Found Possible Tracking Device in Car, Please Help

Thread Starter


Joined Apr 1, 2006

I know this might not be the correct place for this question but I didnt know where else to post this, where enough people would see it.

My car needed to have some things fixed on it and when I got it back I noticed this strange looking box in the trunk and I have been around cars for a long time and never ever seen anything like this. When I asked the guy who fixed it, he said it was there to help with the radio, but I know its not because when I disconnect it...the radio still works. I tried everything accpet from beating this guy to the ground and unless I know for sure what it is, I dont want to cause any problems.

I'm not sure if its a tracking device, or some kind of listening device. Please try and help me figure this out. I dont know where else to turn for help. Here are the pic's:

Again, please try and help me out on this. I have shown this to alot of people and everyone says that they dont know what it could be used for. Thanks so much for your effort.



Joined Oct 14, 2005
Was it connected to something or just left lying in the trunk?

It seems harmless enough, just a bunch of logic ICs, a transistor and a relay. I don't think it is a tracking or listening device.


Joined Jan 28, 2005
I have two observations:

1. All of the devices were manufactured in 1989 based on the visible date-codes on the devices.

2. Today is April the 1st.



Joined Jan 10, 2006
Looks like a timer.... possibly a turbo delay timer, or a Glo-plug warmer timer, or an Electric antenna extend/retract circuit.. Definately no RF stage for radio tracking.
As for April the 1st, a more elaborate hoax may have been better.

(nb, your GPS enabled Radar detector or cellphone probably has more tracking ability than that circuit).....


Joined May 16, 2005
We've got three types of logic gates, a power transistor, and a standard issue Illuminati mind-control module. I wouldn't worry about it. Move along. Move along.


Joined Jan 18, 2005
Am I missing something? Did the repair guy wire in a plug to plug this thing into or did he plug it into an existing plug already on the vehicle?

Its definately NOT a transmitter or receiver. Apparently some kind of control device. But to control what? If it was'nt there before and has no apparent effect on the operation of "anything" then I would ask - how significant is it? In any event, the repair guy owes you a satisfactory explanation as to the functionallity of the thing at least. Tell him you want the manufacture and/or distrubuting source of the "mysterious" box.

You gotta watch these repair places some times. I took my vehicle in for some basic exhaust work and when I picked up the car, one of the guys said - what kinda radio is that you have there, it sure aint no CB! - - - DUH!

The radio was a 2-meter (144 to 148-MHz) Amatuer Radio transceiver cabable of receiving public service frequencies. Needless to say, I dont take my car there anymore for repair work.

Anyway, I would definately want some answers if I were you.


Joined Oct 11, 2004
There was a case in the UK a few years ago of a corrupt burglar alarm supplier/installer. He fitted a timer in each alarm he installed that would make it malfunction when it was out of its warranty period. He made a pile of money.

He was caught out when one of his alarms 'broke down' when he was on holiday (something he had not considered when he programmed the timers) and the householder called in another repair man.


Joined Jul 24, 2006
n9xv said:
Am I missing something? Did the repair guy wire in a plug to plug this thing into or did he plug it into an existing plug already on the vehicle?
I have seen alot of stuff like this when I worked for a stereo place. It's usually hidden in the upper areas of the trunk. It was probably pulled down or fell and was noticed when you got the car back due to the upgrade syndrome effect. {Explained, you are hypersensitive to change when you have a car to the shop or your computer just got a service pack.}

It is likely one of the following, Power antenna circuit, Power lock module, or one of the hundreds of body control modules in cars now.

Just my $0.02


Joined Jun 29, 2007
I have to tell you. We have an 8 disk cd player in the trunk of our Jaguar and with the 8 plugs on this thing I can't help but wonder if it has something to do with a stereo system contrary to what some people may think and being a toshiba type of circuit it may very well be. I can't imagine what else it would be. Listening device .. I wouldn't think so but with the various areas for plug in's (especially 8) I find it really kind of unique when you can use an 8 disk cd changer cartridge in the electronic system. Just a thought! Good luck in your search.


Joined May 16, 2005
So... would a ten disk system have ten pins? :eek:

Maybe the unidentified gizmo is for controlling 8-balls or feeding the pet octopus. :D If it had only seven pins, it could be a day-planner. :rolleyes:


Joined Jun 30, 2006
Mystery box is a relay

With a 2SD560 controlling the DPDT relay. I assume is controlled by the logic ICs. I'm not going to make a schematic. ;)

And with some other searching it's a spiffy little relay device for controlling...
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Re: Found Custom Circuit in Car, Please Help
« Reply #4 on: April 02, 2006, 07:58:21 PM »
Install bay has a couple of Installers that I dentified it as an antenna controll box that controlls the Electric Antenna.
Here is what they said.
i'm guessing a power antenna control box... Year, make and model of vehicle would be most helpful of course.
Definately the power antenna control box most likely from a Toyota/Lexus. It was probably just loose in the trunk because the antenna is broken, and they unplugged it to keep the antenna motor from running. Just a guess though Wink


Joined Apr 27, 2007
Your circuit seems to be a logic circuit of some sort. The 74HCxx chips from Toshiba are high speed CMOS gates (four gates for each chip). The NEC D560 is a Darlington power transistor (as I would expect) (alternative reference 2SD560), most likely used for the output (as a key to control a big load - note that the transistor might operate in the saturation region, because of the absence of an heatsink, but it depends also on the load controled).
The black big package from Japan seems to be a relay of some kind. I see that the relay is connected to the middle pin of the transistor, which is the output pin, so it seems that the transistor is driving the relay. Also, the relay contact pins are connected to the connector, being the relay the final output stage.
The circuit seems some kind of switch, maybe a delay switch because of the excessive use of capacitors. I never came across with that configuration across, but I can tell what it isn't:
- An audio circuit (amplifier stage, filter), since relays are definitely not used in analog output stages, and transistors used in audio circuits work in the active region, not in the saturation region (plus I never saw logic gates being used as audio stages).
- A tracker, detector, for the same reason before plus, the absence of inductors used in radio circuits.

Well, you should check the cable he used there, maybe only two wires are really functional (the power and ground wire), thus acting your circuit as a placebo and consuming power.