DIY Batteryless SmartTag

[SlowCar]

like how the Japanese do ETC system... when buying JDM cars....

*I'll pay you for this*

ya ya... i'll pay too if someone can do that....

 

[zeus83]

kudos bro! go patent you invention!

 

[feipepe]

I'm sure many people already done this.

But here is how I did it.

Prepare the parts :- a 9V IC regulator. ***7809, 2 pcs of 100uF/16V e.capacitors, and a heatsink and pcb.

Then solder all the parts together. The IC pin when seen from front side is Input-Ground-Output. Connect the E.cap at input to ground and output to ground respectively.

Buy the ciggarete jack (since im not smoking, better put it to good use) and open it up and rig a switch to turn it on and off.

Solder the input and output to the regulator. Need to cut the battery connector inside the battery compartment of the smarttag.

On the battery cover of smart tag, u will notice a small notch. Cut it
out for the wire to go out.

Finally cover it up nicely. Done!

And you will never need a battery ever again. Huhu...

Next DIY is to put a LED lighting to the SmartTag LCD screen.. hehe..

hi bro,
quick interested with this DIY matter, unluckly my lap top don't show any photo detail. wanna to know how to view it?

 

[Dayline668]

If u a heavy smart tag user can consider buying a rechargeable 9V, can use for long time.

 

[stupidcar]

Aww man, TS last active on 2011.
Can someone tell me which screw to use?
And also if anyone can reupload the pics.

 

[Izso]

donCityZ hasn't logged in for a loooong time

 

[Supra_Fanatics]

Use a rechargeable battery is a good idea. Unless got somewhere to hide like stupidcar suggested. If your cover is transparent
better stupidcar. So that infrared can reach.

 

[stupidcar]

Use a rechargeable battery is a good idea. Unless got somewhere to hide like stupidcar suggested. If your cover is transparent
better stupidcar. So that infrared can reach.

I think if there is some solid blocking the infrared can't reach too.
If were to desolder everything, they say it will burn it(fragile chips),
and also the current will drop.
Basically, must use the whole damn board.
Damn tag, you are too big.

 

[deenweirdoz]

nice one!

 

[Supra_Fanatics]

I think is a good idea but not recommended. Will fry the chips inside later.
Like they said in car chargers are not good for our phone. Eventually our phone battery lifespan ends faster.

Voltage in the car is not stable. Can be high or low at times.

 

[stupidcar]

I think is a good idea but not recommended. Will fry the chips inside later.
Like they said in car chargers are not good for our phone. Eventually our phone battery lifespan ends faster.

Voltage in the car is not stable. Can be high or low at times.

That where a calculations of resistor needed.
Put a resistor that resist 4 volts.
Car: 12V
Needed: 9V

 

[shiroitenshi]

That where a calculations of resistor needed.
Put a resistor that resist 4 volts.
Car: 12V
Needed: 9V

Actually car is not 12V, car is 14.5V. 12V is the battery, once you start your car, the alternator kicks in and you get 13.5-14.5V, I always use 14.5v for car to calculate resistance required based on voltage and amp draw.

Sent from my GT-N8000 using Tapatalk 2

 

[stupidcar]

Actually car is not 12V, car is 14.5V. 12V is the battery, once you start your car, the alternator kicks in and you get 13.5-14.5V, I always use 14.5v for car to calculate resistance required based on voltage and amp draw.

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Really?
If i resist base on 12V, my leds are gonna burst!

 

[shiroitenshi]

not really, overvolting leds a bit don't usually do much apart from shorter lifespan. overvolting a lot that usually kills it.

But yes, you can try with a multimeter to see before and after you start the car. its 11-12, before start, 13-14.5v after start engine and it runs the alternator.

dont test at the ciggy plug area, rarely you get full voltage unless its a new car.


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[stupidcar]

not really, overvolting leds a bit don't usually do much apart from shorter lifespan. overvolting a lot that usually kills it.

