I went to start the EB yesterday and received a message to change to Key FOB battery(s). The car is not quite a year old. So, I went to Best Buy this morning and picked up four Lithium Batteries, CR-2025, per the manual.

The FOB's take two of these batteries each. Change instructions are in the manual with photos; however, One thing I noted, the instructions to open the FOB leave out an important note..after breaking the inside of the FOB loose at the bottom, with a coin, do not try and pull this panel out as it is also fastened by two very small snap in clips at the top of the FOB. If you pull up on the panel without releasing these clips, they most likely will break.

Otherwise, very easy service to perform and honestly, not worth a trip to the dealer.

 

When you removed the batteries did you notice a Vaseline like substance on the battery surfaces?

 

Yes, believe it is some sort of electrical grease. helps from rusting, etc. I think I even read somewhere to not remove it when changing batteries

 

No...that is one reason your fob quit working, it is a byproduct of an electrolytic action and it is normal and will kill your battery. Wipe all of the substance off from both the battery and the contacts and you should be good. It is basically the same stuff that collects around your car's battery terminals.

 

I just saw your post, and yes, the Panasonic batteries in the failed FOB did have a very small amount of what appeared to be grease on them. However, the Energizer batteries in the second remote, which was working fine, did not have any substance on them. I went ahead and replaced them with the new Energizer batteries just to be on the safe side.

I always clean the battery contacts before installing them. This is the first FOB I have had fail.

 

Always make sure when checking new batteries to make sure they are not fakes. I bought two key batteries from Amazon last week and half of the 5-pack I got were fakes!

The fob that takes two CR2025 batteries can be a little tricky to change. I made 4 videos showing how to change every Ford Mustang key fob battery in the last 20+ years: https://fobbattery.com/vehicles/ford/mustang/

 

You might know it, I keep 2032's at hand as all my other FOB's use them. Now, I gotta buy a different one just for the wife's car. Dang first world problems.

 

After nearly 42 years I think I'll keep her. Plus, I'm too old to train another.