Cyearian

i was having issues with my truck a few months ago, started out as having to put my truck in (N) to change speeds of wipers while driving, then had to jump battery every morning, sometimes it would be fine over night but if i went into a store for 15 mins it was dead but as soon as i put cables to it it started right up, then heard a crackling and fizzing under dash but no heat or sparks or anything melted, then dash lights would go crazy with no key in ignition. eventually the truck wouldnt even turn over cables on it or not. was told it was the gem on back of fusebox. ordered one replaced it and now it wont even turn over. put cables on it, charged battery, the theft light comes on and stays solid. when i turn the key over the gauges dont move if no cables on it. then the fuel pump relay starts clicking and wont stop. it was also doing this before i changed the gem module. would changing the gem cause the theft system to take effect? pretty much and the end with my truck. if anyone has any ideas please let me know. would really like to get it fixed. oh its a 2000 f150 XL