Thank you for the thorough troubleshooting steps. 👍 I rewired my 67 mustang with the American Autowire kit and it helped me understand how all the wires were connected and what they actually did. I constantly revisit the wiring manual /schematic whenever I'm wanting to add accessories or troubleshoot electrical.
Hi Alex! Yes! You were right about a 50+ year old car gonna have wiring issues. Started a couple of weeks ago with a No crank, No start. Was a dead wire (broken) wire that went to the "S" terminal of 4 post solenoid. Didn't want to get into the harness so I put in a push button starter into dash. Works great until I rewire the car. NOW, coming home last night from the car cruise/show and no turn signals. Got running lights and brake lights though. Thanks for you video, It was an easy find now that I know it is a harness to harness connection. One male wire not plugged into harness plug, and One Yellow wire cut in two. Easy fix and you saved me from buying a turn signal switch etc etc. I will replace it after the car season this winter though. Thanks again Alex for your videos, time and teachings. Much appreciated sir. Cheers from Michigan.
Thanks for this! Although I couldn’t solve my issue (everything went as it should till I get to my wiring harness where I get constant power with or without break pedal input) it was the most informative and to the point video I found on UA-cam! Thanks a lot 🙏🏽
Ok here is one for ya. This is on a 65 coupe Break lights work, turn signals work, taillights work when I pull out the switch. However with the headlights on and I hit the break only the driver side goes out completely. The passenger side gets brighter.
Wrong bulb or the bulb socket is not making great contact? I would assume you've checked the obvious things but sometimes the simplest explanation tends to be the right one.
Hear your message loud and clear - ordered a wiring schematic from classic wiring and can’t wait to get it. I’ve recently traced down my dash cluster lights not working to a bad ground. I repaired that somehow broke my speedo cable trying to get it back on, but that’s a whole other issue. Now I’m noticing that my once functional brake lights do not work! The running lights work but when I step on the brake, I get no ‘additional’ brake light. What I don’t understand is if the brake light switch feeds the turn signal switch, I would think it only gets power when the brake is pressed? I know that’s not correct, but this one is confusing. Also wondering where the fix was with your car in the video. What solved the problem? I’m finding that when I have issues the first thing I’m thinking is, ‘Man, I hope Alf has a video on this!’ 😊
Oh awesome ya those laminated diagrams are great. So I should probably rephrase that statement. The brake light switch isn't responsible for supplying the main power source for the turn signal switch itself. However, the brake light circuit goes THROUGH the turn signal switch because that's where it splits into 2 circuits; left and right brake lights. I hope that makes sense. I hope that helps!
Alf, can I ask another question about this? I took my tester and checked the brake switch on the pedal exactly as you showed, and when I touched the first connection, it sparked pretty badly every time I touched that side of the switch. It was pretty bad. I touched the other side and got nothing while stepping on the pedal. So, should one side of the switch be constant power and then the other side lights up only when the pedal is pushed? I hate to blame the switch straight away and replace it, but the sparking on the constant power side was pretty scary! The rear blinkers and night time lights do work, and I checked that both have dual filament bulbs. Any thoughts or suggestions would be great - thanks again!
That would be correct. One side has power at all times and the other side gets the power once the pedal is pressed. If you're not getting that power transfer then you have a bad switch. As far as your sparking goes, are you accidentally touching your test light to the switch and a ground connection at the same time?
@@AlfsMustangGarage well that’s what I initially thought (that I was touching something else and grounding out the connection with the test light) so I repeated the procedure a few times and confirmed I wasn’t touching anything. It’s the only explanation though, I guess. I’ll try it again and see, but all I can hear is you in the video saying, ‘Don’t start out by just replacing the switch!’ I’m trying to make an honest effort to ‘learn’ what’s going on here, so I feel bad jumping straight to switch replacement. Thank you again for your help!
