The Stovebolt Site Forums The Shop Area The Electrical Bay electrical novice in need of help

well, my 69 only has a few issues left to fix before it becomes my daily driver, one of which is the tail lights/turn signals. OK, first of all, my turn signals all work in the front and in the dash, but not in the back. they come on but blink very dimly. then i pull the head light switch one click and BOTH blink very brightly (and it doesn't matter which way i turn the switch, they both blink if the headlight switch is pulled one click) also, the brake lights come on, but are also very dim. I replaced the ground from the bed frame to the chassis (and cleaned the connections thoroughly on frame, bed,and wire)and also made sure the tallight housing had a clean surface, so what am i missing?






i hope i am clear, like i said, i am a novice at electrical stuff and don't really know what i am doing, so please bear with me and please be patient with my really simple questions



Indy

never-mind my above post, i cleaned all grounds again and now the turn signals work fine, but my tail lights don't come on with the head lights, aren't they supposed to? and my brake lights come on, but are really dim.

Yes they are supposed to. Better revisit the ground again. Grounds can be very weird. Good one minute, bad after vibration during driving, etc. To test the ground theory (after you are SURE the bulb is good) Find an absolute, or create an absolute, clean metal spot and attach a test wire to it and to the socket (not the socket contacts)and see if they light. The best, fool proof, place for testing is the battery ground post, but that is a long wire. Once you confirm it's a ground problem you can fix. If it's not, then set up a separate hot line to test. There are so many features in the "ground circuit" that it's better to use a separate wire to test. You can use continuity or test light testing but if not good with electrics, do the separate wire thing. That's my opinion. Your ground path is bulb to socket case, socket case to light housing, housing to body or frame, then to battery post. Depending how PO's have wired it, the path could have even more steps. Lots of places to be corroded, broken, rusty, loose... If you not sure at all about electrical, you need someone else who is or read up on it. It's hard to advise on this stuff on a forum if you have no experience. But if you are willing, so are we, just be careful that you know how the hot (positive) and the ground works to light a light and how the light has a socket, socket contacts and bulb has one or two filaments. Know how switches work to make various circuits hot.

I think your problems that the tail light wire is going to the turn signals. You have three wires coming off the firewall and routed back to another connector by the spare tire. The wired harness for the rear lights mate to that connector. IIRC the black wire is the tail lights and goes to both sides. The other two wires split one to each side. These wires are are both brake and turn signals. Forgot you have a fourth wire, backup lights. Also check your sockets to make they haven't been molested.

Larry

thanks guys, i tested the grounds again and i still needed to install more grounds, but got most everything working. the brake lights still are acting up but i think i can get them fixed easily, i think the fuse went bad..... too dark and cold to find out for the next few days





Indy

ok, i give up...... gotta ask more questions .

my turn signals work, my park lights work, but my brake lights don't. it isn't a ground, i ran a 20 foot piece of wire from the battery to the housing and they still don't light up. there is 12v of power to the brake switch and the switch is good, but there is no power at the fuse, which is also good (brand new). what am i still missing?




Indy

For one thing, the fuse should be before the switch, not after. If you are getting 12V to the switch without it going through the fuse, something is farmer rigged.

well i finally got 12v at the fuse, it wasn't cleaned very well so my multimeter wasn't getting a reading, i also got the stop lights to work (for now), the turn signal switch is going out on me, so a new one is in order. i followed the directions on this forum

http://67-72chevytrucks.com/vboard/showthread.php?t=366742



Indy

Turn signal going out, there are two parts to the turn signal. If the problem is that the turn signal is not canceling after turn, all you need to replace is the canceling cam. Your doing good we like questions.

Larry

the turn signal cancels alright, but it wasn't very clean, i cleaned it out and it works ok for now.




thanks for everyone's help,

Indy

Hi, Materman, If the rear turn signal/ brake light are dual filament (1157) bulbs install new ones, Also if the front turn signals are 1157 bulbs ( for running lights and turn signals ) replace them also. What can happen is that one filament can break and contact the other filament and power up that circuit to,( brakes to turn signals or turn signal to brakes making the lights dim )

that's just the thing, i did replace all the bulbs with brand new ones

Need an update after no work, works, sometimes, etc. Now what works and what does not work? When you say you "clean" something, what? why? how?...don't forget we gotta ask questions too. Lets take one thing at a time if possible. So how do you know something is going out if you don't test it. Regarding brake lights still not working, you say you ran a test ground wire to them, you DID NOT say they have hot to them, you just said no 12V at switch then yes 12V. What I do is get a tested bulb in my hand and put known power from brake switch to each contact, of the two filament brake bulb, and touch the bulb case to a clean ground while someone or a 2X4 holds the brake on. If it lights I know I can work from there. Then if I place it in the socket using the same hot I get more info. You can do all the checking with a meter or light if you have that.

sorry if my last post came off a little rude, i didn't mean it that way


O.K. first off, everything works as it should in the front. my turn signals and park lights work in the back but only the driver side brake light comes on unless i gently wiggle the turn signal lever around, then the other one comes on again, for a while untill i turn the switch to turn.

what i cleaned was the whole turn signal switch setup in the column, it seemed to help some but i also noticed that the plastic turn signal switch was beginning to crack and deteriorate. i also rewired the back of the truck, which solved some of my previous issues.


please let me know if i didn't cover something.


Indy

You did not come off rude, I just cut to the chase sometimes because I'm anxious to get it fixed. It's either a loose wire, bad contact or faulty plastic actuation part in turn signal, you have to try to look at it while operating, can you take off the steering wheel easily and watch the switch? ALSO make darn sure your flasher relay in the fuse box is good! You can act as the turn signal switch yourself by shorting the proper wires together and see if it blinks each time you try.... and listen for the flasher to cycle. If the switch parts are cracking that means they are flexing and not actuating/operating the electrical switch part of the turn sig assy. Replace it if you see that non actuating while observing it's operation with wheel off. $47.99 O'reilly's PN S3237 or just the cancel yoke PN 49300 or a cancelling cam. Let me know what you see. You are almost there, good job.

well, the switch isn't actuating (and my flasher is new), the little copper connections in the switch are really worn down, so i will probably just get the new turn signal switch. the only issue is my steering wheel doesn't have tilt, this switch is what mine looks like,


http://www.classicparts.com/1967-72-Turnsignal-Switch-Without-Tilt/productinfo/53-509/#


I couldn't find a switch at O'reilly's that looks like it, but is there one that I didn't find?



Indy

That's all I found, did you type in S3237 on O'Reilly's site? It looks the same and is a bit more complete and wired up. More money but no shipping. Easy, easy , easy to take back. The one at our sponser's site is good if you say it has the parts you need.

I believe that Shee-Mar inc makes most of these switches. Does this look like your switch;

http://www.shee-mar.com/PDF/SM208.jpg

I think you can order direct from them or use that part no at your favorite parts source.

Larry

I just posted access to a really nice wiring diagram for your truck.

http://s1109.photobucket.com/user/R...ing1_zpscef3e038.jpg.html?sort=3&o=0

thanks!!!!! that diagram will be a lot of help in the future. as an update, I finally got over to O'reilly's and got the switch, put it in and no more problems thank you all for your advice and help, I will definitely be asking more questions in this part of Stovebolt.




Indy

Thanks for the update. We do like to know how you did. Some of us get to learn with you that way.