I have a Nissan that has rear deck 6x9 speakers hooked up to a factory amplifier. When I had my new 10.1" Android double DIN touchscreen head unit, amplifier, and subwoofer professionally installed the rear speakers were not hooked up. I bought a second amplifier and cut the factory 6x9 wires to tap into the speakers and bypass the factory amp. One speaker has yellow and blue wires and the other has brown and red. We all know that red is positive, but I needed to be certain that this is so in this case. So I used your method and was able to figure out the polarity of each speaker. For anyone with Nissan rear deck 6x9 speakers here's the polarity: Brown: Negative Red: Positive Blue: Negative Yellow: Positive Your RUclips video prevented me from damaging my car's audio equipment. So you know that I had to hit those Like and Subscribe buttons. I wish you the best of luck with your RUclips channel. 😁
Interesting technique for sure another easy and mindless way to find out your positive to positive and negative clarity is to simply get out a 12 volt multi meter and set the meter to 12 Volts DC, connect your negative to your negative terminal and your positive to your positive terminal, if your positive terminal is on your positive wire, it should read that you’re getting Anywhere from 7 to 12 Volts.
NIce video. I suggest using a AA battery first since its just 1.5V its much safer than 9v. if you cant clearly see the speaker movement then move up to 3v etc and move your way up to 9v.
Great video! I was wondering how I could test polarity on 2 speakers wired in series. My 4Runner’s 2 rear channels are wired in series. Each rear channel has 2 speakers
This is a great video to identify the polarity on the actual speaker only, I need to identify the actual polarity of the cables coming from the stereo as there is no speaker there and the speaker I need to fit is a very small tweeter which I do know the polarity of, however I do not know which door wire is the positive to connect the positive side of the tweeter to... and getting the head out is going to be a pain to examine the rear of the unit to see what's what at that point. Can you help please? Subscription promised. Thanks
@@carstereochick Its a 2005 Fiat Ducato motorhome. The very tiny tweeter that was removed was no longer working and I still have that, but it came with the vehicle and its very old, yes the tiny plug that goes into the tweeter I still have, but there are no polarity markings on it at all. I just need to work out which door wire is the positive so I can replace a new larger tweeter,
Generally most manufacturers use clip side (wherever the tab is to release the connection) as positive. Is there a small capacitor on the tweeter? If so, that is typically soldered to the positive side. Do you see a capacitor on the back of that tweeter? If all else fails, you may want to buy this $12 tool that includes test tones to determine polarity - amzn.to/43xCSO1
Yeah, for tweeters you typically have to look at the tweeter itself. Most manufacturers use clip side (wherever the tab is to release the connection) as positive. If there is a cap on the back of the tweeter that is normally soldered to the positive side. Or use a simple and inexpensive audio testing tool like this: amzn.to/3xAU4qH
There's a few ways you could do it. If you can see the speaker in the door/rear shelf and you're probing the wires either from behind the factory head unit or at the stock amplifier (like if you're trying to wire up a head unit and the harness is cut or if you're trying to decipher speaker color wires to do a stock amplifier bypass for example) you can probe/pop those lines from behind the head unit or at the amp and watch whether the speaker is moving in or out. Or if you remove the door panel, remove the speaker, take note of how the connector is seated to the speaker when you remove it (example - brown wire on top, green on the bottom) then you can either take the speaker out and test it or while it's still connected to the harness in the door, strip back the wires back that are going to the speaker and probe/test it right there.
thanks, but does it hurt to do this if the speaker wire has a capacitor on it? Usually they connect the capacitor to the positive wire, but some imported stuff can be a bit of a hit and miss.
So you know the polarity of your speaker terminals , not of the wires unless well i don't know hoping they are connected correctly ? l really am not sure. 50% problem solved , thank you . Nothings easy .
That's good for a speaker when you can see how the cone behaves. But what about a sealed speaker where you can't see the cone because the grill doesn't come off? I have a Monsoon speaker that connects to a subwoofer but the red tag came off the wire that identifies it as positive. The speakers are sealed and I can't see the cone.
