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The Cig 12V outlet in the dash by the shifter is powered by the CIG fuse n the under dash fuse block, near the driver's left knee. The same fuse powers the radio, so if the radio works its not the fuse (unless someone rewired the radio)
You said sockets, plural, does that mean that the 12V outlet in the floor console between the seats is also not working? That is powered by the P/POINT fuse in the under dash fuse block.
The overhead DOME light is powered by the DOME fuse, in the under hood fuse block. If not the fuse or the bulb, it could also be the dimmer switch next to the side mirror controls, or perhaps just that dimmer is set to OFF.
Theoretically could be caused by some other issue further upstream, but that would likely also affect other electrical systems as well. If other electrical things aren't working, let us know, that might indicate a common point.