Well as long as you test it and have good reason to replace it, then thats how to figure things out. It's just people don't diagnose things anymore. They jump right to Facebook and get 100 wrong answers, 100 smart-ass answers and 1 correct one. 🤣
I had the exact problem you are showing here. Driver brake - hood power from the brake switch coming into the turn signal switch and hood coming down to the passenger side but not the driver. (Brand new turn signal switch) What was your solution ?
Took the car out 1st time in the dark and I have no brake lights when headlights are on, but when the headlights are off I have brake lights. I'm betting/hoping the tail light bulbs only have a single filament. I'll look at them after work.
@@AlfsMustangGarage So took of the lens to see if the bulb was right, it is. So I need to do some investigative work check fuses and the switches you mentioned in this video. I guess one advantage is being a 64 1/2 reverse lights were optional and this car does not have them. One less thing to worry about lol I'll keep you posted on what I find. One thing I noticed the socket for the bulbs has been changed out on both sides they have red and blue wires. Luckily they only go about 8 in and then switch back to the factory wires with the correct colored wires
@@AlfsMustangGarage So I got it figured out. The long and short of it is the tail light buckets and tail light sockets were replaced at some point. Off the back of the socket there is a red wire and a blue wire. Whoever did the work had splice them together with crimp butt connections. After messing around under the dash for about an hour I decided to cut the two wires and flip them around. And I'll be dang if it didn't work. Needless to say I put them back together with quick disconnect terminals just because.
I just replaced my turn signal switch. Brand new Scott Drake switch. Now I have nothing on the left. No brake. No turn signal. No Hazzard. Nothing on the left. They all worked before on the old switch. Are the colors for all these functions the same as the brake light in this video? Or does each function have its own colored wires?
Hey Alf - came back to this video as I am still struggling with brake light issues, but I’m getting closer to fixing the issue! (I think). I replaced my brake switch as well as turn signal switch, and I’m still having the same problem. Then I started wondering. I recently replaced my brake master cylinder with a dual bowl setup with an adjustable pushrod. When I push the brake pedal down, the brake switch doesn’t ‘compress’ and close the circuit. I’m wondering now with all these ‘new’ parts, is it possible I need to lengthen my pushrod on the master cylinder a turn or two? At rest, the pushrod looks to have a millimeter or two of slack between it and the contact head on the switch. It’s the only thing I can think of at this point, but like I said, pushing down on the brake pedal is clearly not compressing the brake switch and closing the circuit, so no brake lights. Would pay way more than a penny for your thoughts! Also, when are we going to see some Alf’s Mustang Garage merch!?
So lets go back to some basics if thats okay? If you jump the connection on the brake light switch, do the brake lights all work properly? If they do, that would confirm that the brake light switch is not making that connection. If you have a small amount of play in that pushrod and its adjustable, I would adjust that out and see what happens. What brand of brake light switch did you buy? Sometimes these aftermarket switches just don't work like the originals.
@@AlfsMustangGarage ye - absolutely! I'm trying to think of you and not just got to the FB forums and use my schematic and think it though before replacing parts, but my turn signal switch did have some frayed wires and someone rigged it by placing a rogue spring on one end of it and anchoring it to a mounting screw to help with auto-cancelling of the turn signals. Anyways..... To answer your question - yes! If I bypass the switch and jump the two wires together for the brake switch, the brake lights come on! I will adjust out the pushrod just a turn or two and see if that does the trick. Thank you again so much for your help with this... Forgot to mention - I ordered the brake switch from John's Mustang Parts here in Houston where I live. Seems to be a pretty 'standard issue' part. If there are better or worse places to buy the switch from, please let me know!
Oh ya Facebook is good but it's also hard because you get a lot of responses that just don't make sense. I think you definitely have it narrowed it down to the switch. Ya adjust the rod so there is no play and see if that changes. The switch is likely fine but if it still doesn't work after adjusting the pushrod, maybe try a different switch. This might be weird but I've used autozone switches before and had zero issues. But ya let me know how it goes.
@@AlfsMustangGarage well I tried to adjust the pushrod and it ended up popping out of the master cylinder and now I can't seem to get it to pop back in, which is resulting in an excess amount of 'play' in the pedal. I have brakes still, but I can't get the pushrod to seat back into the master cylinder.
