Wiring question: Cig lighter cables

[morph2k4]

I bought the inbay wiress charging pad and I plan to run the wires into the cable for the cigarette lighter. Rather than using the splicers, I figured I would just clip off the cig lighter cable and solder the wires directly onto the plugs from the charger. Here is the underside of the cig lighter assembly and the cable for the charger:



My questions are:

1. how do I map the red/brown/grey wires onto the red/black wires for the charger?
2. Is there any risk to doing this the way I'm suggesting, where I just attach the cig lighter plug to the end of the charger cables? I know I'm losing the ground and adding an inline fuse on the red cable for the charger, if that matters.

[mys4.org]

Might be easier to get a fuse slice/splitter/tap go directly from the fuse box. That way you don't mess with the stock cig light wiring. Plus it is easier to remove and return to stock if needed.

Example: https://www.amazon.com/dp/B00OZFNJI6..._yO9uCbZVXC1FZ

[DBFL]

The three wires should be power, ground and illumination. You can test it with a test light. Chances are that brown is ground, red is power, and grey is illumination. But you’ll need to test it to be sure.

You also need to see what size fuse is on the cigarette lighter circuit. If it’s smaller than the fuse for your charger kit, you’ll overload the circuit and pop the fuse. Also, don’t increase the size of that fuse as there would be other things on the same circuit that you’d damage with too much amperage. If that’s the case, you’re better off running it to the fuse block.

[hilmar2k]

What is the final plan for wireless charging? Is there a model specific charger available? I've long wanted to add wireless charging, but have never found a really good solution.

[morph2k4]

The three wires should be power, ground and illumination. You can test it with a test light. Chances are that brown is ground, red is power, and grey is illumination. But you’ll need to test it to be sure.

You also need to see what size fuse is on the cigarette lighter circuit. If it’s smaller than the fuse for your charger kit, you’ll overload the circuit and pop the fuse. Also, don’t increase the size of that fuse as there would be other things on the same circuit that you’d damage with too much amperage. If that’s the case, you’re better off running it to the fuse block.

What is illumination? Is that the ring lighting up? How can that run off a single conductor? What is a test light?

As for the fuses, the cable is purple and says "3" on it. I need to compare that to what the cigarette lighter connects to on the fuse box?

Thank you!

[morph2k4]

What is the final plan for wireless charging? Is there a model specific charger available? I've long wanted to add wireless charging, but have never found a really good solution.

I've designed a 3d printed component that will replace the entire ash tray assembly with a wireless charging dish. Still hammering out the details, but I'll be posting it online once I get it fully tested and fitted. I'm using the universal inbay qi charger.

[Fresh.S4]

fairly certain that isnt an ILLUM wire (that should feed off the 12v)

my guess is its a switched 12v (meaning it goes on/off with the ignition)
but yes best way is just to test.
use a volt meter and go red/ brown then test grey/brown

[hilmar2k]

I've designed a 3d printed component that will replace the entire ash tray assembly with a wireless charging dish. Still hammering out the details, but I'll be posting it online once I get it fully tested and fitted. I'm using the universal inbay qi charger.

Yeah, I could be very interested in one of those pieces.

[Envy187]

Yeah, I could be very interested in one of those pieces.

How crappy are all of your cell-phone's batteries that having ANY charger in your car is required as an option?

Do none of you have office jobs and keep your cell-phones topped up/pay attention to your current battery life and charge it accordingly?

To each their own...but I've never had a cell-phone charger of ANY sort in any of my vehicles, and am quite content.

I stream music 24/7 when I drive, use my cell-phone on the regular, and have never needed a charge during my commute(s). Only when I reached my destination do I plug in, if necessary.

Perhaps I'm one of the lucky few?

[hilmar2k]

How crappy are all of your cell-phone's batteries that having ANY charger in your car is required as an option?

Do none of you have office jobs and keep your cell-phones topped up/pay attention to your current battery life and charge it accordingly?

To each their own...but I've never had a cell-phone charger of ANY sort in any of my vehicles, and am quite content.

