Sustainable Siren

::: nBlog :::

Yesterday I decided to investigate a small issue with my venerable Saab, namely the hyperactivity of the theft alarm system. Every now and then, when activated, it used to go off for a few seconds for no apparent reason, and sometimes the console display (SID) told me ‘Service Theft Alarm’. The system, from 2003, is quite sophisticated with several sensors around the car.

The authorized service dealer told me straightforwardly that this is a known issue, related to the actual alarm siren at the left front wheel fender. The siren has its own backup battery in case the thief disconnects the car’s main battery. However, the spare part used to be the whole siren component, which is no longer manufactured. Saab has, anyway, ceased to exist as a consumer car manufacturer.

Nevertheless I decided to take a look at the siren component. It turned out to be a hard plastic box, with bus connection and two molded loudspeakers. As I anticipated by the dealer’s comments, it was fused together with no screws or other opening possibilities.

Encouraged by a few enthusiast bulletin boards I decided to cut the box open with a Dremel drill to see if the battery could be replaced. After a lot of flying plastic and two cutting discs I managed to open it without damaging any electronics. There they were, two 3 volt lithium batteries soldered on the circuit board, with printed expiration date of 8/2009. The most surprising thing was that the box had screw holes, and plenty of space for a battery holder. It later turned out that until 2000 models the box did have screws.

As these were standard camera batteries, I was able to replace them with relatively small effort. Putting the box together with blue silicone and screws was also swift and easy. After two hours and 4€ for the new batteries I again had a fully working theft alarm.

What left me wondering though is that the car’s electronic control unit (ECU) knew the battery voltage via the CAN bus, and intermittently issued the SID message to me, based on the low value. So at least one Saab engineer thought that the battery could be replaced. Comforting.

This kind of information can easily be utilized by the manufacturer or dealer, once these cars are adequately connected. If Saab still existed and had spontaneously offered me battery replacement kit or even replacement service, I definitively would have taken the offer and saved two hours. Also the battery manufacturer could have been part of the real-time business chain.

The new (Connected Spime) car business model requires that each and every component in the car is managed digitally and remotely once the car is manufactured. This will have profound effects to Research and Development, but most importantly it totally changes the business relationship between the manufacturer and customer, by transforming the car into an ever-improving service continuum.

//Pasi