04 f350 lariat Key fob slowly started not to work until it finally quit. Thought it was the battery but changing it had no change. Do the fobs go bad and need to be replaced?

 

Silly question -- Are you sure the new battery is good?

 

Well I did but it today. I know it couild be bad. just thought of that

 

If your second fob is working, try swapping the batteries with the one that isn't working and see what happens.

 

only have 1 fob

 

I've been going through the same problem with my 2004, fobs worked the started to act up. Bought new batteries then a brand new key fob, about three weeks later new key fob quit. Installed another new battery and no go my buddy is the parts manager so he replaced my three week old fob, worked for a week now today the brand new fob stopped working! I checked the battery and it's good so I tried to synch the fob to the truck and NOTHING I'm 100% convinced it's whatever controls the key for inside the truck is the problem because everything else is brand new

 

Sounds like a key fob to me, I ordered two new key fobs off Amazon for i want to say under $10. It takes longer to unbox it then it does to sync them to your truck. I would say give that a try for a inexpensive "test"

-Last_Stroke

 

I had the same problem with my fob for my van. It worked some days and wouldn't on others. Sometimes I had to press it really hard and stand in a certain place beside of the door. Other days it would work from 20 feet away.

 

I have never had my SD key fob apart but just did my 2005 Buick LaCrosse. There is a membrane that goes between the circuit board and the top cover. This membrane does wear out (and thus exhibits intermittent performance.) On EBay you can find replacement membranes for $10. For Buick you must have replacement fob programmed at dealer or by a locksmith so the membrane is a good deal. The other weak point on a fob is the battery holder. It is glued to the circuit board (via 2 pins) and has one solder connection. If glue comes loose solder connection is easily broken.

 

The FOB I bought off ebay had a cheap battery holder/positive contact, so it wouldn't get powered properly. I could bend the contact so it would work for awhile, but it would fail again after some time. I'm considering soldering in a new, better contact/battery holder.

 

Here is the link to amazon, these have been working everyday for months!

 

Not to high jack but I have two brand new Ford fobs and brand new Duracell batteries and my fobs only work when they want too...I still say it's what's inside the truck that is the problem