？
Could you turn on the light?
Literal
Light [object-を] turn-on humbly-receive not [polite-ません] ?
いただけません？ is a very polite but colloquial-feeling request — the ending rises as a question via intonation. つける here means 'to turn on' (opposite of 消す). A request framed with the very polite ~ていただけません but without か and with rising intonation gives a conversational feel.