Put the fob guts into iPhone case?

BMWCali · 09-03-2012, 01:16 PM

Thinking if there's a way to not have to carry the fob. See, I've managed to do away with every other key. An RFID fob is used to open my front door, as well as the common areas around my apartment complex so I just opened my iPhone and glued that chip to the inside of the back casing. Works like a charm. I just pass my iPhone in front of the sensor and it opens the doors.

Wondering if I might be able to do the same for the BMW fob. Afterall, I'm guessing with Comfort Access that it works using some kind of RFID system. If I could put that in either my iPhone or my iPhone case, then I wouldn't have to carry the fob at all. With Comfort Access, you can lock, unlock and pop the trunk all with the key in your pocket, which I'm guessing is all done via an RFID chip in the fob.

Anyone know how big that chip is and if it can be popped out and will work independently? If so, I can put it either in my iPhone or its case and carry no keys at all.

I don't carry a wallet either... my iPhone case holds 3 credit cards on the back of it and that's my wallet.

So no keys and no wallet... just grab my iPhone and go out the door.

kokopuffs405 · 09-03-2012, 01:33 PM

What a great idea hmmmm

Subscribed

BMWCali · 09-03-2012, 02:25 PM

Anyone have pictures of the inside of a fob? Anyone want to open theirs up and post some pictures? I don't have my car yet, otherwise I'd do it. They should be easy to open and just pop open using a flathead screwdriver since they are expected for a user to open them to replace the battery.

CurlyFatAngry · 09-03-2012, 05:37 PM

First of all you need a power source for the keyfob to work, so sticking on the back of a phone wouldn't work easily unless you get power to it somehow ... maybe sticking the CR battery as well.

The problem is you created a security single point of failure, as someone who designs IT systems for a living I have to advise against this approach. You lose your phone to me I have complete access to your life. Car, apartment, money ... etc. Within hours I can do so much damage it's not worth it. Right now you can remote wipe handheld devices, but until you can do so with those other chips you have stuck on the back my advise is don't do it.

Cyberdemon · 09-03-2012, 07:13 PM

You could absolutely package it together. But in reality, it probably wouldn't save more than a wall thickness of plastic.

There's no way you are going to get those guts inside of your phone, because unlike a passive RFID tag which is paper thin, you have a full functioning radio transmitter inside, and you'll still want access to the keys on the keypad.

Realistically you could probably rapid prototype a housing/case that combined the two, but 3d printed parts are pretty crappy, brittle, and have really poor UV performance so it would probably break after a few months.

BMWrules7 · 09-03-2012, 07:18 PM

Quote:

Originally Posted by BMWCali

Thinking if there's a way to not have to carry the fob. See, I've managed to do away with every other key. An RFID fob is used to open my front door, as well as the common areas around my apartment complex so I just opened my iPhone and glued that chip to the inside of the back casing. Works like a charm. I just pass my iPhone in front of the sensor and it opens the doors.

Wondering if I might be able to do the same for the BMW fob. Afterall, I'm guessing with Comfort Access that it works using some kind of RFID system. If I could put that in either my iPhone or my iPhone case, then I wouldn't have to carry the fob at all. With Comfort Access, you can lock, unlock and pop the trunk all with the key in your pocket, which I'm guessing is all done via an RFID chip in the fob.

Anyone know how big that chip is and if it can be popped out and will work independently? If so, I can put it either in my iPhone or its case and carry no keys at all.

I don't carry a wallet either... my iPhone case holds 3 credit cards on the back of it and that's my wallet.

So no keys and no wallet... just grab my iPhone and go out the door.

I thought about something similar in the past. Redesign the fob do that it is spread out and fits into something shaped and sized like a credit card.

I would forgo the buttons altogether and just go with the transponder so it will work to open doors and start car with comfort access.

So, we take apart the fob and redesign it to be the thickness and size of a credit card. Then slip it into your wallet and forget about it!

chrisny · 09-03-2012, 07:59 PM

Remind me to steal your phone.....