I stream music 24/7 when I drive, use my cell-phone on the regular, and have never needed a charge during my commute(s). Only when I reached my destination do I plug in, if necessary.

Perhaps I'm one of the lucky few?

You're right, I don't need it (like at all), but it's cool nonetheless. I wouldn't spend a lot of money on it, but it would be nice to have the ability to just drop my phone and have it be charging.

[Envy187]

You're right, I don't need it (like at all), but it's cool nonetheless. I wouldn't spend a lot of money on it, but it would be nice to have the ability to just drop my phone and have it be charging.

Thank you for responding, hilmar2k. I apologize if you felt that I singled you out in particular; I merely used your quote to speak my mind.

In a lot of modern cars, that technology is already available...so it would definitely be a neat feature to see in our B8/B8.5 models, when/if you need it!

[DBFL]

What is illumination? Is that the ring lighting up? How can that run off a single conductor? What is a test light?

As for the fuses, the cable is purple and says "3" on it. I need to compare that to what the cigarette lighter connects to on the fuse box?

Thank you!

There is an illumination circuit. It’s what turns on the lights on the buttons when you turn on your headlights. In the case of the cigarette lighter, yes, it should turn on the light ring when the headlights are turned on.

It doesn’t run off a single conductor. There are two power lines. One to power the outlet, and another for the light. Both share the third line, which is ground. That completes the circuit.

A test light looks like a clear pencil with an ice pick on one end and a wire with an aligator clip on the other. You clip the wire to a ground source. Then you probe the wire with the pick end. If the wire you are testing is a live power wire, the lightbulb in the center of the test light will turn on.

If your fuse has a 3 on it, it’s a 3A fuse. I’m pretty sure that the smallest fuse on this car is 5A. That’s one of the many reasons I don’t tap off an existing circuit. There are blank spaces in the fuse panel on the left side of the dash. You can get a wire that goes into a blank spot from Audi and then add the appropriate fuse. You would hen connect your red wire to the new wire from the fuse panel. Then it’s isolated from the rest of the car and the fuse is easily accessible. In that scenario you’d want to be rid of the inline fuse that’s in your kit. You don’t want two fuses on the same wire.

Honestly, I’d recommend you either add a circuit to a blank spot in the fuse panel or use a fuse tap. I personally don’t like fuse taps, but it’s definitely the easier way to go. And less likely to cause a problem for someone that isn’t familiar with wiring.

fairly certain that isnt an ILLUM wire (that should feed off the 12v)

my guess is its a switched 12v (meaning it goes on/off with the ignition)
but yes best way is just to test.
use a volt meter and go red/ brown then test grey/brown

Incorrect. Any lights that turn on with the headlights are part of the illumination circuit. See above.
And I’d still recommend a test light over a voltmeter or multimeter. Connect the wrong wires on the wrong multimeter setting and you could potentially break something. If you actually know how to use a multimeter correctly then it’s a good option. But for finding a power source, a test light is still the simplest and most foolproof way to go.

[morph2k4]

It doesn’t run off a single conductor. There are two power lines. One to power the outlet, and another for the light. Both share the third line, which is ground. That completes the circuit.

Thanks, this is super helpful. I didn't fully understand the shared negative/ground concept until I started reading about it now. My understanding of electricity is rudimentary at best. This makes sense now.

If your fuse has a 3 on it, it’s a 3A fuse. I’m pretty sure that the smallest fuse on this car is 5A. That’s one of the many reasons I don’t tap off an existing circuit. There are blank spaces in the fuse panel on the left side of the dash. You can get a wire that goes into a blank spot from Audi and then add the appropriate fuse. You would hen connect your red wire to the new wire from the fuse panel. Then it’s isolated from the rest of the car and the fuse is easily accessible. In that scenario you’d want to be rid of the inline fuse that’s in your kit. You don’t want two fuses on the same wire.

If my understanding is correct, I would need one of THESE, a 3 amp fuse that fits it, and any open slot on the fusebox that produces 12v? Then I would connect that wire to the live wire on the harness for the charger, and find a ground bolt or something to connect the negative wire on the harness to?

