Service light stuck on - how can I fix it?

My 2010 Vauxhall Astra has a service light issue which only comes on intermittently. The light stays on for an average of 1 minute. The problem is more frequent in the winter and wet weather. I have approached Vauxhall who said that they would need to investigate the issue, they also said they could only read the error if the light is on which is hard to predict. Could you advise what the fault could be?
An electrical connection affected by moisture. Unlikely to be anything to worry about, but no one will be able to trace it unless it leaves a fault code or is actually present. The fact it doesn't leave a fault code is reassuring.
Answered by Honest John on

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