when I'm more than 5 feet away from my car the key won't work to unlock the doors or trunk. I've put new batteries in it but still doesn't work. What else can I try?

 

try polishing/cleaning the little red lens on the tip of the key; sometimes that gets dirty and it wont even start the car.
It is made out of the same material as a music CD, so if you're good at cleaning or rubbing scratches out of CDs, you have it made.

Also not all batteries arecretaed equal. I have tried severaltop brandbatteries in mine over the years, and the only ones that truly work well are the panasonic or toshiba that you can buy specifically for keys.

Blue