I’m new to these classics. My question is that I have a 65 and when I press hard on the brake the taillights turn on. I was under the impression if I barely tap on the brake they should turn on. Is this accurate?
They should turn on when slightly pressing the pedal. You might have the brake light switch mounted on your master cylinder. They did that for a while on the early cars.
@@AlfsMustangGarage so I replaced the taillight switch and still nothing, but I did notice that the harness that connects to it that one terminal gives me 12v and the other doesn't
Hi there. I've got a 1969 Boss over here. I have no tail lights at all. Car had been sitting for several years and they worked when I parked it as far as I know. Replaced the bulbs, nothing. Some mice did live in it for a while, I am scared they may have chewed a wire. Have not checked any electrical. What do you think is usually the culprit here, where should I start. ? Thanks in advance!
That sounds like an awesome car! Umm honestly the first place I would start is buying one of those nice laminated color coded wiring diagrams for 69 from NPD. Well worth the expense when there are lots of unknown factors. But aside from that, you need to check to see if there is power getting to the bulb. If no, then you need to check if the headlight switch is sending the power down the circuit.
@@AlfsMustangGarage First off, thanks for the quick response. Ok so, here is the latest. I have brake lights on both sides, although one side seems to be brighter. Took her out for a drive, windshield wipers worked good at first then started getting slower and slower now barely moving, but still a little. But yes, I have brake lights, that part of the bulb is lighting up when I press the brake pedal. No tail lights though. Been researching switches. I understand the running back lights is supposed to be connected to the headlights switch. I've got headlights. I pulled up a diagram of the fuse box. I may replace all the fuses as the car has not been started in several years. I am unsure if there is a fuse for the back running lights, my research tells me not.
You're welcome. Ya it's hard to tackle these types of things because there could be several reasons why you could have this issue but ultimately when you have the diagram, it helps you narrow down your search. I try not to over think which is way easy to do but at the end of the day, you need a power and a ground and the bulb should work.
BRO PLEASE, my front left turn signals won’t work but everything else does. They stay on but won’t flash. Not the flash relays, replaced the turn signal switch. I cut the power cable to the left bulb and the front one started working! Re connected the wire to itself and both were working! Then it just stopped again
@@AlfsMustangGarage haha no worries. Its good to think about how the circuit works and go step by step until you identify the problem. I just started installing a painless wiring kit for my 66, and it was quite scary, but once you start, its not that bad. :)
Help me please!! I have a 68 similar looking to the 67 in this video. Issue is, my dash and tail lights will turn on for a split second when the headlight switch is pulled but then start to flicker. Headlights work consistently but the taillights do not. The brake lights also cease to work once the headlight switch is pulled as well. I’ve replaced the headlight switch and voltage regulator and went from wire to wire looking for a loose wire and can’t find the issue. Any and all recommendations are appreciated.
@@AlfsMustangGarage yes I’ve replaced all the bulbs on the exterior as well as in the dash cluster just to be on the safe side.. I also made it a point to make sure the sockets sit in the housing snug since it is how a lot of them ground. Next plan is to replace the turn signal switch with new wires and harness. But that part I have to wait on in the mail since no one has that part locally.
Thank you for the thorough troubleshooting steps. 👍 I rewired my 67 mustang with the American Autowire kit and it helped me understand how all the wires were connected and what they actually did. I constantly revisit the wiring manual /schematic whenever I'm wanting to add accessories or troubleshoot electrical.
That's awesome! It's nice to understand how it all works. Helps with troubleshooting for sure!
Hi Alex! Yes! You were right about a 50+ year old car gonna have wiring issues. Started a couple of weeks ago with a No crank, No start. Was a dead wire (broken) wire that went to the "S" terminal of 4 post solenoid. Didn't want to get into the harness so I put in a push button starter into dash. Works great until I rewire the car. NOW, coming home last night from the car cruise/show and no turn signals. Got running lights and brake lights though. Thanks for you video, It was an easy find now that I know it is a harness to harness connection. One male wire not plugged into harness plug, and One Yellow wire cut in two. Easy fix and you saved me from buying a turn signal switch etc etc. I will replace it after the car season this winter though. Thanks again Alex for your videos, time and teachings. Much appreciated sir. Cheers from Michigan.