Cyberdemon · 09-03-2012, 08:38 PM

Quote:

Originally Posted by BMWrules7

I thought about something similar in the past. Redesign the fob do that it is spread out and fits into something shaped and sized like a credit card.

I would forgo the buttons altogether and just go with the transponder so it will work to open doors and start car with comfort access.

So, we take apart the fob and redesign it to be the thickness and size of a credit card. Then slip it into your wallet and forget about it!

That's easier said than done.

You might be able to thin it out quite a bit, but you'll always have some type of battery (generally a coin-cell) plus the PCB with whatever components are on it. You'll be limited by whatever the thickest component is on the PCB. You might be able to get away by removing some of the thicker components such as switches by de-soldering them.

If someone wants to pull their key open and take pictures you can see what it actually looks like in there.

BMWCali · 09-04-2012, 12:04 AM

Quote:

Originally Posted by Cyberdemon

You could absolutely package it together. But in reality, it probably wouldn't save more than a wall thickness of plastic.

There's no way you are going to get those guts inside of your phone, because unlike a passive RFID tag which is paper thin, you have a full functioning radio transmitter inside, and you'll still want access to the keys on the keypad.

Realistically you could probably rapid prototype a housing/case that combined the two, but 3d printed parts are pretty crappy, brittle, and have really poor UV performance so it would probably break after a few months.

Don't need access to the buttons. I just would need whatever component allows the Comfort Access system to work.

And I don't care about security. Some folks may loose their phone, but I'm not one of them. I've never lost or misplaced my cell phone a single time in my entire life.

BMWCali · 09-04-2012, 12:06 AM

Quote:

Originally Posted by Cyberdemon

That's easier said than done.

You might be able to thin it out quite a bit, but you'll always have some type of battery (generally a coin-cell) plus the PCB with whatever components are on it. You'll be limited by whatever the thickest component is on the PCB. You might be able to get away by removing some of the thicker components such as switches by de-soldering them.

If someone wants to pull their key open and take pictures you can see what it actually looks like in there.

I could be wrong, but I suspect a battery is only needed for the circuit board that powers the buttons for lock/unlock/alarm, etc. I suspect the RFID chip that works with Comfort Access requires no power source just as a regular RFID chip does not.

I only want the part that makes Comfort Access work. I have no need for the buttons. Yes, I'll only be able to lock and unlock the car when within arms reach, but that's totally fine with me.

ChiefBroady · 09-04-2012, 01:06 AM

Quote:

Originally Posted by BMWCali

I could be wrong, but I suspect a battery is only needed for the circuit board that powers the buttons for lock/unlock/alarm, etc. I suspect the RFID chip that works with Comfort Access requires no power source just as a regular RFID chip does not.

I only want the part that makes Comfort Access work. I have no need for the buttons. Yes, I'll only be able to lock and unlock the car when within arms reach, but that's totally fine with me.

That is something easily tested. Just remove the battery and try. The thing should be user replaceable.

But if I remember the capital in the manual correctly (yes, I read the whole darn thing in my wait time), the car won't open with an empty key fob battery, and you would have to use the metal key to open and place the key fob into the emergency position to start the engine. So it seems the thing needs power after all.

JUSKIDN · 09-04-2012, 01:31 AM

wow great it it works

BMWCali · 09-04-2012, 01:34 AM

Quote:

Originally Posted by ChiefBroady

But if I remember the capital in the manual correctly (yes, I read the whole darn thing in my wait time), the car won't open with an empty key fob battery, and you would have to use the metal key to open and place the key fob into the emergency position to start the engine. So it seems the thing needs power after all.

Did the manual specify this was the case even with a car outfitted with Comfort Access?

Who has a car with Comfort Access and wants to try it and remove the battery from the fob and see if any parts of the Comfort Access still work (door unlock/lock or trunk release by waving foot underneath the bumper)?

ChiefBroady · 09-04-2012, 07:44 AM

Quote:

Originally Posted by BMWCali

Did the manual specify this was the case even with a car outfitted with Comfort Access?