This might be a dumb question, but can I just hijack the cigarette lighter circuit by looking up it's slot and replacing it's fuse with a 3 amp one? That would let me avoid routing a new wire and finding/making a ground. The cig lighter would not be used after this anyway. Is there a reason this wouldn't work or might be problematic?

Honestly, I’d recommend you either add a circuit to a blank spot in the fuse panel or use a fuse tap. I personally don’t like fuse taps, but it’s definitely the easier way to go. And less likely to cause a problem for someone that isn’t familiar with wiring.

I'm having a little bit of trouble with the terminology. Are you talking about a wire with the little pincers that cut into an existing wire? It seems like the cables that plug into fuse slots are called fuse taps. Or am I misunderstanding something?


Thanks so much for your help! I'm nearly done with modeling the insert, so ready to tackle the wiring soon.

[DBFL]

If my understanding is correct, I would need one of THESE, a 3 amp fuse that fits it, and any open slot on the fusebox that produces 12v? Then I would connect that wire to the live wire on the harness for the charger, and find a ground bolt or something to connect the negative wire on the harness to?

This might be a dumb question, but can I just hijack the cigarette lighter circuit by looking up it's slot and replacing it's fuse with a 3 amp one? That would let me avoid routing a new wire and finding/making a ground. The cig lighter would not be used after this anyway. Is there a reason this wouldn't work or might be problematic?




I'm having a little bit of trouble with the terminology. Are you talking about a wire with the little pincers that cut into an existing wire? It seems like the cables that plug into fuse slots are called fuse taps. Or am I misunderstanding something?


Thanks so much for your help! I'm nearly done with modeling the insert, so ready to tackle the wiring soon.

That link is for a fuse tap. It uses an existing source to add a second circuit. If you open the panel on the left side of the dash, you’ll see three fuse banks. The middle and left should be switched power (controlled by the ignition). You’ll pull an existing fuse, add that device. There are two fuse ports on that. One should be marked for the original circuit. Put the original fuse in that port. Then put your 3A fuse in the other, cut out the fuse on your red wire, and then connect an extension wire from the red wire to the crimp connection on the fuse tap. Now you have a power source without messing with the car’s existing wiring. All that’s left is to ground it. The bolt by the fuse panel is a good spot.

[morph2k4]

That link is for a fuse tap. It uses an existing source to add a second circuit. If you open the panel on the left side of the dash, you’ll see three fuse banks. The middle and left should be switched power (controlled by the ignition). You’ll pull an existing fuse, add that device. There are two fuse ports on that. One should be marked for the original circuit. Put the original fuse in that port. Then put your 3A fuse in the other, cut out the fuse on your red wire, and then connect an extension wire from the red wire to the crimp connection on the fuse tap. Now you have a power source without messing with the car’s existing wiring. All that’s left is to ground it. The bolt by the fuse panel is a good spot.

Is there a reason my suggestion for just hijacking the original circuit for the cig lighter wouldn't work? I'll do what you said if I can't, but I really want to maximize simplicity on this. If I understand correctly, I can do all of this without running any wires by just replacing the cig lighter fuse with a 3a and connecting to it's power and ground wire where they are already to the ash tray.

[DBFL]

Is there a reason my suggestion for just hijacking the original circuit for the cig lighter wouldn't work? I'll do what you said if I can't, but I really want to maximize simplicity on this. If I understand correctly, I can do all of this without running any wires by just replacing the cig lighter fuse with a 3a and connecting to it's power and ground wire where they are already to the ash tray.

Yes, it will work if you can figure out which wire is power and which is ground. You do not want to change the factory fuse though. Audi doesn’t randomly choose a fuse size. They have a team of electrical engineers that design this stuff. You can add your wire to the power wire for the cigarette lighter, but in that scenario you’d want to leave the 3A fuse connected. The only problem here is that if the fuse blows you will have to take part of the dash/console apart to get to it. That’s one of the reasons I suggested running the wire to the fuse panel and placing the fuse there. You’re going to have to take apart a decent amount of the console to get the ash tray assembly out, so all that’s left to get the wire to the fuse panel are a few screws for the panel below the steering wheel.

