Old Car - Start Button Conversion??

[wrs 120]

My E36 ignition barrel just died (turns but nothing happens). It initially went to ACC, then RUN, but I felt it crack as I turned it to START and nothing happened. After turning it back off the key then did nothing, just spins in the barrel and the steering lock was on.

Had to drill out the steering lock spring and take the ignition switch block off the back of where the barrel sits so I can start it with a screwdriver.

 

I'm now wondering what the best path forward is to fix/replace. Do I get a new coded barrel from BMW (I assume this is possible) or modify things to go keyless/wireless with a start button...

I quite like the key-less method but want to preserve some sort of security which essentially requires an electronic key, either nearfield or proximity.

Not sure if this has been done/discussed before but I couldn't find the right search words to show anything so here goes:

For the key-less option I'm thinking of the following.

Security

1. Use a Nearfield RFID device plugged into a hole/slot on the dashboard.

2. Use a proximity RF security device like many modern card so you can keep your key in your pocket (likely my preferred).

3. Keypad with pin code.

Either of these enables the electronics that start the car.

Then there's two modes the system could operate in; Auto ACC and non Auto ACC - a switch on the dash will select between the modes.

Non Auto ACC Mode:

1. The electronics get enabled by the security device.

2. Press the Start/Stop Button once - ACC position activated.

3. Press the Start/Stop Button a second time - the RUN position is activated

4. Hold the Start/Stop Button for 2s, engine cranks, internal engine running signal activated.

5. Hold the Start/Stop button for 2s, switch off RUN and ACC if the internal engine running signal is active.

Auto ACC Mode:

1. The electronics get enabled by the security device and the ACC position is immediately activated.

2. Press the Start/Stop Button once - the RUN position is activated

3. Hold the Start/Stop Button for 2s, engine cranks, internal engine running signal activated.

4. Hold the Start/Stop button for 2s, switch off RUN and ACC if the internal engine running signal is active.

 

The issue I'm having is trying to find a Nearfield or Proximity system with a simple relay type contact output that will create the enable signal to allow the engine to be started. Has anyone come across either type of system that could be applied to a car? Maybe a suggestion of donor cars to get a security system from? Have hear a Toyota Ractis might have a suitable system.

Is there any interest in this type of system from anybody - happy to make this system into a kitset that can be retrofitted to any car.

Also, does anyone know ballpark pricing to replace the key/barrel coded to my original? Mine failed after 17:00 on Friday so I could call BMW to get a price...

Edited January 21, 2022 by wrs

[jon dee 500]

[wrs 120]

A little more investigation has found the problem - the barrel is perfectly fine and still works. I've extracted the barrel and found the interfacing system consisting of a muck-metal cast rod/cam/flange that connects between the ignition switch block and key barrel has sheared in half at the narrowest point. Replacing this might be possible by getting bits from the wreckers but I suspect it's a weak point that could fail again any time and old donor parts will probably have a limited life.

Have decided not to bother trying to fix this and will go down the engine start/stop button route. Now to find a security device. I already have remote lock/unlocking as part of the alarm system so just need a discrete security fob type device to replace the key to enable starting.

By drilling out the spring that pushes up the steering lock mechanism the steering wheel is free. However, I've noticed the small sheet metal activator thingy that locks the steering is very free and slides up super easy when pushed with a long screwdriver. I'm a little uncomfortable relying on gravity to keep this activator inactive and will glue it down so it can never lock the steering. It would be disastrous to have this activate mid corner on a big bump - probably unlikely but better to be safe than potentially dead.

Now, to find a suitable donor vehicle for a security enable system and figure out how to transfer the electronics... Fabricating a PCB with the logic sequencing for ACC, RUN and START is the easy part.

 

[Sammo 2550]

Not sure if it would suit your application but Autowatch (Good) and Mongoose (Cheap)  have Transponder immobiliser systems designed specifically for automotive use.

Not sure how going keyless would work to unlock the door - could just get an aftermarket immobiliser / alarm and use the fob to unlock the car and disarm the immobiliser then button to start?

Transponder immobiliser only:

http://www.autowatch.co.nz/Vehicle+Security+Products/Car+Alarms++Immobilisers/573PPI+Transponder+Immobiliser.html

Immobiliser with remote unlocking:

http://www.autowatch.co.nz/Vehicle+Security+Products/Car+Alarms++Immobilisers/446Ri+Remote+Immobiliser.html

Not sure how insurers look at this kind of thing?

[wrs 120]

4 hours ago, wrs said:

I already have remote lock/unlocking as part of the alarm system so just need a discrete security fob type device to replace the key to enable starting.

Thanks but already have this sorted. Just need a security coded nearfield/proximity unit with a digital output.

[tawa 150]

I have a bunch of bits sitting on my electronics work bench, plan is to do pretty much the same on my bikes and e36 as well.

