Vauxhall Vivaro power steering fault

Last October my power steering pump stopped working. Went to the garage and I've been told that apparently is poor design of the van and where the pump is situated water dripping directly on to the pump also been told that all connections are burnt and needs replacing. Four months later my dashboard was going crazy (flashing like a christmas tree) any possible fault was alarming out. Went back to the same garage and been told that again water damaged the connections on the pump and I need new one. Last week after 3 weeks since my second pump was fitted and almost £1500 later guess what power steering fault came up on the dashboard again...! Can anyone explain to me how's this even possible.