[morph2k4]

Yes, it will work if you can figure out which wire is power and which is ground. You do not want to change the factory fuse though. Audi doesn’t randomly choose a fuse size. They have a team of electrical engineers that design this stuff. You can add your wire to the power wire for the cigarette lighter, but in that scenario you’d want to leave the 3A fuse connected. The only problem here is that if the fuse blows you will have to take part of the dash/console apart to get to it. That’s one of the reasons I suggested running the wire to the fuse panel and placing the fuse there. You’re going to have to take apart a decent amount of the console to get the ash tray assembly out, so all that’s left to get the wire to the fuse panel are a few screws for the panel below the steering wheel.

That makes sense. I'm going to load a home printed tray up first, and then order a more professionally printed part once I get the fit right, so I think I'll try the splice first since I'll be getting in there again anyway.

I guess the thing I don't fully understand is if amperage varies per slot on the fuse box, or if it's just a matter of how much power the device tries to draw. None of the guides I've seen indicate any amperage measurement when looking for an empty slot to use, so I'm kind of assuming they are all identical.

If the amperage is identical on every slot, and the cigarette lighter default fuse doesn't touch anything else, it should be identical to starting from scratch on an empty fuse slot, right? The only difference is that the output end of this fuse slot connects to wires that are already in the dash, and would otherwise be connected to nothing if I remove the ash tray assembly but leave the rest of that circuit undisturbed.

[DBFL]

That makes sense. I'm going to load a home printed tray up first, and then order a more professionally printed part once I get the fit right, so I think I'll try the splice first since I'll be getting in there again anyway.

I guess the thing I don't fully understand is if amperage varies per slot on the fuse box, or if it's just a matter of how much power the device tries to draw. None of the guides I've seen indicate any amperage measurement when looking for an empty slot to use, so I'm kind of assuming they are all identical.

If the amperage is identical on every slot, and the cigarette lighter default fuse doesn't touch anything else, it should be identical to starting from scratch on an empty fuse slot, right? The only difference is that the output end of this fuse slot connects to wires that are already in the dash, and would otherwise be connected to nothing if I remove the ash tray assembly but leave the rest of that circuit undisturbed.

You should probably use google and read up a bit on electricity. There’s a bit you’re not understanding, and it’s too much to try and explain it on a car forum.
But the short version is that the supply side of the fuse bank isn’t regulating amperage. That is what a fuse is for. A device will draw a certain amount of amperage. The amount differs from device to device. And a device will draw different amperage depending on usage/load. The fuse is the failsafe. If the device connected to it draws too much amperage, the fuse blows to protect the device and to keep the source from catching fire. If you use a fuse that is rated too low, it’ll blow when it shouldn’t. If you use a fuse that has too high of a rating, it won’t blow when a device draws too much current, resulting in damaged electronics and possibly fire.
At 3A it’s unlikely to cause a fire, but it’s still possible.

[Envy187]

You should probably use google and read up a bit on electricity. There’s a bit you’re not understanding, and it’s too much to try and explain it on a car forum.

Are YOU mainly using the ‘net for all of your great input to this thread, pal? Or do you happen to have a Ph.D in electrical engineering or something?

No disrespect; purely curious, as your knowledge is quite vast in this topic.


Sent from my iPhone using Audizine

[DBFL]

Are YOU mainly using the ‘net for all of your great input to this thread, pal? Or do you happen to have a Ph.D in electrical engineering or something?

No disrespect; purely curious, as your knowledge is quite vast in this topic.


