So a friend owns a Nissan 300Z that's about 25 years old or something like that. It all of a sudden won't start, nothing has changed since it was last running when it ran perfectly.

The spark plug isn't sparking so we tested it at a few points to see if there was power, but hes not getting power to the coil. He has a hunch that it's his immobiliser having electrical problems because he noticed that rain somehow ends up in his steering column as hes seen it drip out the pedals before (I suspect some of his windscreen gutters are blocked and so it's running into the ventilation systems). So I'm pretty sure that's how immobilisers work - they stop power to the coil.

We'll check it out tomorrow in the daylight but does anyone want to offer some hints beyond that? The fuses are all in tact.

Thanks in advance for any help.