Anyone taken apart a clockspring (contact unit for airbag)? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

elgyqc · 08-09-2021, 02:52 PM

My horn stopped working and I traced it to the ground connection not making it through the clocksping under the steering wheel. I was able to find a used one locally so the Boxster has got its beep back, but I would like to have a look inside the old one to see if it is reparable. I haven't found an easy way to disassemble it so am looking for tips.

I assume the center ring in the picture has to be pushed back through to separate the top and the bottom of the unit.

elgyqc · 08-10-2021, 10:14 AM

I got it apart with minimal damage by prying around the inner ring while pulling on the top part, .
It is not really a spring, just a long coiled ribbon cable with connectors on both ends, so nothing is under tension and it is easy to handle. The problem is that the connectors are sealed so I haven't yet figured out if I can fix the conductor that is non-continuous.

ike84 · 08-10-2021, 12:38 PM

Ive never taken apart the clockspring before, but the HVAC unit uses a 16 channel ribbon cable and the connectors on each end are the self-piercing type. I can't tell from the pics but see if the connector separate from the board and then possible the connector away from the ribbon.

elgyqc · 08-10-2021, 02:30 PM

Finally found the problem was the ground wire was broken at the female spade connector that attaches to the steering wheel. Should have checked that before taking it apart.
While checking the continuity I dropped the unit and the ribbon cable fell out. I was able to get it back in but will have to experiment to make sure it is not too tightly or too loosely wound.
Given that Porsche is asking around $300 US for a new one and used ones are mostly over $100 I consider this a worthwhile repair. I only paid about $65 for the one I found locally but now I will have a spare...

elgyqc · 08-11-2021, 06:00 AM

... and while I'm on the topic, what exactly are the 2 tabs that stick up about an inch at the top and bottom of the front? I surmise that they engage in holes in the steering wheel and turn the top part of the clockspring with the steering wheel These tabs are broken on many clocksprings (including the one I just installed) but it works despite this. It looks to me like the wiring connector which also passes through a hole in the steering wheel takes over this function. Since there is not a lot of pressure involved I don't see that it would be a problem for the wires. Next time I have the clockspring out I will fix these tabs.