I have a 2002 f350. It will not start,we have changed the glow plugs,alternator and it is now worse. Now it buzzes when trying to start and there is a rattle noise under the hood somewhere by the battery on the passenger side. We have tried to jump start it from our other truck with no sucess.Can anyone help us figure out the problem?

Took the batteries out and charged them. then took them and had them tested. They tested good. Checked the cables and see no corrosion.Matter of fact, that was the first thing we did, thinking that was all it was. But the problem continued to get worse. We do have an evolution chip system that came with the truck when we bought it. We are wondering if that is draining the battery? Not sure, we just had it towed to a shop. Tired of trying to figure this out. Thank you for your help. We will let you know what they found. Hopefully it will not cost alot to diagnose... :/ Took the batteries out and charged them. then took them and had them tested. They tested good. Checked the cables and see no corrosion.Matter of fact, that was the first thing we did, thinking that was all it was. But the problem continued to get worse. We do have an evolution chip system that came with the truck when we bought it. We are wondering if that is draining the battery? Not sure, we just had it towed to a shop. Tired of trying to figure this out. Thank you for your help. We will let you know what they found. Hopefully it will not cost alot to diagnose... :/

I just wanted to update on my truck problem. We took it to a shop and he discovered it was the glow plug relay. Which I never knew there was a relay. Also we have a perfomance chip and for some reason it was not shutting down after we turned the truck off so that was the reason for the battery drain. The glow plug relay was also draining it because it was not heating the glow plugs sufficiently and finally quit working altogether. Thank you for your help. btw, the relay cost 112.00 for the part and to put it in the bill came to 398.92 ouch......well worth the money to get the problem over with. I just wanted to update on my truck problem. We took it to a shop and he discovered it was the glow plug relay. Which I never knew there was a relay. Also we have a perfomance chip and for some reason it was not shutting down after we turned the truck off so that was the reason for the battery drain. The glow plug relay was also draining it because it was not heating the glow plugs sufficiently and finally quit working altogether. Thank you for your help. btw, the relay cost 112.00 for the part and to put it in the bill came to 398.92 ouch......well worth the money to get the problem over with.