That sounds like the same excuse they tried on us - turned off because it wasn't a feature. We told them it was working when we bought the car, so it was a feature. That's when they tried the "no sensors fitted" ploy. The missus then got onto Hyundai head office over east, provided the vin no and chassis no., and they confirmed it had sensors fitted and JH could certainly re activate them! I'd suggest get onto the national customer service manager . Go onto Hyundais website and fill out the complaint form, giving details of vehicle and dealer.