Sent from my iPhone using Audizine

That comment wasn’t meant to be taken as me being an ass. This is just one of those topics that isn’t easily explained on a forum like this. I’m also not very good at teaching.
I know quite a bit about this subject. I’m not going to list all my credentials, but I’ve been working on electronics for many years.
As for how that applies here, I’ve done a lot of wiring in my S4. I have added OEM dash buttons to control the electronics that I have added. The buttons had to be reverse engineered to know how they work and how I would use them. I have an engine stop/start button that is now the power button for my radar detector; a hill hold cancellation button (European market only) for my radar mute; a front parking sensor button connected to a device set up as an electronic latching relay to toggle power for my laser jammer; an RS5 spoiler button that I just removed that controlled the electronic damping on the coil overs that I just replaced. I also changed my seats which causes 7 airbag related faults, so I made a harness that fools the car into thinking that the seat airbags are still installed and fully functional. I still have to finish some wiring to get rid of the remaining 5 faults. The parts were delivered a couple days ago, but I was prepping to go to the track this weekend so I haven’t time to finish that project yet. Also, every electronic item that I have added to my own car is on its own circuit with an appropriately sized fuse. I didn’t use any fuse taps. Instead, I used empty spots in different fuse blocks and added the appropriate wires to the fuse blocks. There’s probably more, but it’s 10pm and I’m exhausted from spending he entire day on the track.

[Envy187]

Damn, dude. Sounds to me like you should change your government name/legal name to Victor Frankenstein and call it a day!

Super impressive.


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[morph2k4]

You should probably use google and read up a bit on electricity. There’s a bit you’re not understanding, and it’s too much to try and explain it on a car forum.
But the short version is that the supply side of the fuse bank isn’t regulating amperage. That is what a fuse is for. A device will draw a certain amount of amperage. The amount differs from device to device. And a device will draw different amperage depending on usage/load. The fuse is the failsafe. If the device connected to it draws too much amperage, the fuse blows to protect the device and to keep the source from catching fire. If you use a fuse that is rated too low, it’ll blow when it shouldn’t. If you use a fuse that has too high of a rating, it won’t blow when a device draws too much current, resulting in damaged electronics and possibly fire.
At 3A it’s unlikely to cause a fire, but it’s still possible.

I hear you, but I think my explanation was actually spot on. Replacing a 5a fuse with a 3a fuse seems safe for everything except the fuse itself. If I'm adding the Qi charger, which is only supposed to draw 3 amps, and there is nothing else on that circuit, what part of this could possibly be unsafe?

[DBFL]

Damn, dude. Sounds to me like you should change your government name/legal name to Victor Frankenstein and call it a day!

Super impressive.


Sent from my iPhone using Audizine

Lol. Thanks.

I hear you, but I think my explanation was actually spot on. Replacing a 5a fuse with a 3a fuse seems safe for everything except the fuse itself. If I'm adding the Qi charger, which is only supposed to draw 3 amps, and there is nothing else on that circuit, what part of this could possibly be unsafe?

Are you sure that the cigarette lighter is on its own circuit by itself? I’ve never checked that, so it may be. In that case, yes you can do that. But that seems like the sort of thing that would share a circuit. The easiest way to tell would be to pull the fuse and see if everything else still works.

Edit: If the cigarettle lighter is indeed by itself on its own circuit, make sure you cap the third wire properly so it doesn’t touch anything metal and cause a spark.

[morph2k4]

Are you sure that the cigarette lighter is on its own circuit by itself? I’ve never checked that, so it may be. In that case, yes you can do that. But that seems like the sort of thing that would share a circuit. The easiest way to tell would be to pull the fuse and see if everything else still works.

Edit: If the cigarettle lighter is indeed by itself on its own circuit, make sure you cap the third wire properly so it doesn’t touch anything metal and cause a spark.

That's a fair point. The owners manual just lists that fuse as the cig lighter, but it's possible something else is on that circuit. That seems like all the more reason to just use the splice connectors onto the lines from the cig lighter. That way, I'm not risking damaging anything except the fuse in the Qi charger's cable.

It seems like a daunting proposition to validate that every single car system is still working if the cig lighter is disconnected.

[morph2k4]

The ashtray delete / charger carrier prototype is coming along nicely

[PeteRock]

Just my 2 cents as I already purchased and installed the inbay Wireless charging pad and then removed it because it charges slower than shit

It’s a cool concept to have wireless charging in the car but it’s not practical at all

Unless you drive long distances and don’t care about charging speed


Pete

[Envy187]

YIKES. Thanks for that, Pete.