I'm always happy to hear that these videos are helpful. Thanks again! Gosh is the car season coming to a end soon already!!!!
@@AlfsMustangGarage Now am replacing header gaskets on the 460. I got one inch of room to do that, lol But certainly doable.
Thanks for this! Although I couldn’t solve my issue (everything went as it should till I get to my wiring harness where I get constant power with or without break pedal input) it was the most informative and to the point video I found on UA-cam! Thanks a lot 🙏🏽
You're very welcome
THANK YOU for posting this! Found my brake light switch feed from the Light switch was pulled out and causing my no brake light issue.
Awesome! Good catch, glad I could help.
The orange gloves are back!!!!!
Oh ya!!
Ok here is one for ya. This is on a 65 coupe
Break lights work, turn signals work, taillights work when I pull out the switch. However with the headlights on and I hit the break only the driver side goes out completely. The passenger side gets brighter.
Wrong bulb or the bulb socket is not making great contact? I would assume you've checked the obvious things but sometimes the simplest explanation tends to be the right one.
Hear your message loud and clear - ordered a wiring schematic from classic wiring and can’t wait to get it. I’ve recently traced down my dash cluster lights not working to a bad ground. I repaired that somehow broke my speedo cable trying to get it back on, but that’s a whole other issue. Now I’m noticing that my once functional brake lights do not work! The running lights work but when I step on the brake, I get no ‘additional’ brake light. What I don’t understand is if the brake light switch feeds the turn signal switch, I would think it only gets power when the brake is pressed? I know that’s not correct, but this one is confusing. Also wondering where the fix was with your car in the video. What solved the problem? I’m finding that when I have issues the first thing I’m thinking is, ‘Man, I hope Alf has a video on this!’ 😊
Oh awesome ya those laminated diagrams are great. So I should probably rephrase that statement. The brake light switch isn't responsible for supplying the main power source for the turn signal switch itself. However, the brake light circuit goes THROUGH the turn signal switch because that's where it splits into 2 circuits; left and right brake lights. I hope that makes sense. I hope that helps!
Alf, can I ask another question about this? I took my tester and checked the brake switch on the pedal exactly as you showed, and when I touched the first connection, it sparked pretty badly every time I touched that side of the switch. It was pretty bad. I touched the other side and got nothing while stepping on the pedal. So, should one side of the switch be constant power and then the other side lights up only when the pedal is pushed? I hate to blame the switch straight away and replace it, but the sparking on the constant power side was pretty scary! The rear blinkers and night time lights do work, and I checked that both have dual filament bulbs. Any thoughts or suggestions would be great - thanks again!
That would be correct. One side has power at all times and the other side gets the power once the pedal is pressed. If you're not getting that power transfer then you have a bad switch. As far as your sparking goes, are you accidentally touching your test light to the switch and a ground connection at the same time?
@@AlfsMustangGarage well that’s what I initially thought (that I was touching something else and grounding out the connection with the test light) so I repeated the procedure a few times and confirmed I wasn’t touching anything. It’s the only explanation though, I guess. I’ll try it again and see, but all I can hear is you in the video saying, ‘Don’t start out by just replacing the switch!’ I’m trying to make an honest effort to ‘learn’ what’s going on here, so I feel bad jumping straight to switch replacement. Thank you again for your help!
Well as long as you test it and have good reason to replace it, then thats how to figure things out. It's just people don't diagnose things anymore. They jump right to Facebook and get 100 wrong answers, 100 smart-ass answers and 1 correct one. 🤣
I had the exact problem you are showing here. Driver brake - hood power from the brake switch coming into the turn signal switch and hood coming down to the passenger side but not the driver. (Brand new turn signal switch)
What was your solution ?