But yes, you can try with a multimeter to see before and after you start the car. its 11-12, before start, 13-14.5v after start engine and it runs the alternator.

dont test at the ciggy plug area, rarely you get full voltage unless its a new car.


Sent from my GT-N8000 using Tapatalk 2

But dude, i know input is more than 12V.
But output, the voltage is 12v right, TO those electronics(air cond, lights)?

 

[shiroitenshi]

But dude, i know input is more than 12V.
But output, the voltage is 12v right, TO those electronics(air cond, lights)?

nope, most cars actually run fine with 14.5v, they were designed to, but they can also run with less voltage. Thats why I said if car, always calculate resistance required based on load using 14.5v

The battery is 12v. It only works to power the ecu, blower fan, lights, accessories, and the starter UNTIL the alternator takes over. The alternator will be the main source once engine starts, and the battery actually becomes a (consumer) or more accurately. a "load" on the electrical system in the car.

But this is also not 100% true that all accessories run 14.5v. Do remember that most car sensors runs on 5V, so your ecu does already have circuits to bring down the 12v/14.5v to 5v for the sensors. But never tap these wires for power, as the sensors use resistance/inductance/voltage to measure stuff, and you never ever want to simply add a load on its circuit.

Do understand that electronic do work in a "range" of voltages, not a single voltage. most auto specific electronics work up to 15v or 26V (for lorries)

You cannot consider voltage inductance and resistance in isolation as they are closely related.

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[punk]

That where a calculations of resistor needed.
Put a resistor that resist 4 volts.
Car: 12V
Needed: 9V

Why so hard?

----------------------------
This charger regualate to 9V 0.5A output.
Dont go simply buy any charger at supermarket and modify the connector because different output.

 

[stupidcar]

nope, most cars actually run fine with 14.5v, they were designed to, but they can also run with less voltage. Thats why I said if car, always calculate resistance required based on load using 14.5v

The battery is 12v. It only works to power the ecu, blower fan, lights, accessories, and the starter UNTIL the alternator takes over. The alternator will be the main source once engine starts, and the battery actually becomes a (consumer) or more accurately. a "load" on the electrical system in the car.

But this is also not 100% true that all accessories run 14.5v. Do remember that most car sensors runs on 5V, so your ecu does already have circuits to bring down the 12v/14.5v to 5v for the sensors. But never tap these wires for power, as the sensors use resistance/inductance/voltage to measure stuff, and you never ever want to simply add a load on its circuit.

Do understand that electronic do work in a "range" of voltages, not a single voltage. most auto specific electronics work up to 15v or 26V (for lorries)

You cannot consider voltage inductance and resistance in isolation as they are closely related.

Sent from my GT-I9100G using Tapatalk 2

So when I actually tap those electronics wires, its 12V ma. NO?

---------- Post added at 02:58 PM ---------- 6 hour anti-bump limit - Previous post was at 02:58 PM ----------

Why so hard?

Hard weh. :hahaha:

 

[shiroitenshi]

So when I actually tap those electronics wires, its 12V ma. NO?

Yes, but only if engine is off/alternator not running.

Always estimate for 14.5V for car stuff since you run most stuff with the engine on.

Those 12V they put on amplifiers is to simplify things only, they already design for 14.5+V

but seriously since got adapter, the only reason you'd want to do mod to smart tag is to relocate the sensor somewhere. I plan to do, but so far cannot find spoiled unit i can crack open and see.

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[stupidcar]

Yes, but only if engine is off/alternator not running.

Always estimate for 14.5V for car stuff since you run most stuff with the engine on.

Those 12V they put on amplifiers is to simplify things only, they already design for 14.5+V

but seriously since got adapter, the only reason you'd want to do mod to smart tag is to relocate the sensor somewhere. I plan to do, but so far cannot find spoiled unit i can crack open and see.

Sent from my GT-I9100G using Tapatalk 2

Really confused here.
My friends all said its okay. They have done their own lights.
Base on 12v as voltage source. Its fine.

Hmm, there are 2 things weh, can't really desolder it.
1 sensor another 1 i forgot what but both are important.