Air bag clock spring

Absolutely you are correct, assuming the steering shaft did indeed need to be disconnected. It did not for the parts you listed.

You'll need to contact the dealer to get a price for the clock spring. The time is listed at 1.4 hours times the shop's hourly labor rate.

Given the age of the vehicle, I would suggest to the repair shop that did the work that a used salvage yard clock spring is satisfactory as long as they install it for you. If they admit responsibility and they want to go with a new part from the dealer, that's okay too.
There's a few things working in your favor, again, assuming they really did have to disconnect the steering shaft. The first is all the functions supported by the clock spring failed at the same time. When an old, tired clock spring fails from age, you'll lose one thing first, then another system days or weeks later. Most people notice when the cruise control stops working or the "air bag" light turns on. Few notice when the horn stops working until we need it.

The second thing is every clock spring I've ever seen has a cover that can be removed after a number of very small screws are removed. You can physically look at the wound-up ribbon cable to see how it failed. By turning the disconnected steering shaft one or more revolutions one way too far before reconnecting it, the ribbon cable will unwind too far, then the end will fold over on itself. That only happens when the steering system is turned fully one way as far as it can go. That weakens the connections on the cable, but doesn't break them right away. That can take weeks or months to show up. It has to fold over many times before it is stressed enough to break, and here again, you'll lose one system at a time.

If the steering shaft is reinstalled one or more revolutions in the other direction, the ribbon cable will wind up tight the first time the steering system is turned fully in that direction. That tears the end of the cable and all functions are lost right away. You only need that to happen one time. Evidence of that can be seen by how the cable is torn apart on the end.

This message is for a different model, but it explains what I tried to here. This might make it easier to understand.

Possibly. Every clock spring has a ribbon cable that is just the right length to wind up and unwind enough to handle turning the steering system from full-left to full-right, and little more. That is why the wheels / tires, and steering system must be straight ahead when the new clock spring is installed. By having the steering shaft disconnected, the steering wheel can be rotated endlessly in either direction, and doing so rotates the clock spring. All it takes is one revolution to make the assembly not centered, then there's a fifty percent chance it's going to wind up too tight and tear off on one end, and a fifty percent chance it will unwind too far and fold over on itself. It's that folding over that has to occur a lot of times before the ribbon cable breaks from fatigue, and that is the time one system will fail at a time. Sounds like that is not how yours failed. If it was caused by the recent service, you wouldn't notice a problem for some time.

When the cable winds up too tight, it gets torn off the first time the steering wheel is turned all the way to its stop, (not sure if that's left or right, but that's immaterial at this point). With this type of failure, the end of the cable will be ragged and have a jagged end. Some have tiny rivets attaching the copper circuits and the cable will be torn out of those rivets. If this was a failure due to normal age and wear, you'd likely see a smooth, clean break on one end of the cable, and as I mentioned, one system will fail at a time. There can be over a half dozen separate copper circuits or wires running through that ribbon cable. Two are for the "initiator", aka "squib" that fires the air bag. Two or more are for the cruise control switches, if you have them in the steering wheel. One or two are for the horn, and there can be more if you have a heated steering wheel. It is very uncommon to see all the systems fail at the same time from normal age-related fatigue of the cable. That almost always leads to one system failing today, a different system failing last week, and another one might still work for a few more weeks. It's those kinds of clues we look for when trying to diagnose why something failed.

As you described it, the ribbon cable would have wound up too tight, then got ripped off one end. That will always lead to every system failing at that instant. You'll have no horn, the cruise control won't turn on, and the Air Bag Computer will detect the break in the squib. Knowing there's that defect, the computer will set a diagnostic fault code related to "open squib or initiator in driver's air bag circuit", it will turn on the red warning light to tell you, and it will turn the air bag system off so it will not deploy in a crash. I don't know if a passenger air bag could still be operational. I think once a fault code is set, the entire system is turned off by the computer.