Who has a car with Comfort Access and wants to try it and remove the battery from the fob and see if any parts of the Comfort Access still work (door unlock/lock or trunk release by waving foot underneath the bumper)?

I think so, but I am not really sure at the moment. I don't have the manual with me. I'll try to remember after to check it out with removing the battery. But this will be another few hours - t's 2:42pm in germany and I have to work about another 3.5 hrs).

I'll get back to you when I've tested the battery-less fob with my CA.

ducatiboy72 · 09-04-2012, 08:13 AM

Comfort access does not work without a battery.

Cyberdemon · 09-04-2012, 08:14 AM

AFAIK, most keyfobs are using active RFID tags and not passive tags simply because of the range.

Passive tags (like what you see with NFC in smart phones or your badge that lets you into work) require near contact to be read. Active and semi-passive tags use the battery to increase the broadcast range of the tag.

You can validate that by removing the battery, but make sure that you also discharge any power left on the PCB by hitting the keys on the keypad. Otherwise you'll have enough juice left on the board to work even with the battery out.

If someone wants to take a picture of the PCB (both sides) and post them I can provide better feedback since I don't have a key to rip apart.

Balzz · 09-04-2012, 08:24 AM

I dd that with my condo entrance fob since its passive. I get interesting looks.

BMWCali · 09-04-2012, 11:13 AM

Quote:

Originally Posted by Cyberdemon

AFAIK, most keyfobs are using active RFID tags and not passive tags simply because of the range.

Passive tags (like what you see with NFC in smart phones or your badge that lets you into work) require near contact to be read. Active and semi-passive tags use the battery to increase the broadcast range of the tag.

You can validate that by removing the battery, but make sure that you also discharge any power left on the PCB by hitting the keys on the keypad. Otherwise you'll have enough juice left on the board to work even with the battery out.

If someone wants to take a picture of the PCB (both sides) and post them I can provide better feedback since I don't have a key to rip apart.

Interesting!

So I like the idea about pulling the guts out of the fob and putting them on a credit card sized slate. How many batteries does the fob have? 1 or 2? We could probably use 2 very thin wafer batteries in the credit card design. I think it's possible to do it. Then I could stick that in one of the credit card slots of my iPhone case and no more fob needed.

BMWrules7 · 09-04-2012, 11:48 AM

Guys and gals,

In the interest of furthering science and the fact that I suck at science projects, will each of you FedEx your spare comfort access enabled key fob to me?

In turn, I will gut it and shift the parts around to fit in the size and shape of a credit card.

I figure by my fifth attempt I will have a working prototype. So, I will practice by destroying your keys. Once I have the process down, then I will use my real key!

Thank you for you service to science. PM me and I will send you my address for you to send your keys.

Please remember, you won't get your key back. But, I promise not to steal your cars.

Cyberdemon · 09-04-2012, 11:59 AM

Since I don't have my car yet or a key to pull apart I'd only be able to guess what's on the PCB, which is why if anyone has pictures it'd be easy to say. Moving the battery inline with the PCB (if it isn't already, though most keyfobs use contacts directly on the PCB for reliability) is easy to do, but you're still going to have something that is probably 4-5mm thick, when it's done, since all you'd really be doing is removing the switches and placing the battery inline. The thicker components will all need to stay where they are.

Could probably pack it into one of those plastic mint packages that are meant to fit in a wallet.

Can't say much more without pictures though.

ChiefBroady · 09-04-2012, 11:59 AM

Sadly, I can confirm that the car does not open without a battery in the fob. It uses one single cell btw. So whatever is rigged up, must have a power source.

TheGemini · 09-04-2012, 12:01 PM

Can you open the car with the bmw remote app on the iphone?

