Remote Battery getting exhausted

The situation I experienced was that one fob was draining, but the second fob was not.
Both stored in the same place.
Coat pocket about 20 feet away, inside house.
Phone was the same (Razr flip-phone) and stored 10 feet from coat. On desk between coat and car.
No other new electronics in the home.

 

Store the fobs in a steel tin can of any size/shape. That will isolate any RF.

 

tuna?

 

but with a cover.......

 

Altoids tin.

 

I used to have a problem with other things in my pocket pressing on the key fob buttons and draining the battery. Then I came up with the solution of placing a store loyalty tag and rubber band over the buttons. Problem solved.



Bill the Engineer

 

Interesting, if somewhat disturbing thread.
It's been about 2 years, I've been thinking of changing the battery in my fob, but since this problem manifested after battery replacement, now I'm thinking I'll just wait until it get's visibly worse.

But this is really interesting. Since in both cases, it seems nothing is changed in usage, or location, and the only parameter seems to be that the battery has been changed.

Very interesting. I'll be watching this thread to see what eventually is determined. If any answer is ever found.

 

I have the old fob.
As much as I'd like to do testing of it and find the cause, it'll probably just be tossed in my parts bin.
Too many other projects.

 

were you on the apollo 13 engineering team?

 

MacGyver got all his ideas from me!

Bill the Inventor

 

sure sounds like it. but wait, you said it's happening on both fobs. unlikely at best.

 

Does anybody know anything about the specific radio frequencies that these things operate at? We are constantly bathed in RF energy from all sorts of sources. Could be something like that. The CR1632 battery from any and all manufacturers should be a lithium cell which has a characteristic power curve of providing nominal voltage (3 VDC) right up to exhaustion where it rapidly drops off. The only other thing I can think of would be a short in one (or more) of the momentary contact switches on the top of the printed circuit board contained within. Maybe a good dusting and/or cleaning with a non-conductive electronics cleaner might do something.

 

it just wouldn't make sense for both fobs to do it at the same time after 3-4 years.

 

Sounds like a short of some kind I recently had this on an iPhone due to lint Etc in the charging port. Note that the button battery has small gap that if bridged will short. perhaps try some thin tape over the gap to make sure the battery is not being shorted directly. Otherwise it could be some debris or water damage internally causing the problem. You can try to clean as best possible. I think I fixed the iPhone but only after I pulled the trigger on the upgrade

 

Can you clarify this a bit. I'm not sure what you mean by small gap?

 

a short in both fobs at the same time?

 

i'm wondering if the car could be depleting the fob battery while driving.