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Vehicle security explained: what actually stops a modern Audi being stolen
Following on from our intro post, a few people have asked variations of the same question, so I thought it was worth writing this properly rather than answering many similar questions.
Vehicle security is a confusing market. There are trackers, immobilisers, Thatcham categories, subscriptions, and a lot of marketing language that doesn't explain much. This is our attempt to lay it out plainly, including what things cost and what they cost to keep running.
How modern cars actually get stolen
The first thing worth understanding is that nobody is breaking your window and hotwiring anything. Modern theft is quiet, quick, and mostly digital.
The three methods we see are relay attack, OBD attack, and CAN injection.
Relay is the well-known one. Two people, two devices, one near your front door and one at the car. Your key is sat in the hallway broadcasting, they extend that signal to the vehicle, and the car believes the key is present. Doors unlock, engine starts. Takes under a minute and leaves no damage.
OBD attack usually starts with the thief blocking your key fob's lock command so the car never locks in the first place. They come back, get in, plug into the diagnostic port, and either program a blank key or force a start.
CAN injection is the one that's grown fastest. Rather than needing to get inside at all, they reach the vehicle's data network from an external point and inject a message that tells the car a valid key is present. The car unlocks itself, disarms its own alarm, and starts. From the vehicle's point of view nothing wrong has happened.
The important thing about all three is that the factory alarm and factory immobiliser don't stop them, because they're not being defeated. They're being told, in the car's own language, that everything is fine. That's the gap aftermarket security exists to fill.
Why an aftermarket immobiliser works when the factory one doesn't
This is the bit that clicks for most people once it's explained.
The factory immobiliser is part of the car. It talks over the same network, it uses the same authentication, and it can be addressed by anyone who's worked out how to speak to that network. If a thief can convince the car a key is present, they've beaten it.
An aftermarket immobiliser is not part of that conversation. It doesn't care what the CAN bus thinks. It sits independently and holds a circuit open until it sees a separate authorisation that has nothing to do with the vehicle's own systems, typically an encrypted tag in your pocket.
So the thief can do everything right. They can spoof the key, disarm the alarm, unlock the car, and satisfy every factory system. And the car still won't move, because there's a second gate they don't know about, can't see, and can't address the same way.
That independence is the entire point. It's not a better version of the factory immobiliser. It's a different kind of obstacle.
Where the tracker fits in
An immobiliser and a tracker do different jobs and neither one covers the other.
An immobiliser is preventative. It stops the vehicle being driven away in the first place.
A tracker is what happens if the vehicle goes anyway. It's also doing things the immobiliser can't: alerting you if the car moves without your tag, alerting you to a tow or lift, geofencing, battery disconnect and tamper alerts, and giving a 24/7 monitoring centre something to work with when you report it stolen.
Worth being blunt about what a tracker is not. It is not theft prevention. A tracker has never stopped a car being taken. It improves the odds of getting it back and it gives you evidence and alerts. Sold on its own it's a recovery product.
That's why we recommend both an immobiliser and a tracker; this is not an upsell. An immobiliser without a tracker means that if someone manages to defeat it - perhaps by lifting the car onto a flatbed truck or by taking the vehicle key and your immobiliser tag from you - you will have no means of recovery. In such a case, if your vehicle is stolen and there is no tracking device, it's likely gone for good.
On the other hand, a tracker without an immobiliser means you would be relying solely on recovery efforts after the theft has already occurred. This puts you at a disadvantage, as your vehicle is already stolen, and trying to recover it could lead to further damage.
Thatcham categories, briefly
You'll see Thatcham category S5 and S7 vehicle tracking systems mentioned; in short:
S7 is a tracker with no driver identification. It tells you the car has moved; it can't tell whether it was you.
S5 adds driver recognition tags. If the car moves without a tag present, that's an unauthorised movement. It escalates to the systems monitoring centre immediately, and you'll then receive a phone call to confirm the status of your vehicle. This is what insurers usually mean when they specify a tracker.
Some systems combine both, which is where the Meta Trak DEADLOCK range comes in.
What we recommend and why
For most Audi owners we'd point at a combined S5 tracker and immobiliser system. One install, one app, one subscription, both jobs covered.
Meta Trak S5 DEADLOCK is our common recommendation. Meta supply VAG at dealer level, so the hardware is trusted. DEADLOCK PRO adds OBD port immobilisation on top.
Meta Trak S5 DEADLOCK E-TEC is the one to look at if you're on a mild hybrid, which covers a lot of the current RS range to. On those cars the 48v belt alternator starter can turn the engine over on its own, so conventional starter circuit immobilisation cannot secure vehicle fitted with electrified powertrains. E-TEC disables the start button instead, which means the ignition never comes up and so no ECU ever sees an open circuit. That's why it immobilises without throwing any faults on the dash.
