gmcjetpilot
Veteran Member
HOW LONG DID YOUR KEY FOB BATTERY LAST?
WHY DID YOU REPLACE IT? WAS IT GETTING FLAKY?
WHAT VOLTAGE WAS YOUR OLD BATTERY WHEN YOU REPLACED IT?
The CR2032 is pretty cheap I know. I just ordered some more, but just
curious how long your battery last and how to test. Here is my opinion.
I never really tracked it, forget when I change battery, but I'd estimate
two years using every day? I am going to replace them based on calendar
spec... say 24 months. When they start to go, operation gets inconsistent.
Just like a "12 volt" car battery is 12.6 volts open voltage (no load), these
little lithium ion batteries also have higher volts than their "3.0 volt" label.
New Battery
I got a pack of NEW CR's and they measured 3.37V. They hold 3.17Vwith
a 100 ohm load. After load test they recovered to 3.26V.
Used Battery
My used batteries measure 3.10 volts (no load with a volt meter). They
suck down to 2.8 volt or less with 100 ohm load. They still worked, but
range is degraded and on occasion nothing happens, even close.
Estimate of Life
I suspect depending on how much you use it, 2-4 years is reasonable.
It may work after 4 years, of everyday use, but put a new battery in.
You will see a difference. Installing a new battery the range and operation
are noticeably better.
100ohm Test
My 100ohm load test is severe, because the norma load is not constant,
there is a pulse coming out of the transmitter, not constant carrier. I came
upwith 100 ohm based on FCC rules, max transmitter power is limited to
100mW or 250 meter (820 feet) range (I recall), which ever one is limiting.
Since the antenna in the key fob is pretty small we are power limited and
range is will under 820 feet. Power may be well under 100mW as well
just because the fob is made to work at close range. However using 100mW
that is abut 0.03 amps (30mV) at 3 volts. That is way more than an electronic
or clock memory. In my opinion if it sucks down below 2.9V or 2.8V it is
tired and spent for FOB use. It will still work as memory stay alive or small
calculator..
Conclusion
If it reads less than 3.2 volts, it is not 100%. When you get a
new one as I say they are 3.26-3.36 volts. Once they get down to 3.1 volts
they are pretty low and your FOB range is less. I suggest changing sooner
than later. The gents below bragging how long they are milking their battery
may be fine, but I am sure their range is limited.
DEALS
I bought 5 Sony for $2.00, $0.40/each and 5 Generic for $0.75, or $0.15/each.
Sony, Eveready, Panasonic or Duracell are better I assume then generic, but
eBay you don't know what you are getting. It could be bootleg. Buying locally
they are more expensive. Also the same factory may make name brands, and
at night make generics and just change the markings and packaging.
INCREASE RANGE
FYI it has been shown if you hold the FOB up to your jaw or temple, skull,
it acts as an antenna and your key FOB range is extended.... not sure what
that does to your brain.. ha ha.
https://www.youtube.com/watch?v=0Uqf71muwWc
https://www.youtube.com/watch?v=_jACSPipPSE
NOTE
Warning if you unlock it too far from the car and keep pushing the FOB you
can de-couple it from the car... (according to owner manual). Also unlocking
times out and it will re-lock if you take too long to get to car and open door.
WHY DID YOU REPLACE IT? WAS IT GETTING FLAKY?
WHAT VOLTAGE WAS YOUR OLD BATTERY WHEN YOU REPLACED IT?
The CR2032 is pretty cheap I know. I just ordered some more, but just
curious how long your battery last and how to test. Here is my opinion.
I never really tracked it, forget when I change battery, but I'd estimate
two years using every day? I am going to replace them based on calendar
spec... say 24 months. When they start to go, operation gets inconsistent.
Just like a "12 volt" car battery is 12.6 volts open voltage (no load), these
little lithium ion batteries also have higher volts than their "3.0 volt" label.
New Battery
I got a pack of NEW CR's and they measured 3.37V. They hold 3.17Vwith
a 100 ohm load. After load test they recovered to 3.26V.
Used Battery
My used batteries measure 3.10 volts (no load with a volt meter). They
suck down to 2.8 volt or less with 100 ohm load. They still worked, but
range is degraded and on occasion nothing happens, even close.
Estimate of Life
I suspect depending on how much you use it, 2-4 years is reasonable.
It may work after 4 years, of everyday use, but put a new battery in.
You will see a difference. Installing a new battery the range and operation
are noticeably better.
100ohm Test
My 100ohm load test is severe, because the norma load is not constant,
there is a pulse coming out of the transmitter, not constant carrier. I came
upwith 100 ohm based on FCC rules, max transmitter power is limited to
100mW or 250 meter (820 feet) range (I recall), which ever one is limiting.
Since the antenna in the key fob is pretty small we are power limited and
range is will under 820 feet. Power may be well under 100mW as well
just because the fob is made to work at close range. However using 100mW
that is abut 0.03 amps (30mV) at 3 volts. That is way more than an electronic
or clock memory. In my opinion if it sucks down below 2.9V or 2.8V it is
tired and spent for FOB use. It will still work as memory stay alive or small
calculator..
Conclusion
If it reads less than 3.2 volts, it is not 100%. When you get a
new one as I say they are 3.26-3.36 volts. Once they get down to 3.1 volts
they are pretty low and your FOB range is less. I suggest changing sooner
than later. The gents below bragging how long they are milking their battery
may be fine, but I am sure their range is limited.
DEALS
I bought 5 Sony for $2.00, $0.40/each and 5 Generic for $0.75, or $0.15/each.
Sony, Eveready, Panasonic or Duracell are better I assume then generic, but
eBay you don't know what you are getting. It could be bootleg. Buying locally
they are more expensive. Also the same factory may make name brands, and
at night make generics and just change the markings and packaging.
INCREASE RANGE
FYI it has been shown if you hold the FOB up to your jaw or temple, skull,
it acts as an antenna and your key FOB range is extended.... not sure what
that does to your brain.. ha ha.
https://www.youtube.com/watch?v=0Uqf71muwWc
https://www.youtube.com/watch?v=_jACSPipPSE
NOTE
Warning if you unlock it too far from the car and keep pushing the FOB you
can de-couple it from the car... (according to owner manual). Also unlocking
times out and it will re-lock if you take too long to get to car and open door.
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