Is this in a car? Usually there is at least a speaker grille that you can shine a flashlight through and see. If it's not visible you may want to buy a phase tester on Amazon for $14. amzn.to/3RpbXPs
@@carstereochick It's one of a pair of Monsoon speakers for a computer that comes with a subwoofer. They're pretty dated and someone left them behind at my job and I just wanted to identify the + / - wires in case someone wanted them. When touching the wire leads to a battery, I just hear what sounds like static for a brief second. They are flat speakers and don't use traditional cones. I'll probably just put them in a pile for someone to pick up and figure out on their own. I was just looking to make it easier.
Hello - just a head unit install? Usually that is only 18 gauge, but sometimes you will see 14 or 16 used on theignition and ground wires for models that have a high powered internal amplifier.
Even a double AA battery would work, it would be enough to see it move, but it would only be a faint audible pop so just keep that in mind if you're trying to decode OEM speaker wiring and hear/pin point which pair of speaker wires you're on then you might want a little more.
Same concept, but the tweeter movement will be very slight and use a lower voltage on the tweeter. Like a 3 volt battery would be better to use on the tweeter, don't use 9 volts. Usually you can tell by physically looking at the terminals. The bigger one is always positive. Can you see both drivers move? Or can you easily remove them to examine them?
If you follow the 9 volt battery demonstration then you have a dead battery, a bad wire, or a bad speaker something not conducting electricity provided you have electricity. Switch batteries and test again. Also you can perform your test on another speaker. If the problem follows you then it is not your battery. That should give you enough info to determine where the fault is. I assume you have removed the wires from the head unit. Remember you are only testing the Speaker, not the wiring harness from the head unit.
Assuming you just probe the wires with the door panel off you can do a visual assessment of the speaker to identify which one is positive and negative.
So if you are replacing door speakers for example and need to check the polarity, you can literally cut off the factory connector while still connected to the factory speaker and test the bare leads coming off that factory connector. Then solder in new speaker wire to the OEM wires. If you've got no factory speaker to check against, you may want to invest in a basic polarity test tone tool FH-168.
So you started this video talking about factory wires and not know which is which, well. You never showed us how to tell which is which on the factory wires. I’m working on a truck that’s already had the speakers taken out. Now I don’t know which is positive or negative.
It’s just a 9 volt battery. Ever measure voltage through speaker level from a factory or aftermarket head unit? Most send anywhere from 4 to 16 volts through speaker level. Won’t harm them and no sparks 😉
@@carstereochick yes I do it with my 12 volt drill battery daily but you can only do it once or twice before you can damage speaker.or I use my fluke volt meter.but the drill battery works on my milwaukee drill
In my 20+ years experience never damaged a speaker from this, but 12 volts might be a bit much for some speakers. Many aftermarket head units put out 8-9 volts clean signal through their built in amplifier and a lot of newer stock stereos put out more voltage than this through the stock speaker lines. Example- 2020 Grand Cherokee non amplified with no load there is 5 volts going through the speaker lines. Once you actually put a load on it and turn it up you have more. Some stock stereo systems are piping through as much as 30 volts (usually in the premium sound models). You could use a smaller battery too like a D which is only 1.5 volts for same test. OR you could use Metra's convenient All-in-One tester with tone generator which includes a (*gasp!) 9 volt speaker tester: theinstallbay.com/product/IBR68.
This method only works if you can see the speaker In your car If you can't see the speaker you won't know the direction it's moving. When you test with the battery.
Yes, this is true. However in a lot of cases if you shine a bright LED work light through the door grille, you can still usually see the movement. Sometimes this requires 2 people, one to look and one to test the wires. If you can't do it that way, in that case you have to spend some money on more sophisticated testing equipment. But not much. This would do the trick: amzn.to/43xCSO1
Thank you :) You could use a tool with a test track like this - amzn.to/3zbHA7e or you could buy an all in one tool like this - www.mobilesolutions-usa.com/product-page/pt-9aplus-kit
Most stock speaker terminals are not marked, they’ll have a locking plastic connector and if you’re cutting that off or tapping into it to install aftermarket this test will help you figure out what’s positive and negative before you install your aftermarket speakers. Also, keep in mind, what you find in the door doesn’t necessarily always match what’s behind the head unit 👍
I don't think you watched it. It's quite simple. Take a battery, hook up your speaker wires to the positive and negative lead on the battery. In the car you are working on, say for example you're trying to bypass a stock amp that has failed and you're installing an aftermarket radio and need to identify each of your speakers leads. Typically in that example you'll find twisted pair wire at the stock amp which will help you determine the pairs of speakers. You can probe the wires with the battery tester to listen for which speaker is popping to identify your different channels. Then (usually with a buddy's assistance) you can probe the wires again and see if the speaker is moving out or in to determine polarity. And if you're installing aftermarket speakers in a door and you can't tell my looking at the terminal what's positive or negative, it's pretty easy to perform this test at the speaker terminal. You can dislike, but it's a simple test a lot of professionals use. In fact, Metra makes a cool combo device that includes this tester plus a frequency tone generator. They call it an All In One Tester IBR68. It's quite handy if you actually work on cars and install aftermarket equipment on a regular basis.