Here's links to some related article you may find of interest:

https://www.2carpros.com/articles/symptoms-of-a-bad-airbag-clock-spring

https://www.2carpros.com/articles/steering-wheel-clock-spring-removal

Also be aware, for demonstration purposes, we can light off an air bag with a 9-volt transistor battery, so it's easy to see that static electricity can do the same thing. If you can feel a shock when you walk across carpet, then touch a door knob, that's at least 3,000 volts. That kind of static charge can even be developed by sliding across the seat fabric. The reason you never hear of a mechanic setting off an air bag accidentally is all connectors in the squib circuit are bright yellow to identify them, and the instant one of them is unplugged, the half of the connector on the air bag side has a pair of gold-plated shorting bars that short the two wires together. That forces them to have the same voltage all the time, meaning no voltage difference that could fire the rocket fuel pellet. You only need to have common sense and an awareness of how those circuits work to make this a safe procedure for a competent do-it-yourselfer, if it comes to that.

It does indeed sound like you're right. The only information that's missing is why they needed to disconnect the steering shaft. Tie rod ends, (inners and outers), ball joints, struts, and anti-sway bar links and bushings can all be replaced individually or in groups. You did mention control arms. There are some car models that require the entire cross member to be lowered to perform some services, and that can include control arm replacement. Many models have the rack and pinion steering gear mounted on the cross member, so the steering shaft would have to be disconnected for that service or to replace that steering gear. That would be legitimate reasons for taking the shaft apart, and that is when the steering wheel could be accidentally rotated one or more turns.

I found the procedure for replacing the driver's side upper control arm. That's shown in these three drawings. Note that in step 3 they do say to disconnect the steering shaft. The black arrow is pointing to the pinch bolt.

Back in the '90s I was the suspension and alignment specialist at a very nice family-owned dealership. At one point we had a minor recall that required disconnecting the steering shaft to gain access to a point that needed lubrication. Standard practice was to run a rubber bungee strap through the steering wheel so it wouldn't rotate in case it got bumped. Then it was just a matter of reconnecting it with no need to observe if the wheels were straight or not. Well, eventually I became complacent. The job only took a few minutes, and I could save some time by overlooking that bungee strap. One day I got called away right after I disconnected the steering shaft. Lunch hour arrived. When I returned, I found the new kid grinning as he was spinning the steering wheel around and around. I sent him straight to the parts department to get a new clock spring, then showed him what damage he had caused by playing in a customer's car. The service manager never yelled at him because they knew he hadn't had the related training or warning, but the point is, ... We took responsibility for our mistake and took care of it right away. Reputable shop owners are not afraid to admit their mistakes and take care of them.

From everything you've provided, I'm pretty sure the mechanic caused the broken clock spring, either accidentally, or something happened that he wasn't aware of. The price you were quoted from the dealer seems kind of high compared to what I'm used to seeing, but some clock springs are relatively expensive. You may get a better quote from an independent repair shop, but the part is still likely to come from the dealer.

If you do a Google search for "2011 Nissan Frontier clock spring", you'll find a whole bunch of them at real good prices. You might consider doing a deal with the original mechanic that you'll buy the part if they install it at no charge. If they don't even agree to that, it's time to find a different repair shop. Most shop owners would jump at the chance to keep you happy if that's all it took.

Please keep us updated on your progress.

We have problems with our legal system too. Half of our politicians are lawyers who make their living by making one person give lots of money to another person, then they take a huge cut for themselves, and as a group, they get to determine how much that cut is. As a result, every manufacturer has to factor in the cost of litigation and settlements into the cost of the products and replacement parts we buy. Clock springs are a perfect example. You can be sure someone will be screaming and waving their hands in the air if they're in a crash and the air bag didn't deploy properly. Air bag parts, steering and suspension parts, and brake system parts could be less expensive if it wasn't for the insurance the manufacturers have to pay for. The good news is for the most part we end up with well-tested, reliable parts, including the inexpensive versions from aftermarket suppliers, so in the long run, we win, but we pay for it.