Air Bag Light On problems of the 2007 Lexus RX

My 2007 Rx 350 out of nowhere already 2 years the airbag light for driver is on, I took to the dealer in glendale ( Lexus of glendale) they told me that for diagnosing I have to pay $250 dollars just to tell me what is the problem, and I did 2 years ago, they told me that there is a problem with wiring and needs to be replaced all wiring witch will coat me around $1500 to $1800 dollars, witch I can't pay, and I don't feel safe to drive like that, the coast is that high because they explain to me they need to replace whole wiring that goes somewhere from back to the hood, because it's impossible for them to find witch wire is the problem. In that car I take my family, kid to school, and I feel unsafe to drive, its a safety issue and I think the manufacturer had to be responsible.

1. Transmission unexpectedly completely shut down while driving on the freeway. Car jumped forward and completely stopped on the fast lane. I had to call for towing. Transmission was replaced at mechanic shop. Happen in November 2016 2. Oil shooting from the broken hose close to the engine while driving on the freeway. Stopped car and call for towing. Replacement of hose completed at mechanic shop. Happen in 2014. Reimbursed by manufacturer. 3. Random flashing of air bag lights (driver) without any reason. Looks like some sensor/electrical malfunction. Happening now.

The car start flashing driver air bag lights, I took mechanik it's giving some codes. When we contact the dealer to see what's going on they sayt that manufacture is extendet warranty to 72 monts or 72000 miles, because of defective parts, but my car star having problem when I have 87000 miles. I don't understand if the part defective why not put a recall? its not safe to drive when I know the air bag is not functioning correctly, please follow on this complain.