ScorpionTrack is our alternative where it suits the vehicle or budget better.
Pricing, and the bit nobody explains properly
Two costs to be aware of, and we'd rather you saw both up front.
There's the system and installation, paid once. And there's the subscription, which keeps the SIM connected, the app working, and the 24/7 monitoring centre watching.
Prices correct at time of writing
Meta Trak S5 tracker, supplied, fitted, and including 1 years subscription = £484.95
Thatcham S5 tracker
Meta Trak S5 DEADLOCK, supplied, fitted, and including 1 years subscription = £658.95
Thatcham S5 tracker and advanced proximity and remote arming/disarming engine immobiliser
Meta Trak S5 DEADLOCK E-TEC, supplied, fitted, and including 1 years subscription = £788.95
Thatcham S5 tracker and advanced proximity and remote arming/disarming push-to-start immobiliser (for MHEV & EVs - allow can also be fitted to most ICE powertrains too)
Meta Trak S5 DEADLOCK PRO, supplied, fitted, and including 1 years subscription = £788.95
Thatcham S5 tracker, advanced proximity and remote arming/disarming engine immobiliser and remote OBD port immobilisation
Resubscription pricing (for all systems): £189.95 per year, or £499.95 for an additional 3 years
A few honest points on the subscription. It isn't optional, and any tracker sold as "no subscription" either has a short prepaid period built into the price or isn't monitored in any meaningful way. It also isn't a one-off cost you can forget about, so factor it in for the whole time you own the car.
The way we'd frame it is that this is an investment in the vehicle for as long as you have it, not a purchase. Over a five-year ownership on a car worth thirty or forty grand or more, the total spend works out at a small fraction of a percent of the vehicle's value per year, and less than most people spend on insurance excess protection. The immobiliser hardware doesn't expire. The subscription is what you're paying to keep the tracking and monitoring live.
Insurance
Some insurers require an S5 tracker on higher value cars and some offer a discount for one. This varies enormously between insurers and it's worth ringing yours before you buy rather than after. We issue a proof of installation certificate on completion, which is what they'll ask for.
Questions for the thread
Genuinely interested in where people are at with this:
Ask anything on compatibility, spec or pricing and I'll answer in the thread rather than by DM so everyone gets the benefit.
Kind regards
Steve
Following on from our intro post, a few people have asked variations of the same question, so I thought it was worth writing this properly rather than answering many similar questions.
Vehicle security is a confusing market. There are trackers, immobilisers, Thatcham categories, subscriptions, and a lot of marketing language that doesn't explain much. This is our attempt to lay it out plainly, including what things cost and what they cost to keep running.
How modern cars actually get stolen
The first thing worth understanding is that nobody is breaking your window and hotwiring anything. Modern theft is quiet, quick, and mostly digital.
The three methods we see are relay attack, OBD attack, and CAN injection.
Relay is the well-known one. Two people, two devices, one near your front door and one at the car. Your key is sat in the hallway broadcasting, they extend that signal to the vehicle, and the car believes the key is present. Doors unlock, engine starts. Takes under a minute and leaves no damage.
OBD attack usually starts with the thief blocking your key fob's lock command so the car never locks in the first place. They come back, get in, plug into the diagnostic port, and either program a blank key or force a start.
CAN injection is the one that's grown fastest. Rather than needing to get inside at all, they reach the vehicle's data network from an external point and inject a message that tells the car a valid key is present. The car unlocks itself, disarms its own alarm, and starts. From the vehicle's point of view nothing wrong has happened.
The important thing about all three is that the factory alarm and factory immobiliser don't stop them, because they're not being defeated. They're being told, in the car's own language, that everything is fine. That's the gap aftermarket security exists to fill.
Why an aftermarket immobiliser works when the factory one doesn't
This is the bit that clicks for most people once it's explained.
The factory immobiliser is part of the car. It talks over the same network, it uses the same authentication, and it can be addressed by anyone who's worked out how to speak to that network. If a thief can convince the car a key is present, they've beaten it.
An aftermarket immobiliser is not part of that conversation. It doesn't care what the CAN bus thinks. It sits independently and holds a circuit open until it sees a separate authorisation that has nothing to do with the vehicle's own systems, typically an encrypted tag in your pocket.
So the thief can do everything right. They can spoof the key, disarm the alarm, unlock the car, and satisfy every factory system. And the car still won't move, because there's a second gate they don't know about, can't see, and can't address the same way.
That independence is the entire point. It's not a better version of the factory immobiliser. It's a different kind of obstacle.
Where the tracker fits in
An immobiliser and a tracker do different jobs and neither one covers the other.
An immobiliser is preventative. It stops the vehicle being driven away in the first place.
A tracker is what happens if the vehicle goes anyway. It's also doing things the immobiliser can't: alerting you if the car moves without your tag, alerting you to a tow or lift, geofencing, battery disconnect and tamper alerts, and giving a 24/7 monitoring centre something to work with when you report it stolen.
