There is a very large class of people that own 65/66 Mustangs that, as far as I can tell, anyway, have been, for the most part, ignored entirely. They don't really want that 100 pt. show car that is so nice and was soooo expensive that they're afraid to drive it, they also don't want to make their car capable of achieving warp factor three. They just want this car that they dearly love to be able to cruise around smoothly and reliably, without having it dump them out on the side of the road or have it start making weird noises or belching out big clouds of funky-smelling smoke. And I think, truth be told, that this is by far the largest class of Mustang owners. They take their car to some technician when what they actually need is a mechanic, and this, frequently, does not work out very well at all for the owner. They don't want to re-engineer the entire car, they just want someone to fix what broke. These are the people that I am trying help out with this blog. Some problems require a little bit of back and forth, as in, "Try this." "I tried that and it didn't change anything."
" Oh. well, you probably need to try that." " I tried that and it helped, but it still isn't quite right." "Now you need to try this...." If you go to http://www.allfordmustangs.com/ and then go to the classics forums, you will be able to do that with a pretty hefty gathering of some very knowledgeable people that also happen to be very friendly. None of that ridiculous one-upmanship, no flaming or abuse, none of that stuff. Just good, solid advice from people that know what they are talking about.

Saturday, March 29, 2008

Turn signals

Here is the wiring diagram for just the turn signals. How they work is power comes from the ignition switch to the signal flasher. From the signal flasher it goes into the turn signal switch and from there to the appropriate stuff on the left or right-hand side of the car. On a 66, or a 65 with the GT package, or pony interior, if only one indicator isn't working, like the left dash indicator for example, that is normally the bulb is burned out. Sometimes it will be a socket or a wire problem, but normally the bulb itself. On a 65, there is only one dash indicator light for both turn signals. That bulb has two wires going to it, instead of only one, like a 66. If an entire side isn't working, that will normally be a turn signal switch problem. If nothing works at all, start at the signal flasher to make sure power is both getting there and leaving there. If yes, you probably have a break of some sort in the wire that goes from the flasher to the turn signal switch. If the appropriate lights come on, but just don't flash, that is a bad flasher. Your car uses the flasher with the part number of 552, and is available at any auto parts store for nearly nothing.


Kerry said...

Veronica, just wanted to tell you that the turn signal wiring diagram helped me trace a loose wire to one of my rear turn signals. I went around and around and had a hard time pin-pointing the problem until I ran across your "cleaner" wiring diagram that edited out all the other stuff (unlike the one in the Jim Osborn book). THANKS! Electrical is my LEAST favorite work on the car...I've had the 65 Mustang since 1987. I must have jiggled the wire in question loose trying to fix my horn.

What I want to know is what I did wrong when I replaced the turn signal switch to get my horn running the last time? I really think it's just a weak part, but my copper post contacts wore down after two months of driving so that, once again, I didn't have a working horn. Anyone else experience this? It's just a bad part, no? Or is it an adjustment that I failed to do when installing the switch?


Veronica said...

The original Ford wiring diagrams are really pretty baffling unless you already know what's there and where everything is. That was why I started with the original Ford diagrams and erased everything that didn't have anything to do with the system in question.So that they would make sense to people.

That is pretty quick for the contacts to wear down. There isn't really any adjustment on that, other than how tightly you pull the steering wheel down with that big nut on the steering column. It could be that the back side of the steering wheel has gotten a little roughed up and is more abrasive than it was when it was new, but, that would be pretty strange. It sounds like you just got a bad one.

66_Restomod said...

Kerry, don't forget to use a light film of lithium grease or similar on the rings that the spring-loaded contacts ride on. If you use a bare finger, be careful in case of a sharp edge when smearing especially with a new repro wheel or aftermarket hub (for an aftermarket wheel). Hope this helps! (BTW, NOS turn signal switches are still on eBay -- I bought one for $57 a couple weeks ago vs the $80 an OEM costs at a mail order place.)

Hazzea said...

Should the turn signal flashing frequency vary depending on the engine rpm:s?

My turn signals almost don't flash at idle but their flashing frequency increases with higher engine rpm:s (this also applies to the courtesy lights' intensity...)

Veronica said...

What that ususlly indicates is an extremely weak battery. It could be corrosion on the contacts of the flashers, or possibly the battery cable conections, which I would check first, but, if that didn't fix it, I would have the battery checked. The fact that they start working better at higher RPMs tells you that your charging system is working fine, though.

Victor Zarur said...

Hello Veronica: I've had my 1965 Mustang 289 for seven years and everyone once in a while my horn and/or turn signals do not function properly. By accident I
found that by applying pressure to the six wires connector the problem is self fixed, sometimes for years (really)! Anyway, I recently removed my dash cluster to adjust it and the worse came to reality. I could not get my horn and/or turn signal indicator on the dash to work properly. I tried the old tricks and nothing worked. I checked the bulbs and I installed a new flasher, but nothing improved. I must have moved something around when I
removed the dash cluster. This is what I have figured out so far.

