So, I am not sure what it is, I don't think it is a loose connection, but whenever I go to use my key fob, it doesn't work until I am about 10 feet from the car, and it doesn't always work the first time, I replaced the battery in it (it had two Energizer 2015 batteries) I couldn't find them in the store, so I replaced with an Energizer CR2032 (I believe this is what is used in the newer key fobs) but does anyone have any idea what the problem could be with this?

Thanks

 

Take it apart and clean the schmutz off the gold contact patches where the bottoms of the buttons hit. Takes about 5 minutes. There's nothing to these remotes really. No real moving parts besides the buttons.

Mine got the same way: no range at all. Cleaned it, and it'll now work from house to curb behind a glass storm door.

 

Is the Energizer CR2032 battery a sufficient battery for this fob? It doesn't say anywhere inside the case which battery to use.

 

Mine has x2 2016's. I'm not familiar with the 2015's you mention. Given the naming convention though, 2015's should only be .1 mm thinner than 2016's.

2032 = 3.2mm
2016 = 1.6mm

Are you sure you're seeing 2015's and not 2016's? Not saying you're wrong, or being a wiseguy or anything... just curious.

At any rate... mine has x2 2016 batteries.

 

I thought it was the strangest thing myself. But it said 2015. Do you think it makes any difference if it has two 2016s or over 2032?

 

hmmm... swiped this off some page somewhere:

Thickness (3.2 mm versus 1.6 mm) and energy capacity (225
milliampere hour versus 90 milliampere hour).

x1 2032 will give a little more punch than x2 2016's... no idea knowing if that's out of spec for the fob though. Proceed at your own risk I guess.. maybe someone else'll know for sure. Does the owner's manual say anything? Too lazy to look here.

 

Owners manual suggesting that you do something on your own?! Haha, I believe it suggests going to a jaguar dealership

 

If you get a x1 2032 to work with no ill effects, let the forum know. Just think of the money savings!!

As an aside, I remind my wife all the time after shelling out a wad for a repair on the Jag, that it all evens out in the end because we save sooo much money on only having to buy 1 wiper blade for it every year.

 

It's working just as it did with the other two batteries. Only thing is, the signal is still weak. I haven't experienced any ill effects other than that so far. Been shot 3 weeks.

 

Did you clean the contacts? I've heard that you can also use a #2 lead pencil on the bottoms of the buttons. I guess that replaces worn off graphite. Never tried it.

One kind of unorthodox thing I did for a while though, was I taped a small pebble over one of the buttons because it had collapsed so much through years of use. That provided a better displaced force than digging my thumbnail into it. The tape I used was black friction tape cut to size, and it was really almost unnoticeable. It covered the unlock diagram though.

Once I made a habit of regularly taking apart and cleaning it, I've found the collapsed button works just fine. They make generic replacement exoskeletons - case, buttons - those should fix that issue if you can find one the right size.

Wow, this turned into redneck keyfob butchery 101, didn't it?

 

I got two fobs with my car. Both received new batteries. One works only standen next to the car and then only 3 of 4 buttons function. The other one works perfectly. So one is f**ked the other is fine Maybe the same here...

Oh, 2x2016 batteries!

 

I can't find my second fob right now, but when I do I will give it a try and see.

I am currently using 1x CR2032, and it's working pretty well so far. Cleaned off the contact quick with a pencil eraser (this completely slipped my mind) and at first when I just checked it from my window to the curb it didn't work, had the battery in the wrong way, flipped it, now it's working... Will report back tomorrow and let you guys know just how far away it will work up to now.

After I flipped the battery, pressing the headlamp button did nothing until after I pressed the unlock/lock buttons which worked. I was trying not to press the head lamp button too much, I tend to forget that three presses in three seconds sets off the alarm, to which I wake up the whole neighbourhood at 2am and HAVE to go out and put the key in the ignition.
I also noticed that when you hold the lock button it is supposed to close all the windows if they are down, just like if you use the key to globally lock the car, this has not been working from the fob, but in the morning I will give it a try, and see what happens, this would be very convenient for me, as I always have all the windows open. Haha

 

NO - but it does show to use CR 2016 in the Driver's Handbook:



Two CR 2016 required.

Graham

 

Hi there.. I'm just getting organised myself with a new XJ8 (17 years old new lol) and as always the keyfobs needed new batteries.. a CR2032 will not do the job adequately as it supplies 3V, and the recommended CR2016s are half the thickness and 3V each, two of them giving a 6V supply to the keyfob.

 

Reading this thread, just cleaned both of my keyfobs.
Used the eraser on the contacts, works like a charm.

Increased my range from ~2m to ~12meter (~40ft), even with 1 1/2yr old batteries (2x CR2016).
Easy Peasy ...

 

Yep. Steve's right. When you stack them they're in "series", giving the total volts they have:

3v + 3v = 6v
90ma - amps aren't added together.

If they were sitting side-by-side, you'd have a "parallel" connection.

3v + 3v = 3v - volts aren't added together
90ma + 90ma = 180ma - milliamps are added together

So x1 2032 works, just barely - not enough voltage - it's 225ma are sufficient though.

Does milliampere amount really even matter? Someone smarter than me please help.

 

Let me re-phrase that... Does milliampere amount really even matter, in this miniscule application? 225ma -vs- 180ma - that's the question I'm hoping someone will know to the answer to.

I'm surprised that 1x 2032 3v will even work in this application at all, so the 225ma rating it has must come into play. Right?

 

The keyfob circuit is designed to work at 6V, much the same as most electronics worked at higher voltages years ago.

Two of the correct batteries (3V per battery) give you the required 6V total for the circuit to run normally with a fair range, but the same as your remote controlled toys - if the voltage supplied to the transmitter falls (ie batteries failing) it still works but over a more and more limited distance as the voltage falls.

But please note this does *not* mean that if you power your remote via a car battery strapped to your back you can arm or disarm your alarm from a block away lol

The keyfobs are designed to work with a 6V supply but I dare say will work at much lower voltages just with a more and more reduced range..

 

On batteries at least four years old ...

through a steel firedoor set into a concrete wall,
15 rows away with the rear facing away from the door

is there a prize?

 

How far away can you get, if you hold the fob to your head?