Hopefully with the OP's homemade gizmo, he'll have better luck in that regard.

[hilmar2k]

Just my 2 cents as I already purchased and installed the inbay Wireless charging pad and then removed it because it charges slower than shit

It’s a cool concept to have wireless charging in the car but it’s not practical at all

Unless you drive long distances and don’t care about charging speed


Pete

Are you comparing speed to other wireless chargers, or charging plugged in? Wireless is definitely slower, but it is how I charge my phone about 95% of the time.

[CrownSeven]

Get this instead

Anker PowerWave Fast Wireless Car... https://www.amazon.com/dp/B07D9FYBMJ...p_mob_ap_share

[morph2k4]

Just my 2 cents as I already purchased and installed the inbay Wireless charging pad and then removed it because it charges slower than shit

It’s a cool concept to have wireless charging in the car but it’s not practical at all

Unless you drive long distances and don’t care about charging speed


Pete

How did you go about mounting it? Any details you'd be willing to share about your design, specifically how thick was the material in between the pad and the phone?

[PeteRock]

How did you go about mounting it? Any details you'd be willing to share about your design, specifically how thick was the material in between the pad and the phone?

My buddy’s audio shop did the install in my center console armrest area and there was no material in between the pad and the phone other than the pad that came with it....see below

It was so slow charging my iPhone that I had it removed after a couple of weeks

Which phone do you have?

IMG_1407.JPG


Pete

[morph2k4]

It was so slow charging my iPhone that I had it removed after a couple of weeks

Which phone do you have?

Pete

Very interesting. I've heard that the iphones wireless charge a lot slower than Samsung (I've got an S9), but wireless charging isn't lightning fast under any circumstances. I can get a full charge in about 2 hours, and I do spent 1-2 hours in the car every day, so it's a meaningful bump for me.

I will definitely report back once I get this going. I'd settle just for not losing charge from bluetooth streaming while I drive.

[PeteRock]

Very interesting. I've heard that the iphones wireless charge a lot slower than Samsung (I've got an S9), but wireless charging isn't lightning fast under any circumstances. I can get a full charge in about 2 hours, and I do spent 1-2 hours in the car every day, so it's a meaningful bump for me.

I will definitely report back once I get this going. I'd settle just for not losing charge from bluetooth streaming while I drive.

I think you’ll be fine with a Samsung phone....their wireless charging is way better than the iPhone’s

Good luck!


Pete

[Envy187]

Just like gaming on the Internet...Ethernet/hard-wiring into your system is VASTLY superior than trying to game on Wi-Fi/wireless.

Same deal with charging!


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[hilmar2k]

Just like gaming on the Internet...Ethernet/hard-wiring into your system is VASTLY superior than trying to game on Wi-Fi/wireless.

Same deal with charging!


Sent from my iPhone using Audizine

The opposite of that is also true, though. Just like with wifi, wireless charging is more convenient than wired. If you don't need the speed, wireless works great.

[Envy187]

The opposite of that is also true, though. Just like with wifi, wireless charging is more convenient than wired. If you don't need the speed, wireless works great.

Who in their right mind DOESN’T need speed, man? In today’s society, you can’t deny that it’s all about efficiency.

With the go-go-go nature of today’s world, you really think your average Joe wants to wait around twice as long to achieve the same result?

Be my guest...


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[pstonge]

Anyone have a link to the inbay unit? Thanks.

[PeteRock]

Anyone have a link to the inbay unit? Thanks.

https://www.uspmotorsports.com/Inbay...yABEgLZ8_D_BwE


Pete

[pstonge]

Thanks. Will this one work? I found it on the same site.

https://www.uspmotorsports.com/Inbay...-Coil-Kit.html

[PeteRock]

Thanks. Will this one work? I found it on the same site.

https://www.uspmotorsports.com/Inbay...-Coil-Kit.html

Looks like the same one to me so you should be good


Pete