RF Interference Like You’ve Never Seen Before

A wireless camera that can drain a car’s battery from a distance? I thought I’d seen it all, but that? Yep.

OK, this one is so weird that you're likely not going to believe what follows. Notice, however, that this is not the April Fools column, and, in fact, the following is 100% true.

Farpoint Group's erstwhile Operations Manager, Donna Diamond, recently set out to buy a new car. No drama here - she's a loyal Jeep girl, and came home with Jeep #6 - a 2014 Cherokee. However, she noticed later in the afternoon on the day of delivery that the car wouldn't start. As it turns out, the battery was dead. OK, being an engineer, I know all about infant mortality, and the dealer checked it out. But, surprisingly, they couldn't find anything wrong, and home it came.

And the next morning, the battery was dead. I noticed the previous evening that the instrument panel backlight would come on from time to time, strange behavior, and likely the source of the dead-battery condition. Back to the dealer. They decided the battery was bad, and replaced it.

Home it came again - and the same behavior with the backlighting immediately returned. The tech from the dealership paid Donna a visit, and his laptop-based diagnostics showed - well, nothing, although he did agree that there was a problem in there somewhere. His recommendation was to replace the receiver in the car that listens to the key fob, along with both fobs as well. And he put all of that on order.

Being a wireless type, I assumed some kind of defect in the receiver. Perhaps it was out of spec, paying attention to signals it should ignore, or perhaps a software problem, or perhaps a major design defect - anything could be possible here. Placing the car in the driveway instead of the garage made the problem go away, so I concluded that something radiating in the house was to blame. I did a quick sweep with a spectrum analyzer, but I don't know what frequencies the fob operates on, so that exercise wasn't too productive other than to note a 20 dB difference in signal strength between the garage and  the driveway just outside the garage.

Donna had been using a ZyXEL IPC4605N wireless camera for security - sort of. This camera was actually a pseudo-gift from me, and didn't actually work. In fact, this is a seriously bad product that I never could get operational (see my review here; there's a link to the product page here as well if you're interested), but I thought the flashing lights might be a deterrent nonetheless - or at least a bad one-shot attempt at techno-humor.

Anyway, the camera was right near the garage, so I just turned it off. Voilà - problem solved. No more random backlight flashing, and presumably the car will start in the morning.

But - this is still an issue. An errant wireless device causing a car battery to go dead? Jeep still has a problem here - as might ZyXEL, but that's another story. I'd want to know if there are any FCC violations going on with this unit, but Jeep still needs a fix here.

I'm going to loan Jeep the camera, and insist that Donna get a call and a repair when there's a fix. But who might have thought that an issue with wireless security and integrity would manifest itself like this?

A pleasant weekend to all. And, yes, my cold is better.

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