09-03-2012, 01:16 PM	#1
BMWCali Expect the Unusual 259 Rep 1,344 Posts Drives: 2018 X6M Join Date: Jun 2007 Location: U.S.A. iTrader: (1)	Put the fob guts into iPhone case? Thinking if there's a way to not have to carry the fob. See, I've managed to do away with every other key. An RFID fob is used to open my front door, as well as the common areas around my apartment complex so I just opened my iPhone and glued that chip to the inside of the back casing. Works like a charm. I just pass my iPhone in front of the sensor and it opens the doors. Wondering if I might be able to do the same for the BMW fob. Afterall, I'm guessing with Comfort Access that it works using some kind of RFID system. If I could put that in either my iPhone or my iPhone case, then I wouldn't have to carry the fob at all. With Comfort Access, you can lock, unlock and pop the trunk all with the key in your pocket, which I'm guessing is all done via an RFID chip in the fob. Anyone know how big that chip is and if it can be popped out and will work independently? If so, I can put it either in my iPhone or its case and carry no keys at all. I don't carry a wallet either... my iPhone case holds 3 credit cards on the back of it and that's my wallet. So no keys and no wallet... just grab my iPhone and go out the door.
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09-03-2012, 01:33 PM	#2
kokopuffs405 Yup 104 Rep 699 Posts Drives: BMW? Join Date: Apr 2010 Location: Maryland iTrader: (10) Garage List 2014 BMW M5 [0.00]	What a great idea hmmmm Subscribed __________________ Oh hello
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09-03-2012, 02:25 PM	#3
BMWCali Expect the Unusual 259 Rep 1,344 Posts Drives: 2018 X6M Join Date: Jun 2007 Location: U.S.A. iTrader: (1)	Anyone have pictures of the inside of a fob? Anyone want to open theirs up and post some pictures? I don't have my car yet, otherwise I'd do it. They should be easy to open and just pop open using a flathead screwdriver since they are expected for a user to open them to replace the battery.
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09-03-2012, 05:37 PM	#4
CurlyFatAngry Lieutenant 18 Rep 509 Posts Drives: his BMW as much as he can ! Join Date: May 2008 Location: Toronto iTrader: (0)	First of all you need a power source for the keyfob to work, so sticking on the back of a phone wouldn't work easily unless you get power to it somehow ... maybe sticking the CR battery as well. The problem is you created a security single point of failure, as someone who designs IT systems for a living I have to advise against this approach. You lose your phone to me I have complete access to your life. Car, apartment, money ... etc. Within hours I can do so much damage it's not worth it. Right now you can remote wipe handheld devices, but until you can do so with those other chips you have stuck on the back my advise is don't do it. __________________ '15 X3 '12 BSM w/ Coral red dakota 328i Sport Line, Premium, 40% tint '11 Deep Sea Blue E92 335i XDrive, M3 spolier, black grille '08 Jet Black E92 328xi, Premium, Sport, iPod, Black Grille, GP Thunder, Painted Reflectors
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09-03-2012, 07:13 PM	#5
Cyberdemon Brigadier General 1538 Rep 3,331 Posts Drives: 2020 X5 40i, 2018 M3 Comp Join Date: Jun 2012 Location: Long Island NY iTrader: (3)	You could absolutely package it together. But in reality, it probably wouldn't save more than a wall thickness of plastic. There's no way you are going to get those guts inside of your phone, because unlike a passive RFID tag which is paper thin, you have a full functioning radio transmitter inside, and you'll still want access to the keys on the keypad. Realistically you could probably rapid prototype a housing/case that combined the two, but 3d printed parts are pretty crappy, brittle, and have really poor UV performance so it would probably break after a few months. __________________ Current: '20 X5, '18 M3 ZCP Previous: '11 E90 335i, '11 E90 M3, '16 VW GTI, '15 M235i, '13 335i, '08 TL-S, '00 Corvette
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09-03-2012, 07:59 PM	#7
chrisny Brigadier General 547 Rep 3,307 Posts Drives: 2020 X5 40i Join Date: Apr 2012 Location: NY iTrader: (0)	Remind me to steal your phone.....
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09-04-2012, 01:31 AM	#12