Turn signal switch fixed this one.
Took the car out 1st time in the dark and I have no brake lights when headlights are on, but when the headlights are off I have brake lights. I'm betting/hoping the tail light bulbs only have a single filament. I'll look at them after work.
Oh ya hopefully that's all it is. Keep us posted 👍
@@AlfsMustangGarage So took of the lens to see if the bulb was right, it is. So I need to do some investigative work check fuses and the switches you mentioned in this video. I guess one advantage is being a 64 1/2 reverse lights were optional and this car does not have them. One less thing to worry about lol I'll keep you posted on what I find. One thing I noticed the socket for the bulbs has been changed out on both sides they have red and blue wires. Luckily they only go about 8 in and then switch back to the factory wires with the correct colored wires
@@AlfsMustangGarage So I got it figured out. The long and short of it is the tail light buckets and tail light sockets were replaced at some point. Off the back of the socket there is a red wire and a blue wire. Whoever did the work had splice them together with crimp butt connections. After messing around under the dash for about an hour I decided to cut the two wires and flip them around. And I'll be dang if it didn't work. Needless to say I put them back together with quick disconnect terminals just because.
Awesome! Good to hear it wasn't too crazy!
I just replaced my turn signal switch. Brand new Scott Drake switch. Now I have nothing on the left. No brake. No turn signal. No Hazzard. Nothing on the left. They all worked before on the old switch. Are the colors for all these functions the same as the brake light in this video? Or does each function have its own colored wires?
Hey Alf - came back to this video as I am still struggling with brake light issues, but I’m getting closer to fixing the issue! (I think). I replaced my brake switch as well as turn signal switch, and I’m still having the same problem. Then I started wondering. I recently replaced my brake master cylinder with a dual bowl setup with an adjustable pushrod. When I push the brake pedal down, the brake switch doesn’t ‘compress’ and close the circuit. I’m wondering now with all these ‘new’ parts, is it possible I need to lengthen my pushrod on the master cylinder a turn or two? At rest, the pushrod looks to have a millimeter or two of slack between it and the contact head on the switch. It’s the only thing I can think of at this point, but like I said, pushing down on the brake pedal is clearly not compressing the brake switch and closing the circuit, so no brake lights. Would pay way more than a penny for your thoughts! Also, when are we going to see some Alf’s Mustang Garage merch!?
So lets go back to some basics if thats okay? If you jump the connection on the brake light switch, do the brake lights all work properly? If they do, that would confirm that the brake light switch is not making that connection. If you have a small amount of play in that pushrod and its adjustable, I would adjust that out and see what happens. What brand of brake light switch did you buy? Sometimes these aftermarket switches just don't work like the originals.
@@AlfsMustangGarage ye - absolutely! I'm trying to think of you and not just got to the FB forums and use my schematic and think it though before replacing parts, but my turn signal switch did have some frayed wires and someone rigged it by placing a rogue spring on one end of it and anchoring it to a mounting screw to help with auto-cancelling of the turn signals. Anyways..... To answer your question - yes! If I bypass the switch and jump the two wires together for the brake switch, the brake lights come on! I will adjust out the pushrod just a turn or two and see if that does the trick. Thank you again so much for your help with this... Forgot to mention - I ordered the brake switch from John's Mustang Parts here in Houston where I live. Seems to be a pretty 'standard issue' part. If there are better or worse places to buy the switch from, please let me know!
Oh ya Facebook is good but it's also hard because you get a lot of responses that just don't make sense. I think you definitely have it narrowed it down to the switch. Ya adjust the rod so there is no play and see if that changes. The switch is likely fine but if it still doesn't work after adjusting the pushrod, maybe try a different switch. This might be weird but I've used autozone switches before and had zero issues. But ya let me know how it goes.
@@AlfsMustangGarage well I tried to adjust the pushrod and it ended up popping out of the master cylinder and now I can't seem to get it to pop back in, which is resulting in an excess amount of 'play' in the pedal. I have brakes still, but I can't get the pushrod to seat back into the master cylinder.
