P38 key fob help please

ahve tried changing battery/battery cover/buttons with 2 different companies off ebay as covers are mullerred but neither will work with new bits in - yet put old cover back on everything works again?
It seems as though when pushing the buttons the light on the fobs will not work.
It is driving me crazy as following everything to the letter but they just won't send (red light won't come on the fob) - i'm sure i'm doing somrthing small/silly wrong but completely baffled.
Any one help please?

If in doubt take it to landrover authorised dealer i had a similar prob to this when i had mine and they sorted it in a jiffy!

Dose the buttons work fine without the rubber cover on? if so its the covers your buying. could try genuine from the stealers or is there some dirt around the buttons? or try your old battery cover and the new button cover as sometimes the battery cover dose not contact the small tab on the curcuit board.

These parts are really cheap at main stealer.....worth a visit to them to get it sorted. The ebay bits are sold for more than the dealers sell them for (not often that happens, mind you!)

ok many thanks
looks like visit to main dealer b4 i break them