MY16 GTI Keyfob battery type

[Hillbilly]

If the raised corner of the cap hooks in your pocket and breaks off it will cost a lot more than the correct battery. They are different for a reason, one being what you have found out.

[DKC]

I have installed a CR2032 and the battery cover is completely flat. In addition my fob sits inside a silicone sleeve for protection all the time so no risk of it catching anything.

Changing battery less frequently is the reason for using the larger capacity one.

[fontana302]

Looks more like 40% increase to me.

[Hillbilly]

Hmm.... been reading the posts above and it begs the question of what is the difference between a 2025 button battery and a 2032 button battery?

Well... As already mentioned they both have the same diameter (20mm) and they both have the same voltage (3V) but the 2032 is 3.2 mm thick -therefore 7 mm thicker than the 2025's 2.5 mm housing.

It's this difference that is important because it means that the 2032 can accommodate more "stuff" internally which results in its greater electrical capacity. And the increased "stuff" that's packed into the battery means that the 2032 is physically heavier @ 3.2 grams versus the 2025's weight of 2.6 grams (not that this is important for the Key-fob application)

The capacity of the two batteries is nominally as follows (according to a couple of data-sheets that I managed to pull from the web):

• 2025 = 150 mAh (on continuous discharge at 20℃ under 15kW load to 2.0V end-voltage)
• 2032 = 210 mAh (on continuous discharge at 20℃ under 15kW load to 2.0V end-voltage)

This means that the 2032 packs an increased 180 mWatts of electrical power, which is 90% increase over then 2025

So, if the 2032 can physically fit into the fob - it will be my choice come time to change the battery,

Don

PS: Of course, the numbers above are only applicable to Brand-name button batteries

210-150 =60 Which is 39.6% difference i would say

[DV52]

Looks more like 40% increase to me.

210-150 =60 Which is 39.6% difference i would say

oops - math was never my strong suit!!!

[Ralfi]

Update: The (Panasonic) 2032 battery hasn't worked out - not even 3 weeks since installing it, I got the 'replace keyfob battery' message in MFD.

Swapped it out for a 2025. See how this goes...

[Hillbilly]

Do you carry the remote around in your pocket with other stuff Have known of things in pockets to get turned on flattening the battery for no reason by being pushed aginst something depressing the button.

Mine arent keyless but the remote in the Passat lasted 5 years and the Polo one is 6 1/2 years old and hasnt been replaced.

Both use the CR2025

[DV52]

Update: The (Panasonic) 2032 battery hasn't worked out - not even 3 weeks since installing it, I got the 'replace keyfob battery' message in MFD.

Swapped it out for a 2025. See how this goes...

Ralfi: I had a PM from a Vortex colleague a few months ago who had a similar problem.

Of course, the underlying problem could be battery drain (as the error message suggests), but it's unlikely (IMO) that replacing the battery will a long term solution (because you are tackling the "effect", not the "cause") - given that you have already tried this before.

Anyhow, the problem for my Vortex colleague was real strange - it seems that the issue was caused by a security camera that he retrofitted to the car and that he had powered by tapping into a particular fuse on the car (piggy-back fuse). When he re-routed the fuse to the position for the power socket - bingo, the problem was solved. Go figure!!!

Now, I'm not suggesting that yours is the same problem, but examples like this show how complex these issues can be - especially where components like the immobiliser coil and the insert in the instrument panel is involved (IMO).

So - just as an easy try - why not see what happens with the second key? does using the second key for a period of time result in the same error?

Also - have you actually checked the voltage in the "supposedly" flat battery?

Don

[Ralfi]

Do you carry the remote around in your pocket with other stuff Have known of things in pockets to get turned on flattening the battery for no reason by being pushed aginst something depressing the button.

Mine arent keyless but the remote in the Passat lasted 5 years and the Polo one is 6 1/2 years old and hasnt been replaced.

Both use the CR2025

Nah the key has its own pocket, & I'm always checking to see if it's (a) there & (b) not having pressure applied to it.

Ralfi: I had a PM from a Vortex colleague a few months ago who had a similar problem.

Of course, the underlying problem could be battery drain (as the error message suggests), but it's unlikely (IMO) that replacing the battery will a long term solution (because you are tackling the "effect", not the "cause") - given that you have already tried this before.

Anyhow, the problem for my Vortex colleague was real strange - it seems that the issue was caused by a security camera that he retrofitted to the car and that he had powered by tapping into a particular fuse on the car (piggy-back fuse). When he re-routed the fuse to the position for the power socket - bingo, the problem was solved. Go figure!!!

Now, I'm not suggesting that yours is the same problem, but examples like this show how complex these issues can be - especially where components like the immobiliser coil and the insert in the instrument panel is involved (IMO).

So - just as an easy try - why not see what happens with the second key? does using the second key for a period of time result in the same error?

Also - have you actually checked the voltage in the "supposedly" flat battery?

Don

Thanks again Don.

Just checked the voltages. Both the 2025 & 2032 had a touch over 3v. The 2032 was slightly higher. Though I'm not sure if this basic test is enough to say it's still in good condition?

I've now put the 2032 into the other keyfob to see how long it lasts.

One thing I've noticed is that the battery cover of this keyfob closes flush with the rest of the case whilst the 2032 is inside. The other keyfob doesn't close as flush even with the thinner 2025 currently inside. This slight rise of the battery cover may or may not have occurred when I inserted the 2035 in there. I don't think so though, as the other keyfob looks fine with the bigger battery inside.

[Ralfi]

The 2032 battery only lasted 6 days in the other keyfob before the replace battery warning popped up.

So that's both keyfobs which don't like the 2032.

In goes the 2025, & hopefully no more warnings for the time being...