They're PN532 breakout boards and Arduiny Nano's, works with common passive tags, just reads the Tag ID, that can be used for the security part. The Nano can be programmed for whatever digital outputs are required. My plan was to have it in the drivers door as well, and run different tags to open and lock it, similarly for the ignition one tag to start and one to turn it off (figured I'd tap into the brake and clutch sensors, ie, if clutch is in it runs the starter, if brake or clutch it turns on the ignition, if none it just turns ACC on).

Anyway, keen to collab on this if you want to do the electronics... I can send you some hardware and tags with an example program if it is what you're after?

[wrs 120]

Thanks, already have a PN532 kit left over from some old projects and had discounted using because it's way too big and too power hungry. The fobs aren't very pretty either. Was hoping to find something good looking in-line with BMW styling. Arduino stuff can be a bit flaky too and libraries often need to be modified to work properly. I only briefly flirted with the PN532 kit - got it working ok but didn't test it in anger for stability or functionality.

My preference is also for a proximity type key similar to what's used in fairly new cars (the type you keep in your pocket).

However, happy to collaborate or do all the work and you can piggy-back off what I do. In my case I need something fairly urgently so I can replace the screwdriver with a proper solution.

Do you have any specific needs?

 

After starting to design the logic for sequencing the start/stop button functionality I've revised the original as I've found a minor improvement:

Security

1. Use a Nearfield RFID device plugged into a hole/slot on the dashboard.

2. Use a proximity RF security device like many modern card so you can keep your key in your pocket (likely my preferred).

3. Keypad with pin code.

Either of these enables the electronics that start the car.

Then there's two modes the system could operate in; Auto ACC and non Auto ACC - a switch on the dash will select between the modes.

Non Auto ACC Mode:

1. The electronics get enabled by the security device.

2. Press the Start/Stop Button once - ACC position activated.

3. Press the Start/Stop Button a second time - the RUN position is activated, hold for 2 seconds more to start, skip step 4.

4. Hold the Start/Stop Button for 2s, engine cranks, internal engine running signal activated.

5. Hold the Start/Stop button for 2s, switch off RUN and ACC if the internal engine running signal is active.

Now only 2 presses to start.

Auto ACC Mode:

1. The electronics get enabled by the security device and the ACC position is immediately activated.

2. Press the Start/Stop Button once - the RUN position is activated, hold for 2 seconds more to start, skip step 3.

3. Hold the Start/Stop Button for 2s, engine cranks, internal engine running signal activated.

4. Hold the Start/Stop button for 2s, switch off RUN and ACC if the internal engine running signal is active.

Now only one press to start.

[tawa 150]

I haven't found the arduino gear too bad for simple stuff, probably be more trusting of that than my coding and wiring and put a bypass in just in case!

Yeh I can see how the prox stuff would be preferable, I have it in my X5 but I wouldn't recommend that particular system it as it is more complicated and expensive than most. Haven't had any experience with modules etc.

For the Prox stuff, my X5 does it all with just one button and it seems to work really well.

• Door handles have a switch on open (pull handle to unlock it, then again to open) and a cap button to push to lock them.
• One push to start car if you have a foot on the brake
• If foot not on brake, one push to turn on ACC, second to turn on IGN
• Turn off requires two presses, one to turn the engine off and another to turn off car - this is probably the one I'd change to just turn everything off

I think for my projects I'd like the ACC and IGN outputs, along with a general purpose one to run a small motor to open a door, for inputs it'd be the switch/button and brake/clutch pedals, and maybe one more for a mode switch.

[dirtydoogle 383]

I probably have an ignition barrel and key you can have, if that's an easier alternative 

[wrs 120]

Thanks but mine is ok - it's the inner mechanism that's broken (see above) and it looks like the broken bits can't be replaced easily. Everyone I've talked to says the whole mechanism needs to be replaced which means breaking the shear bolts. Not keep on this - possibly quite expensive to go new and second-hand parts probably won't have decent life.

Today I hack-sawed the bottom of the steering lock area off and extracted the bits that the spring pushes up to lock the steering wheel. Now there's no possibility of it ever engaging while driving. The key area is now a completely hollow tube.

I've also discovered another set of switch contacts on the ignition block that create a fused 12V supply for the park light system when everything else is off. So I need to add another relay to cater for this switch.

I was going to try to implement the system using discrete logic but have now decided to use a low-power ARM chip instead. It needs 25mA @ 3.3V which equates to about 9mA draw from the battery. That's probably only a little more than the self-discharge rate of the battery and won't be a problem unless the car is parked up for 4 months+.

I'm also flipping and flopping between a proximity key and pin keypad and can't decide yet which way to go. Using a pin means I'll have to give the pin to people for servicing the car. If using an ARM uP I can always create a service pin which can be enabled and disabled as required so my pin is something only I know.

