I have seen other answers and questions about this and my specific problem doesn't seem to be answered, basically the gas hob I have won't light completely or it won't light occassionally and in some cases I have to light the gas hob manually on a higher setting as on the lower setting the hob doesn't have a complete ring would this be a gas hob fault or a circuit fault of some kind.
Usually there is just 1 small igniter the gas then jumps to the next jet of Gas until they are all lit. I have seen 2 things cause this. First the openings in the burner can get plugged not allowing enough gas flow. cleaning the burner solves this problem. Second there is usually a small screened mixing port where the gas enters into the burner that draws in air for a proper air fuel ratio. This screen gets clogged with dust, spiders, and even sometimes grease. cleaning the screen or making sure if it is just an opening that spiders have not blocked the air flow path. Both of these problems can be fixed fairly easily. The Gas pressure is very low in the burner so even a flake of rust can stop the flow or a spider web. I find this quite often when remodeling a house that has not been lived in for a few weeks or months.