Diagnosis of several problems?

[Rumel_miah]

Hi all,

i have a focus ST3 MK2 and have multiple problems yet the local garage are unable to diagnose and fix the problem i have!

 

The problem first started 2 months ago, where when switching the car on the fuel pump relay continuously clicks & won't let me start the car. (the odd time it won't start and comes back with fault 'engine malfunction but then drives as normal) This problem is intermittent & i've purchased a fuel pump to put on this weekend.

Last week i had a sign come on  saying key fob battery low, so i replaced the battery for a new one & for a day the key fob wouldn't work, then the following day key fob is working again however still low battery sign on the dash. Iv'e replaced the battery again with another one just in case the battery was a dud however same warning light came on.

The car battery was flat as it was stood for 2 months, however i gave it a full charge for 24 hours & the battery seems to be holding fine, i'm unsure if replacing the pump will solve the issue & what the low battery issue is