@carstereochick sorry for being an ass, but the battery thing isn't reliable.... I was trying to figure out which factory speaker wires were positive and negative. They can only be plugged in one way so I used the battery test on the factory speaker to try to figure it out. I seen two different videos. One says use a AA, and others say use a 9Volt. I tried both ways with the positives and negatives on each battery going to the same terminals on the speaker. And had two different outcomes. One will pop the speaker out and the other battery will sink the speaker.
If you need to check polarity and you can't see the speaker movement, you're gonna need tools. You can spend $12 on Amazon for a "Automotive Speaker Polarity Tester Phasemeter Tool" that includes a test track --> amzn.to/44up7QK
Yes, depending on what you're dealing with - whether you're trying to bypass a factory amp that's failed or install aftermarket speakers using factory wiring or trying to verify polarity for adding an aftermarket amp/sub using a LOC - then you would need to strip wiring back a bit to probe and test :)
@@carstereochick I still think you are not answering the question. The questions pertain to the polarity of the wires supplying the speaker, not the polarity of the speaker terminals. My wires to the speaker are both gold, not red and black. How can I use a multimeter to test which of the wires supplying the speaker should be attached to the positive terminal and which to the negative terminal?
Hi I just found your video and channel quick question what if the speaker is inside the car door I can't see it whether it's going in or out so if you have an answer for that I'll subscribe ring the bell and share
Hi Gabriel - great question. It does get tricky if the speaker is inside a door panel where even if you shine a light through the grille, you still can't see what it's doing. For that we use a basic test tool (part # FH-168) which includes specific test tracks. You can buy one on Amazon for about $12.
I have a Nissan that has rear deck 6x9 speakers hooked up to a factory amplifier. When I had my new 10.1" Android double DIN touchscreen head unit, amplifier, and subwoofer professionally installed the rear speakers were not hooked up. I bought a second amplifier and cut the factory 6x9 wires to tap into the speakers and bypass the factory amp. One speaker has yellow and blue wires and the other has brown and red. We all know that red is positive, but I needed to be certain that this is so in this case. So I used your method and was able to figure out the polarity of each speaker. For anyone with Nissan rear deck 6x9 speakers here's the polarity:
Brown: Negative
Red: Positive
Blue: Negative
Yellow: Positive
Your RUclips video prevented me from damaging my car's audio equipment. So you know that I had to hit those Like and Subscribe buttons. I wish you the best of luck with your RUclips channel. 😁
Putting theory in action simply enough! Helped me wire up my new Corolla speakers correctly when I was seriously lost. Thanks!
I just tried this on some old speakers that had no terminal markings, thank you!!
You’re welcome! 🙂
Interesting technique for sure another easy and mindless way to find out your positive to positive and negative clarity is to simply get out a 12 volt multi meter and set the meter to 12 Volts DC, connect your negative to your negative terminal and your positive to your positive terminal, if your positive terminal is on your positive wire, it should read that you’re getting Anywhere from 7 to 12 Volts.
@Eurospec73
How can a speaker by itself produce 7 to 12 volts for a multimeter to be able to read that.
Thanks, Short and to the point. I just wired new speakers for my Toyota Highlander.
NIce video. I suggest using a AA battery first since its just 1.5V its much safer than 9v. if you cant clearly see the speaker movement then move up to 3v etc and move your way up to 9v.
Thanks for the help, helped me check if a wire was actually functional from head unit to way back of a jeep.
You're welcome! I'm so glad you found it helpful.
Love this!
Been a mechanic for the past 40 years, specializing in drivability and electrical.
This is so simple!
Thank you!
So happy I could help!!
Keep them Coming !!!! I enjoy making Little Short How-To Videos for friends to Enjoy and Assist then on there way ...
