I recently put the battery the wrong way on a ford focus tdci 2006 .. 2l .when I noticed my alternator was not working anymore so I replaced the altonator its now charging but still the charging light is still on I've tested if its charging and it is 2ndly it no has an engine check light and my power steering is no longer working.I checked it on the computer it says lost communication with the power steering module and also its saying lost communication with glow plug circuit but its starting and no glow plug light is on