I have read that a common source of an intermittent no start issue is corroded connections at the starter. However on my T5 C70 the starter is below the air box, which seems to require raising the engine to remove. Is there ANY other way of cleaning the connections at the starter?

Even if you take the air box out, you wouldn't be able to 'see' the starter. It is under the intake manifold. You might get easier access from under the car, so long as the splash guard is not in the way.

But, I would check that the battery terminals are not loose or corroded first. Are there any other symptoms of this non start? Are the dash warning lights coming on every time? Do you have a start button?

The newer cars have an interesting start sequence as the computers all talk to each other before engaging the starter - holding the key in the start position has no additional effect. Stupid computers!
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