Citroen C4 won't start

My Citroen C4 has been standing for two weeks and now it will not start. I have charged the battery and it is showing 12 volts, but the electrics will not switch on and the engine refuses to turn over. Any ideas?

Asked on 25 July 2013 by Tony Howe

Answered by Honest John
The fob battery has probably lost its codes, but worth putting another one in just in case it still has the codes but is too weak to transmit them. You have to change the battery within 10 seconds or it loses the codes entirely, so have the new battery ready before you open the fob.
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