JUSKIDN Captain 67 Rep 601 Posts Drives: 2013 EBII 328i M Sport Join Date: May 2012 Location: Baton Rouge, LA iTrader: (0)	wow great it it works __________________ It's not illegal. It's frowned upon, like masturbating on an airplane.
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09-04-2012, 08:13 AM	#15
ducatiboy72 Private First Class 15 Rep 109 Posts Drives: F31 M-Sport Join Date: May 2012 Location: Norway iTrader: (0) Garage List 2013 BMW 320ia Tour ... [0.00]	Comfort access does not work without a battery.
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09-04-2012, 08:14 AM	#16
Cyberdemon Brigadier General 1538 Rep 3,331 Posts Drives: 2020 X5 40i, 2018 M3 Comp Join Date: Jun 2012 Location: Long Island NY iTrader: (3)	AFAIK, most keyfobs are using active RFID tags and not passive tags simply because of the range. Passive tags (like what you see with NFC in smart phones or your badge that lets you into work) require near contact to be read. Active and semi-passive tags use the battery to increase the broadcast range of the tag. You can validate that by removing the battery, but make sure that you also discharge any power left on the PCB by hitting the keys on the keypad. Otherwise you'll have enough juice left on the board to work even with the battery out. If someone wants to take a picture of the PCB (both sides) and post them I can provide better feedback since I don't have a key to rip apart. __________________ Current: '20 X5, '18 M3 ZCP Previous: '11 E90 335i, '11 E90 M3, '16 VW GTI, '15 M235i, '13 335i, '08 TL-S, '00 Corvette
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09-04-2012, 08:24 AM	#17
Balzz Captain 96 Rep 958 Posts Drives: F97 X3M Join Date: Mar 2009 Location: Toronto iTrader: (1) Garage List 2019 M4 [0.00] 2021 X3M [0.00]	I dd that with my condo entrance fob since its passive. I get interesting looks.
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09-04-2012, 11:48 AM	#19
BMWrules7 Lieutenant Colonel 350 Rep 1,684 Posts Drives: 2015, 740 LdX, Alpine White Join Date: Mar 2011 Location: Boston Area iTrader: (0)	Guys and gals, In the interest of furthering science and the fact that I suck at science projects, will each of you FedEx your spare comfort access enabled key fob to me? In turn, I will gut it and shift the parts around to fit in the size and shape of a credit card. I figure by my fifth attempt I will have a working prototype. So, I will practice by destroying your keys. Once I have the process down, then I will use my real key! Thank you for you service to science. PM me and I will send you my address for you to send your keys. Please remember, you won't get your key back. But, I promise not to steal your cars.
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09-04-2012, 11:59 AM	#20
Cyberdemon Brigadier General 1538 Rep 3,331 Posts Drives: 2020 X5 40i, 2018 M3 Comp Join Date: Jun 2012 Location: Long Island NY iTrader: (3)	Since I don't have my car yet or a key to pull apart I'd only be able to guess what's on the PCB, which is why if anyone has pictures it'd be easy to say. Moving the battery inline with the PCB (if it isn't already, though most keyfobs use contacts directly on the PCB for reliability) is easy to do, but you're still going to have something that is probably 4-5mm thick, when it's done, since all you'd really be doing is removing the switches and placing the battery inline. The thicker components will all need to stay where they are. Could probably pack it into one of those plastic mint packages that are meant to fit in a wallet. Can't say much more without pictures though. __________________ Current: '20 X5, '18 M3 ZCP Previous: '11 E90 335i, '11 E90 M3, '16 VW GTI, '15 M235i, '13 335i, '08 TL-S, '00 Corvette
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09-04-2012, 11:59 AM	#21
ChiefBroady Private 2 Rep 78 Posts Drives: 2013 328i M sport Join Date: Aug 2012 Location: Germany iTrader: (0)	Sadly, I can confirm that the car does not open without a battery in the fob. It uses one single cell btw. So whatever is rigged up, must have a power source.
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09-04-2012, 12:01 PM	#22
TheGemini Registered 0 Rep 2 Posts Drives: F10 523i Join Date: Jul 2012 Location: The Netherlands iTrader: (0)	Can you open the car with the bmw remote app on the iphone?
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