2004 Mitsubishi TJ Magna electrical problem

A few weeks after purchasing a TJ Magna Station Wagon Advance in 2004 we were at a shopping centre car park and after briefly starting the engine would die and not turn over again. After it happened a few times I realised that if I unlocked the steering column and violently moved the steering wheel up and down that the engine would finally start. The dealer denied any knowledge of any inherent issue with the model and could only recommend changing the battery to solve the problem. The intermittent nature of the fault has made it very difficult to identify the cause. I am concerned that the trick of bumping the steering wheel up and down will one day fail to help the car start and my wife or I will be stuck somewhere with the children in a car that won't start. Have you ever heard of this problem? Does Mitsubishi have any responsibility for this obvious generic fault?