 

[tawa 150]

ARM seems fairly overkill for this sort of thing? I'd expect a keypad to get very tedious very quickly, I'd prefer a normal key over a keypad...

 

[wrs 120]

Yes, way overkill but it's now my minimum platform for anything. I'd likely use a Teensy 4.0 under-clocked from 600MHz down to 24-40MHz with core undervolt as well. The Teensy 3.6/4.0/4.1 are my small platform devices now with the Xylinx Zynq 7020 / 7100 being my usual.

Would be possible to have multiple configuration options with hardware jumper selecting...

[polley 916]

Did the little shear pin break? I think its to stop people from forcing the ignition with a screw driver or whatever as too much force and it'll just snap and as you've found the barrel just spins round and round.

 

Had it happen to me before.Easily fixed with a small 3mm? or so drill bit. I didnt even pull the ignition apart to do it. 

[wrs 120]

No, it's the main shaft - appears I need photo's to prove it.

How it should be:

How it is - main shaft sheared in two.

 

This is non-repairable and the way the steering column goes together it's most likely a replacement part can't be extracted / fitted. Even if it could it would be old and fatigued.

 

Edited January 27, 2022 by wrs

[wrs 120]

Have decided not to use RFID or a smart key as these can be easy to duplicate unless high levels of encryption or time of flight measurement are used. Instead I'm going to use a USB memory key with a SHA256 encrypted code stored on it based of the USB memory device serial and other hardware characteristics plus my secret key. The ARM will have the secret key stored in it and will be able to create the encrypted key data it expects to get from the USB stick based on the USB stick's hardware credentials. This way any USB stick can be used and a new one can be created at any time without having to update the car end.

This way any USB memory stick can be used as long as it's prepared in a PC with my secret key used to encode the data kept on the USB stick. That way nobody else can duplicate the key unless they now my secret key. It also means anyone else can us the same method and have their own secret key for encryption.

Ultra high plug/unplug count USB3 type A sockets are available (>20k) which will replace the key slot. By using a USB stick that's really small and light and unplugs from my key-ring it can sit in the USB socket with no fatigue from vibration while the key-ring can sit in the console.

If the USB key is plugged in then ACC will be active immediately. Then a single press of the Start/Stop button then holding the start button for 2s OR just holding the button for 2.5s will put the ignition into RUN followed by START.

Removing the USB stick will immediately put everything into STOP.

 

[jom 98]

The current system uses infra-red. Who's going to bother to hack that?

[jon dee 500]

15 hours ago, wrs said:

Have decided not to use RFID or a smart key as these can be easy to duplicate unless high levels of encryption or time of flight measurement are used. Instead I'm going to use a USB memory key with a SHA256 encrypted code stored on it based of the USB memory device serial and other hardware characteristics plus my secret key. The ARM will have the secret key stored in it and will be able to create the encrypted key data it expects to get from the USB stick based on the USB stick's hardware credentials. This way any USB stick can be used and a new one can be created at any time without having to update the car end.

This way any USB memory stick can be used as long as it's prepared in a PC with my secret key used to encode the data kept on the USB stick. That way nobody else can duplicate the key unless they now my secret key. It also means anyone else can us the same method and have their own secret key for encryption.

Ultra high plug/unplug count USB3 type A sockets are available (>20k) which will replace the key slot. By using a USB stick that's really small and light and unplugs from my key-ring it can sit in the USB socket with no fatigue from vibration while the key-ring can sit in the console.

If the USB key is plugged in then ACC will be active immediately. Then a single press of the Start/Stop button then holding the start button for 2s OR just holding the button for 2.5s will put the ignition into RUN followed by START.

Removing the USB stick will immediately put everything into STOP.

 

This post reminded me of this....

Cheers...

[NZ00Z3 189]

And to fix the original problem  https://zroadster.org/threads/z3-spinning-key-lock-barrel-fix.28550/

[wrs 120]

On 1/31/2022 at 3:05 PM, NZ00Z3 said:

And to fix the original problem  https://zroadster.org/threads/z3-spinning-key-lock-barrel-fix.28550/

Nope, the main shaft is broken - the problem has absolutely nothing to do with the barrel spinning (see photos above showing the broken main shaft). If it was a barrel problem I'd be happy. It's not!!

It's spinning because the main shaft is broken, period, no other problem - please read and view the photo's above...

This is a 30 year old car and the problem is not the usual barrel related issue.

[dirtydoogle 383]

Its buggered. Throw it out 

[wrs 120]

On 2/8/2022 at 10:24 PM, dirtydoogle said:

Its buggered. Throw it out 

Done, gone-burgers a week or so ago. The bits are still sitting on the drive next to where I park my car. Rubbish day tomorrow so I night pick them up and put them in the bin to go out...

Actually, I hope you don't mean the car ?? 😉

Edited February 10, 2022 by wrs