Older cars in Northampton, no keyless entry — and the OBD port

Almost everything written about car theft in the last few years has been about relay attacks, which has left a lot of Northampton drivers with an older car feeling comfortably outside the conversation. No keyless entry, no relay, no problem. The first two are true. The third is not, and the reason sits in the driver's footwell.

Every vehicle sold in this country since around 2001 has an OBD socket — a standardised diagnostic connector, usually within reach of the pedals, sometimes behind a small flap. It exists so that a garage can plug in and read fault codes, and it is genuinely useful. It also has the ability, on a great many vehicles, to write to the car rather than only read from it, and one of the things it can write is a new key.

The tools that do this are not exotic. They are sold openly as locksmith and trade equipment, they cost a few hundred pounds, and on plenty of models the process of pairing a blank fob takes about a minute. The car does not treat the new key as suspicious, because as far as it is concerned a garage has just programmed a replacement in the normal way. The result is a working key, in somebody else's hand, for a car that is still sitting on your drive.

What that method needs and a relay does not is a moment of physical access to the cabin. On older vehicles that is rarely the obstacle it sounds like — door locks on a fifteen-year-old car are not a serious barrier, and on many the socket is reachable through a door glass gap without a person needing to be fully inside. There is normally no broken glass, because breaking glass is loud and unnecessary.

Then there is the part that makes it worse rather than better: once it has been done, nothing about the theft looks like a theft. The car is unlocked with a key and driven away with a key. There is no damage, no alarm and no forced entry, which is the same evidential problem keyless owners run into with their insurers, arrived at by a completely different route.

Around Northampton this matters more than it might elsewhere, because the older vehicle is often the second one — the runaround, the van, the tow car, the classic in the garage — and it is almost never the one anybody has thought about protecting. It is also the one most likely to be parked out of sight, which is precisely the condition somebody needs to sit in a footwell for a minute without being disturbed. With the M1 and the A45 a few minutes away in most directions, the exit is not the hard part either.

There are OBD blockers and port locks sold for this, and they are better than nothing. What they are is an obstacle in the footwell that has to be removed, and somebody who has come equipped generally can. They also have to be refitted every time your own garage takes them off, which is the same reliability problem as a signal pouch.

The approach that closes it properly is to make a key insufficient rather than to defend the socket. A Ghost II or a CAN Phantom sits on the car's own data network and will not let the engine fire until a sequence you chose is entered on buttons already in the cabin. It does not matter whether the key in the ignition was relayed, cloned, programmed through the OBD port that morning, or is the genuine article the previous owner never handed over. No sequence, no start.

These systems fit to older vehicles perfectly well, and because nothing is cut, drilled or spliced they go into something you care about without altering it. Send us the registration and we will tell you what your car has, what it is exposed to, and what it would cost — with no obligation to book anything.