Worth being blunt about what a tracker is not. It is not theft prevention. A tracker has never stopped a car being taken. It improves the odds of getting it back and it gives you evidence and alerts. Sold on its own it's a recovery product.
That's why we recommend both an immobiliser and a tracker; this is not an upsell. An immobiliser without a tracker means that if someone manages to defeat it - perhaps by lifting the car onto a flatbed truck or by taking the vehicle key and your immobiliser tag from you - you will have no means of recovery. In such a case, if your vehicle is stolen and there is no tracking device, it's likely gone for good.
On the other hand, a tracker without an immobiliser means you would be relying solely on recovery efforts after the theft has already occurred. This puts you at a disadvantage, as your vehicle is already stolen, and trying to recover it could lead to further damage.
Thatcham categories, briefly
You'll see Thatcham category S5 and S7 vehicle tracking systems mentioned; in short:
S7 is a tracker with no driver identification. It tells you the car has moved; it can't tell whether it was you.
S5 adds driver recognition tags. If the car moves without a tag present, that's an unauthorised movement. It escalates to the systems monitoring centre immediately, and you'll then receive a phone call to confirm the status of your vehicle. This is what insurers usually mean when they specify a tracker.
Some systems combine both, which is where the Meta Trak DEADLOCK range comes in.
What we recommend and why
For most Audi owners we'd point at a combined S5 tracker and immobiliser system. One install, one app, one subscription, both jobs covered.
Meta Trak S5 DEADLOCK is our common recommendation. Meta supply VAG at dealer level, so the hardware is trusted. DEADLOCK PRO adds OBD port immobilisation on top.
Meta Trak S5 DEADLOCK E-TEC is the one to look at if you're on a mild hybrid, which covers a lot of the current RS range to. On those cars the 48v belt alternator starter can turn the engine over on its own, so conventional starter circuit immobilisation cannot secure vehicle fitted with electrified powertrains. E-TEC disables the start button instead, which means the ignition never comes up and so no ECU ever sees an open circuit. That's why it immobilises without throwing any faults on the dash.
ScorpionTrack is our alternative where it suits the vehicle or budget better.
Pricing, and the bit nobody explains properly
Two costs to be aware of, and we'd rather you saw both up front.
There's the system and installation, paid once. And there's the subscription, which keeps the SIM connected, the app working, and the 24/7 monitoring centre watching.
Prices correct at time of writing
Meta Trak S5 tracker, supplied, fitted, and including 1 years subscription = £484.95
Thatcham S5 tracker
Meta Trak S5 DEADLOCK, supplied, fitted, and including 1 years subscription = £658.95
Thatcham S5 tracker and advanced proximity and remote arming/disarming engine immobiliser
Meta Trak S5 DEADLOCK E-TEC, supplied, fitted, and including 1 years subscription = £788.95
Thatcham S5 tracker and advanced proximity and remote arming/disarming push-to-start immobiliser (for MHEV & EVs - allow can also be fitted to most ICE powertrains too)
Meta Trak S5 DEADLOCK PRO, supplied, fitted, and including 1 years subscription = £788.95
Thatcham S5 tracker, advanced proximity and remote arming/disarming engine immobiliser and remote OBD port immobilisation
Resubscription pricing (for all systems): £189.95 per year, or £499.95 for an additional 3 years
A few honest points on the subscription. It isn't optional, and any tracker sold as "no subscription" either has a short prepaid period built into the price or isn't monitored in any meaningful way. It also isn't a one-off cost you can forget about, so factor it in for the whole time you own the car.
The way we'd frame it is that this is an investment in the vehicle for as long as you have it, not a purchase. Over a five-year ownership on a car worth thirty or forty grand or more, the total spend works out at a small fraction of a percent of the vehicle's value per year, and less than most people spend on insurance excess protection. The immobiliser hardware doesn't expire. The subscription is what you're paying to keep the tracking and monitoring live.
Insurance
Some insurers require an S5 tracker on higher value cars and some offer a discount for one. This varies enormously between insurers and it's worth ringing yours before you buy rather than after. We issue a proof of installation certificate on completion, which is what they'll ask for.
Questions for the thread
Genuinely interested in where people are at with this:
- What are you running at the moment? Anything aftermarket, or factory only?
- Has your insurer asked you for a tracker, and did they specify S5 or just "a tracker"?
- Has anyone here had a car go, or an attempt made? What was taken and how?
- If you've looked at aftermarket security and decided against it, what put you off? Price, subscription, worry about warranty or wiring?
- Anything you want explained that this post didn't cover.
Ask anything on compatibility, spec or pricing and I'll answer in the thread rather than by DM so everyone gets the benefit.
Kind regards
Steve