so I pulled the airbag to check and all looked good, see first pic.
Did some more checking of individual connections, bit of web research, and found the culprit; horn push ground wire had mostly failed inside the wire where it met the terminal. Looked completely fine from the outside, but a gentle tug and...see second pic. New flag terminal and all is good.
Oh, and in the middle of this I decided it was the clockspring and purchased a new one, however I decided not to replace it as the terminal fix works and replacement is a bit invasive. I will eventually use it on one of the three though.