Lol hang in there. Does your pushrod has the retaining clip on the end? Supposed to stay in the master cylinder once it's clicked in.
I’m new to these classics. My question is that I have a 65 and when I press hard on the brake the taillights turn on. I was under the impression if I barely tap on the brake they should turn on. Is this accurate?
They should turn on when slightly pressing the pedal. You might have the brake light switch mounted on your master cylinder. They did that for a while on the early cars.
@@AlfsMustangGarage ok thanks. Ima try to look that up and to see what’s going on
Sounds good 👍
@@AlfsMustangGarage so I replaced the taillight switch and still nothing, but I did notice that the harness that connects to it that one terminal gives me 12v and the other doesn't
Hi there. I've got a 1969 Boss over here. I have no tail lights at all. Car had been sitting for several years and they worked when I parked it as far as I know. Replaced the bulbs, nothing. Some mice did live in it for a while, I am scared they may have chewed a wire. Have not checked any electrical. What do you think is usually the culprit here, where should I start. ? Thanks in advance!
That sounds like an awesome car! Umm honestly the first place I would start is buying one of those nice laminated color coded wiring diagrams for 69 from NPD. Well worth the expense when there are lots of unknown factors. But aside from that, you need to check to see if there is power getting to the bulb. If no, then you need to check if the headlight switch is sending the power down the circuit.
@@AlfsMustangGarage First off, thanks for the quick response. Ok so, here is the latest. I have brake lights on both sides, although one side seems to be brighter. Took her out for a drive, windshield wipers worked good at first then started getting slower and slower now barely moving, but still a little. But yes, I have brake lights, that part of the bulb is lighting up when I press the brake pedal. No tail lights though. Been researching switches. I understand the running back lights is supposed to be connected to the headlights switch. I've got headlights. I pulled up a diagram of the fuse box. I may replace all the fuses as the car has not been started in several years. I am unsure if there is a fuse for the back running lights, my research tells me not.
You're welcome. Ya it's hard to tackle these types of things because there could be several reasons why you could have this issue but ultimately when you have the diagram, it helps you narrow down your search. I try not to over think which is way easy to do but at the end of the day, you need a power and a ground and the bulb should work.
BRO PLEASE, my front left turn signals won’t work but everything else does. They stay on but won’t flash. Not the flash relays, replaced the turn signal switch. I cut the power cable to the left bulb and the front one started working! Re connected the wire to itself and both were working! Then it just stopped again
running nose? hahaha love the videos! :)
Oh my god yes! I didn't realize how bad I was till I was editing. Lol too much work to edit all 125 of those sniffles!
@@AlfsMustangGarage haha no worries. Its good to think about how the circuit works and go step by step until you identify the problem. I just started installing a painless wiring kit for my 66, and it was quite scary, but once you start, its not that bad. :)
Oh ya that's awesome! I love the new modern wiring kits. It seems overwhelming but in reality, it's not too bad.
Help me please!! I have a 68 similar looking to the 67 in this video. Issue is, my dash and tail lights will turn on for a split second when the headlight switch is pulled but then start to flicker. Headlights work consistently but the taillights do not. The brake lights also cease to work once the headlight switch is pulled as well. I’ve replaced the headlight switch and voltage regulator and went from wire to wire looking for a loose wire and can’t find the issue. Any and all recommendations are appreciated.
I assume you've checked the bulbs and the bulb sockets?
@@AlfsMustangGarage yes I’ve replaced all the bulbs on the exterior as well as in the dash cluster just to be on the safe side.. I also made it a point to make sure the sockets sit in the housing snug since it is how a lot of them ground. Next plan is to replace the turn signal switch with new wires and harness. But that part I have to wait on in the mail since no one has that part locally.
Do you have a good wiring diagram?
@@AlfsMustangGarage I’ve been using the one from classic car wiring. It’s the most easy to read diagram I’ve found .
Very good, I hope you get it figured out
there isnt any for a 68 XR 7 cougar. on the page