Thanks Chris! I love your enthusiasm and support! It's awesome and truly appreciated. We will keep them coming :)
@@carstereochick coming from 1 Stereo Shop Owner to another !!! I just try to Educate Folks much as Possible ....
Awesome! What's the name of your shop? Where are you located?
What about the wire how to know which wire is positive & which negagive
What a great trick. Thank you so much! This saved me a headache.
You're welcome! I'm so glad you found it helpful.
Thank you!
Simple and concise. 🙂
Thank you for such a simple tip. Lovely.
Thank you, from Philippines
Great video! I was wondering how I could test polarity on 2 speakers wired in series. My 4Runner’s 2 rear channels are wired in series. Each rear channel has 2 speakers
This is a great video to identify the polarity on the actual speaker only, I need to identify the actual polarity of the cables coming from the stereo as there is no speaker there and the speaker I need to fit is a very small tweeter which I do know the polarity of, however I do not know which door wire is the positive to connect the positive side of the tweeter to... and getting the head out is going to be a pain to examine the rear of the unit to see what's what at that point. Can you help please? Subscription promised. Thanks
What’s the year, make and model? Do you have the factory speaker that was removed? And is the factory speaker plug still intact?
@@carstereochick Its a 2005 Fiat Ducato motorhome. The very tiny tweeter that was removed was no longer working and I still have that, but it came with the vehicle and its very old, yes the tiny plug that goes into the tweeter I still have, but there are no polarity markings on it at all. I just need to work out which door wire is the positive so I can replace a new larger tweeter,
Generally most manufacturers use clip side (wherever the tab is to release the connection) as positive. Is there a small capacitor on the tweeter? If so, that is typically soldered to the positive side. Do you see a capacitor on the back of that tweeter? If all else fails, you may want to buy this $12 tool that includes test tones to determine polarity - amzn.to/43xCSO1
@@carstereochick Thank you I got my answer now, yes there is a capacitor and I now know that is the positive side.
It works for speakers large enough to see the cone move, but not for something like tweeter, where you can't.
Yeah, for tweeters you typically have to look at the tweeter itself. Most manufacturers use clip side (wherever the tab is to release the connection) as positive. If there is a cap on the back of the tweeter that is normally soldered to the positive side. Or use a simple and inexpensive audio testing tool like this: amzn.to/3xAU4qH
Gracias! Super useful and concise!
How do you test the car wiring for polarity?
There's a few ways you could do it. If you can see the speaker in the door/rear shelf and you're probing the wires either from behind the factory head unit or at the stock amplifier (like if you're trying to wire up a head unit and the harness is cut or if you're trying to decipher speaker color wires to do a stock amplifier bypass for example) you can probe/pop those lines from behind the head unit or at the amp and watch whether the speaker is moving in or out. Or if you remove the door panel, remove the speaker, take note of how the connector is seated to the speaker when you remove it (example - brown wire on top, green on the bottom) then you can either take the speaker out and test it or while it's still connected to the harness in the door, strip back the wires back that are going to the speaker and probe/test it right there.
thank you!
Too easy, thank YOU
You're welcome!
This helped me install my new head unit correctly. Thanks!!!
Excellent! Glad I could help 👍
How can you do it if all you can see is the wire and cant see the speaker?
Thanks lovely lady I just learned from you.
You’re welcome ☺️
thanks, but does it hurt to do this if the speaker wire has a capacitor on it? Usually they connect the capacitor to the positive wire, but some imported stuff can be a bit of a hit and miss.
Usually on tweeters cap side is positive. Also clip side on the OEM connection is usually positive. I hope that helps.
Would a blown speaker/subwoofer still move like this?
Unfortunately no.
You rule!
Car stereo wow great job.
Thanks! 👍
So you know the polarity of your speaker terminals , not of the wires unless well i don't know hoping they are connected correctly ? l really am not sure. 50% problem solved , thank you . Nothings easy .
if they’re wired backwards it would still be the same affect, you’d just reverse it at the speakers would change the polarity
@@SoyChukii Thumbs up, thanks for the reply
That's good for a speaker when you can see how the cone behaves. But what about a sealed speaker where you can't see the cone because the grill doesn't come off? I have a Monsoon speaker that connects to a subwoofer but the red tag came off the wire that identifies it as positive. The speakers are sealed and I can't see the cone.
