starter clicking

[Thacker]

having a problem with the clio, its a ph 2 172, just replaced the head and belt and not it wont fire, starter just clicks, checked fuses and immob light goes off, but i noticed the rev counter sits at the first notch, say 500 rpm, dunno if it has always done this and im just noticing it now or if tdc sensor is at fault, the battery is charged and ive tryed a booster on it whilst trying to crank and still the same, cheers for any help