mspswede

Hi,

I see lots of threads troubleshooting this issue and plenty of videos, but my question is:

I have a non-CA E60 key fob with the permanent (soldered) battery which no longers takes a charge. Can I simply transfer the circuit board to a new shell and unsolder the battery so I can use a replaceable 2032 battery?

If there is an existing thread on this, feel free to direct me to it.

Thanks!

donpb

I am not sure how chargeable the CR2032 is. Why not just replace it with a known rechargeable battery?

gman6262

Looks like you need a VL2020 rechargeable battery, they are available on Amazon, and here's a DIY video -

mspswede

Thanks for taking the time to replay - you'll see that I'm looking at converting it to a fob with a *replaceable* 2032 battery rather than the rechargeable VL2020. Just wondering whether anyone has any experience with this.

donpb

VL2020 are on eBay too. Just put the rechargeable one back in and be done with it. The car is supposed to recharge it but that can only happen so many times before it stops charging and then the battery needs to be replaced. CR2032 may not be rechargeable and so while it may work, it probably would not work as long.

seanjordan20

No it will not work for long because the car only knows to charge while the key is in so the 2032 will be taking a charge and probably start leaking due to the charge.

scottalexander

What is the mean time between failure on the VL2020 soldered battery?

For example, is it designed to receive "X" number of charging cycles?

If so, what is X?

seanjordan20

Approximately 1000 charges charging at 3.4v and current 1.4mA per Panasonic. Of course it depends on how much you drive your car.

donpb

Excerpt from VL2020 Datasheet,

• Charge / Discharge cycle of 1000 times at 10% discharge to normal capacity.

scottalexander

Does that mean the CAS module figures out the VL2020 battery is at 90% charge and then kicks in to charge it to 100% (which counts as one of the 1,000 charge cycles)?

If so, now we need to figure out how long (or how many days) the VL2020 can hold a charge before it drops to 90% charged?