Is this in a car? Usually there is at least a speaker grille that you can shine a flashlight through and see. If it's not visible you may want to buy a phase tester on Amazon for $14.
amzn.to/3RpbXPs
@@carstereochick It's one of a pair of Monsoon speakers for a computer that comes with a subwoofer. They're pretty dated and someone left them behind at my job and I just wanted to identify the + / - wires in case someone wanted them. When touching the wire leads to a battery, I just hear what sounds like static for a brief second. They are flat speakers and don't use traditional cones. I'll probably just put them in a pile for someone to pick up and figure out on their own. I was just looking to make it easier.
Thanks! Very helpful!
My pleasure, happy to hear it :)
Madam , which wire gauge suitable for wiring head unit to speaker? 18 or 16 ?
Hello - just a head unit install? Usually that is only 18 gauge, but sometimes you will see 14 or 16 used on theignition and ground wires for models that have a high powered internal amplifier.
How would you do this test with transducer speaker (aka exciter)?
So sorry, but I have no idea as I haven't run into that in a car audio application.
Whats the minimum voltage we can put on to test the speaker polarity
Even a double AA battery would work, it would be enough to see it move, but it would only be a faint audible pop so just keep that in mind if you're trying to decode OEM speaker wiring and hear/pin point which pair of speaker wires you're on then you might want a little more.
@@carstereochick this would be very helpful mam
Speaker pushes out (+)
Speaker pushes in (-)
Nice but the polarity from the radio.. the speaker usually has the polarity on it..
How to check 2way speaker's (woofer & tweeter) polarity ?
Same concept, but the tweeter movement will be very slight and use a lower voltage on the tweeter. Like a 3 volt battery would be better to use on the tweeter, don't use 9 volts. Usually you can tell by physically looking at the terminals. The bigger one is always positive. Can you see both drivers move? Or can you easily remove them to examine them?
@@carstereochick
Thanks
Well, when I plug my door speakers up, they don’t move at all, so how can I tell?
If you follow the 9 volt battery demonstration then you have a dead battery, a bad wire, or a bad speaker something not conducting electricity provided you have electricity. Switch batteries and test again. Also you can perform your test on another speaker. If the problem follows you then it is not your battery. That should give you enough info to determine where the fault is. I assume you have removed the wires from the head unit. Remember you are only testing the Speaker, not the wiring harness from the head unit.
How do you check the polarity of the wires in the car?
Assuming you just probe the wires with the door panel off you can do a visual assessment of the speaker to identify which one is positive and negative.
@@carstereochick Perform a continuity check with a volt meter.
Wait that tells me the polarity of the speaker, how do I test the wires coming out of the car door?
So if you are replacing door speakers for example and need to check the polarity, you can literally cut off the factory connector while still connected to the factory speaker and test the bare leads coming off that factory connector. Then solder in new speaker wire to the OEM wires. If you've got no factory speaker to check against, you may want to invest in a basic polarity test tone tool FH-168.
@@carstereochick Thanks.
Hello, that is helpful but realistically cars speaker wires are usually random colors with a different color stripe.
Yup so if you probe the random colored wires and watch what the speaker does you can identify what's positive and negative.
@@carstereochick Yeah, that's something I learned fairly recently. Thanks for sharing this video, it was of some help to me.
So you started this video talking about factory wires and not know which is which, well. You never showed us how to tell which is which on the factory wires. I’m working on a truck that’s already had the speakers taken out. Now I don’t know which is positive or negative.
But won't those 2 wires touch n spark on battery tester?
It’s just a 9 volt battery. Ever measure voltage through speaker level from a factory or aftermarket head unit? Most send anywhere from 4 to 16 volts through speaker level. Won’t harm them and no sparks 😉
@@carstereochick yes I do it with my 12 volt drill battery daily but you can only do it once or twice before you can damage speaker.or I use my fluke volt meter.but the drill battery works on my milwaukee drill
In my 20+ years experience never damaged a speaker from this, but 12 volts might be a bit much for some speakers. Many aftermarket head units put out 8-9 volts clean signal through their built in amplifier and a lot of newer stock stereos put out more voltage than this through the stock speaker lines. Example- 2020 Grand Cherokee non amplified with no load there is 5 volts going through the speaker lines. Once you actually put a load on it and turn it up you have more. Some stock stereo systems are piping through as much as 30 volts (usually in the premium sound models). You could use a smaller battery too like a D which is only 1.5 volts for same test. OR you could use Metra's convenient All-in-One tester with tone generator which includes a (*gasp!) 9 volt speaker tester: theinstallbay.com/product/IBR68.
