Warning Light On problems of the 2004 Toyota Tacoma

Takata recall? I have a 2004 Tacoma pre-runner 4dr. V-6. My airbag warning light came on approx. Oct. 2014 (50,000 miles). All that I have read so far is that it might be a broken "spiral cable" within the steering wheel. All airbag problems I've seen are with 2005 & newer vehicles? as of Dec. 2015 (60,k miles),I still have the problem but have not yet visited a dealership to identify the fault.

I purchased a used 2004 Tacoma pick-up truck from an independent dealer and noted the front air bag warning light was illuminated. I finally took it to the Toyota dealer for repair in 2013. They replaced the spiral cable in the steering column which turned the air bag warning light off for a few weeks and then it became illuminated again. I took it back and they worked on it for several hours and said the only remedy is to replace the entire air bag assembly for $1600. I am unsatisfied since there have been several recalls on the Tacoma air bag systems from models 2005 and higher but not this year. How can such a similar problem not be a manufacturing issue? meanwhile I probably do not have proper functioning air bags.