I agree with the isolator switch theory. See if you can repeat the fault then just remove and refit the keys only, if the fault has not gone then try the isolator switch if it works after that and you can then operate the tilt etc you have found the culprit. In the scheme of things a new switch is relatively cheap
http://marinestore.co.uk/Merchant2/m...ches-and-boxes
you could also try by passing the isolator switch, if you try this disconnect the battery first the last thing you want is a short circuit
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