This method only works if you can see the speaker In your car If you can't see the speaker you won't know the direction it's moving. When you test with the battery.
Yes, this is true. However in a lot of cases if you shine a bright LED work light through the door grille, you can still usually see the movement. Sometimes this requires 2 people, one to look and one to test the wires. If you can't do it that way, in that case you have to spend some money on more sophisticated testing equipment. But not much. This would do the trick: amzn.to/43xCSO1
Love those eyes Girl, I dont want to pull all my speakers out so how do, I check for + and - if I can't see the speaker?
Thank you :) You could use a tool with a test track like this - amzn.to/3zbHA7e or you could buy an all in one tool like this - www.mobilesolutions-usa.com/product-page/pt-9aplus-kit
Great
Thank you 🙏
This gives you the polarity of the speaker not of the wire itself
Yes, but if you can see the speaker is doing then you know what the wires are that you're probing/testing.
99% of the spakers have mark for + and Negative. How to test the speakers wires that came from the Radio without removing the Radio?
Most stock speaker terminals are not marked, they’ll have a locking plastic connector and if you’re cutting that off or tapping into it to install aftermarket this test will help you figure out what’s positive and negative before you install your aftermarket speakers. Also, keep in mind, what you find in the door doesn’t necessarily always match what’s behind the head unit 👍
Useless video. She doesn't show what wires are connected to the battery or how it relates to the vehicles speaker wires. DISLIKE
I don't think you watched it. It's quite simple. Take a battery, hook up your speaker wires to the positive and negative lead on the battery. In the car you are working on, say for example you're trying to bypass a stock amp that has failed and you're installing an aftermarket radio and need to identify each of your speakers leads. Typically in that example you'll find twisted pair wire at the stock amp which will help you determine the pairs of speakers. You can probe the wires with the battery tester to listen for which speaker is popping to identify your different channels. Then (usually with a buddy's assistance) you can probe the wires again and see if the speaker is moving out or in to determine polarity.
And if you're installing aftermarket speakers in a door and you can't tell my looking at the terminal what's positive or negative, it's pretty easy to perform this test at the speaker terminal. You can dislike, but it's a simple test a lot of professionals use. In fact, Metra makes a cool combo device that includes this tester plus a frequency tone generator. They call it an All In One Tester IBR68. It's quite handy if you actually work on cars and install aftermarket equipment on a regular basis.
@carstereochick sorry for being an ass, but the battery thing isn't reliable.... I was trying to figure out which factory speaker wires were positive and negative. They can only be plugged in one way so I used the battery test on the factory speaker to try to figure it out. I seen two different videos. One says use a AA, and others say use a 9Volt. I tried both ways with the positives and negatives on each battery going to the same terminals on the speaker. And had two different outcomes. One will pop the speaker out and the other battery will sink the speaker.
that's useless if you cant see the speaker
If you need to check polarity and you can't see the speaker movement, you're gonna need tools. You can spend $12 on Amazon for a "Automotive Speaker Polarity Tester Phasemeter Tool" that includes a test track --> amzn.to/44up7QK
do you mean i have to strip the factory speaker wire to perform this test? my goal is to determine the polarity of the wires on my car😊
Yes, depending on what you're dealing with - whether you're trying to bypass a factory amp that's failed or install aftermarket speakers using factory wiring or trying to verify polarity for adding an aftermarket amp/sub using a LOC - then you would need to strip wiring back a bit to probe and test :)
@@carstereochick I still think you are not answering the question. The questions pertain to the polarity of the wires supplying the speaker, not the polarity of the speaker terminals. My wires to the speaker are both gold, not red and black. How can I use a multimeter to test which of the wires supplying the speaker should be attached to the positive terminal and which to the negative terminal?
Hi I just found your video and channel quick question what if the speaker is inside the car door I can't see it whether it's going in or out so if you have an answer for that I'll subscribe ring the bell and share
Hi Gabriel - great question. It does get tricky if the speaker is inside a door panel where even if you shine a light through the grille, you still can't see what it's doing. For that we use a basic test tool (part # FH-168) which includes specific test tracks. You can buy one on Amazon for about $12.