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Discussion Starter · #1 ·
sup guys. so i just received my sponsored 16.7 million color underglow kit from Varad and it looks pretty **** intense even for me. i dont have a lot of experience nor knowledge when it comes from running wire from outside to the inside so i was wondering if anyone had any suggestions or where to run the four cables from the light bars from the underside of the car to the inside. they are very thick and have a clip connector on the end which makes running through grommets a paint in the ***. i could always clip it off and resolder it back on once inside but thats only if i have to. also if i could get some info on where the 12v ignition circuit is (the ones thats on when the key is turned to accessory or further) and also an easy access point to a speaker + circuit as well as courtesy light that would be fantastic and you would help me out big time. thanks in advance.
 

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Almost all your questions are answered on my website, linked in my signature below.
  • run cables from the inside to the outside via a hole in your front door rubber wire conduits (see "15 - Light Frenzy 2") then under or thru your mudguards
  • for a 12v ignition circuit, I used the gray wire under the steering column (also in "15 - Light Frenzy 2")
  • for a 12v accessory circuit I tapped off the cigarette lighter socket (see "06 - Stealth Sub") since my OEM head unit does not have an external amp turn-on signal wire. Be careful since the wire for this circuit seems rather small. I power my monoblock amp and foglights via a separate dedicated wire with an inline fuse run from my battery.
  • for courtesy/dome light wires, look in "02 - Light Frenzy"
  • speaker + circuit? If you mean + for the left front speaker, you can tap off the pink - purple wire in the drivers door conduit
Hope this helps!
 

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Discussion Starter · #4 ·
hey brickpig. well im looking to tap into a circuit thats on as long as the key is not in the off position. i think accessory is also on when you start the engine as well. so im looking for just accessory i guess.

as for the positive speaker terminal thats the pink/purple wire i take it? i dont know why it wants a positive speaker terminal tap but i guess we will see.

and as for the courtesy light i want to tap into the fade on fade off function of the dome light when the doors open and what not. im confused on if i should tap into the fade on/off ground or the constant power? keep in mind im sure these taps for the underglow control unit are only relays (i would assume) so if you could clear those up that would be fantastic as those are the only things i need help tapping into.

as far as running the cable i actually found a method that will work better for me. ill be running them through the body plugs in the front foot wells underneath the carpet and foam and through the rear plug in the back under the spare tire.

so thanks for the help man. youve done some good work.
 

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well im looking to tap into a circuit thats on as long as the key is not in the off position. i think accessory is also on when you start the engine as well. so im looking for just accessory i guess.

and as for the courtesy light i want to tap into the fade on fade off function of the dome light when the doors open and what not. im confused on if i should tap into the fade on/off ground or the constant power? keep in mind im sure these taps for the underglow control unit are only relays (i would assume) so if you could clear those up that would be fantastic
Typically when cranking the engine, power to Acc items are cut. So by tapping into Acc, there would be power only in the Acc or On (engine running) positions. Example: car is on and engine is running, radio is playing but then engine dies. The radio still plays when key is On even if engine is not running. While cranking the starter, power to the radio is cut. So Acc wire only has power in the Acc or On key positions. If your lights draw a lot of power, I'd use a relay with the coil energized by the Acc wire (because the Acc wire looks kinda thin to me).

As far as the dome light, it appears that the fade on/off ground works by increasing/decreasing the voltage potential. So to turn "off" the dome light, rather than the ground wire being increased to infinity resistance (therefore creating a non-connection), the ground wire instead is being increased from 0 volts to +12 volts. Since both sides of the dome light see +12 volts, the effect is no voltage potential, so zero volts, so no light. I tried putting an SPDT relay across the dome light wires (constant power and fade on/off ground) but the relay chattered (produced a buzzing sound) as the dome light faded on or off. I did not measure voltage or resistance on the fade on/off wire but instead ran the relay buzz behavior by an Electrical Engineer at work, who suggested replacing the relay with a PNP transistor (see Light Frenzy 2). The PNP transistor elimated the buzzing sound yet still isolated the underglow load from the dome light ECU. The PNP transistor is good for up to a couple of amps but needs a heat sink (otherwise it gets kinda warm).

Good luck with your project!
 

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Discussion Starter · #7 ·
you must be an electrical engineer. because i like totally lost you on most of that. the control unit draws its main power from the battery directly. the rest of the stuff like the accessory (Which yes its what i want) the speaker terminal, courtesy dome light and stuff, those arent drawing power. merely signaling the control unit what to do. i havent really used relays before. im a simple LED guy. you want something LED i can make it. no matter how bright or intese. i work with LEDs, resistors, and LED drivers. thats about it. lol.
 

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you must be an electrical engineer. because i like totally lost you on most of that.
Close. I'm a mechanical engineeer. :)

...the courtesy dome light...those arent drawing power. merely signaling the control unit what to do.
Be careful on the dome light. In the past, dome lights received constant power and were controlled on/off via the pin switches in the doors which provided a path to ground. With this car (and most likely others that fade the dome light) the pin switches in the doors still provide ground, but all 4 are connected to the ECU which as explained earlier, turns "off" the dome light by raising what in the past was "ground completion" (ie zero volts or ground) to +12 volts instead.

In other words, if your control unit is expecting to see ground (as with cars in the past) and instead sees +12 volts, I don't know what will happen...

Also replacing an ECU is ~$400. So be careful.
 

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Discussion Starter · #9 ·
yeah its not going to work. unfortunatley because it wants a postive input i dont think it would work on the negative end... it might i dunno. i dont think it will fry it since its not drawing any power. well some but just enough for a signal.. BUT could i possibly tap into the circuit that makes the lights flash when i lock the doors? if so wheres that? lol.
 
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