I was able to get my horn to work again, this by moving around the bottom left all blue wire (#5 on one of your blog). I had to wiggle it around for the horn to sound again, which is good because if I had to remove my steering wheel
that would be a problem (the previous owner stripped the rod that holds the lug nut for the steering wheel - it cant be removed). Anyway, the wire I moved comes from the steering wheel area. I still cant get the turn signal indicator on the dash cluster to work properly, and the front turn signals to function properly as well. My head lights (both Low and High Beam) work properly, brakes etc. If I turn the signal lever left or right the back lights do function properly, but the front don't. My two front turn signal lights act like emergency flashers with both flashing together, for both the left or right. For clarification, I don't have emergency flashers and the dash cluster is a standard one with just one green light for the turn signal indicator. This occurs even if the back lights are
properly functioning, but the two front signal lights flash together at the same time. After studying your notes and a review of the problem I found that if I pull my light knob out (to the middle only - not all the way) while the turn signal is activated (left or right), my turn signal indicator on the dash cluster turns on - and it stays on with a solid green the flasher clicks stop. If I pull the light knob all the way out during this sequence the flasher clicks start up again, but the turn signal indicator on the dash goes off completely. Sometimes leaving a light faint green of flashes until it goes away. I mention this as its odd, but
verifies that the turn signal indicator (green light) is working on the dash cluster. I hope this message was not to confusing. If need I can send pics of the items.

Veronica said...

After giving this a whole bunch of consideration, I don't see any one obvious problem that will be an easy fix for this. You definitely need a new turn signal switch, which will require the removal of the steering wheel.The fact that things changed when you started poking around behind the dash can only mean that you have issues back there also, and could end up needing to be looked at by someone that knows exactly what they are looking at, how everything is supposed to be, etc... but, you definitely need a new turn signal switch.

Victor Zarur said...

Veronica, awesome information on this web site and I thank you for the research and assistance. The prior day I had been reading all the information you have posed on electronics, I wish I had found your site years earlier. Anyway, I read your info. about the bulbs having two filaments, and being that my steering wheel nut is stuck (I will need to be cut off and hopefully a tread can fix the steering shaft), I got to checking the bulbs on the front turn signals. As I attempted to take the lens cover off to the right front turn light I got some sparks on the lower screw. I found this unusual so I disconnected the battery. I then replaced the bulbs on the front turn signals, cleaned out the housings and rewired the connections (some looked bad). Afterwards, I got my turn signals working again and I was able to reset the blue wire on the # 5connector (under the dash) to get my horn working again. I agree with you, signs are there that is something else is going on, but the unknown with the steering wheel nut is pushing me to find alternatives. The only problem I have now is when I pull my head light switch to the parking lights position with the turn signal on the instrument panel dims and the turn signal clicks slow down along with the indicator light getting freaky. But after a few seconds they get back into rhythm. Could this be tied in to the lamp switch? I'm not sure if this is normal, I only found this by testing all possibilities. But then, who would need the turn signal on with just the parking lights? I cant figure out if that is normal? If not how in the world do I chose the right head lamp switch with the three versions out there? I know that my Mustang was completed Aug. 3rd 1964 and it has both early 65 and regular 65parts with an alternator. Thanks in advance.

Diggler said...

Hello Veronica,

I've had my 65 289 coupe in my family since 1990 and I recently got it back from storage at my Dad's place. I couldn't do the things I wanted to because I was in HS and had no money. Now I have money to mess with the car and have been on a 6 week project. I replaced the gas tank, re-did the trunk, new tail light housing, chrome, etc. New backup lamp kit (backup lights never worked) learned all of the wiring via research. Moved my way in to the cab and rebuilt the rusty fuse box with new connectors, rebuilt the heater box (actually works now thanks to the fuse block rebuild). In the engine I installed new wiring harnesses to replace the originals. I replaced both of the main wiring harnesses with the Mr. Mustang (to original specs) that are in the engine. New starter, new Autolite voltage regulator, new parking lamp kit, etc.

So to my dismay when I fired it up, it worked fine, but the ALT lamp stayed constant and I had just had the alternator and battery both tested and they were both performing as they should. I should also mention that I replaced the original alternator wiring harness too to match the original and it plugs in to the headlight wiring harness as it should and to the positive side of the starter solenoid.

I have no idea why the ALT lamp is staying on. It starts fine, runs fine, doesn't die, doesn't battery drain when sitting overnight. It's just really there to annoy me at this point. So, as a temporary relief from insanity, I removed the ALT lamp bulb. But I am aware that I need to find and fix the issue.

Now... With the car in the on position and the lights off, both turn signals work. Both headlights currently work in low and high beam. The problem is that when I have the lights on, the left turn signal works and the right one does not. The turn signal light on the dash lights up green and stays green. They all have brand new bulbs because I just installed all new kits for the lights. I just don't know where to troubleshoot this issue. And my last thought is that since these cars are so "weird" with electrical stuff, could the turn signal root problem also be the culprit of the ALT lamp issue.

Thank you!

herb p said...

I Have been restoring a 1964 1/2 mustang all new wiring harness and lights. i have everything except the high beam indicator light. the instrument panel is out.can anyone help me out why i dont have the high beam indicator light .ihave even switched bulbs and they all work.except that one. thanks.