Abstract: Fast and highly sensitive monitoring of electrical resistance-type heating elements of seat heaters in automotive vehicles is achieved by short-time breaking of the power supply to the electrical resistance-type heating element and coupling the electrical resistance-type heating element during this interruption to an electrical measuring section for applying to the electrical resistance-type heating element a measuring current which is significantly lower than the heating current. A controlling and monitoring circuit operating in this way permits testing of the electrical resistance-type heating element for a plurality of types of faults within a wide range of operating conditions.

Abstract: Improved vehicle seats can be made in a process in which the seat-covering material and a flat heater are inserted into a negative mold for a vehicle seat and the mold is filled with in-situ foam because the flat carrier for the heating conductor of the heater is constituted by a braided wide-mesh grid made of plastic strings or plastic yarns, which during the filling of the negative mold for vehicle seats with in-situ plastic foam are surrounded by the foam substantially without a change of the porosity of the plastic foam.