Chevy Nova Forum banner

Turn Signal help on a 70 Nova

10K views 25 replies 4 participants last post by  Custom Jim  
#1 · (Edited)
Hey guys,

Once again if you have been following my progress I am learning as I go. I have been successful with your help, tricks, and tips.

Currently my front parking lights are hooked to an alarm system. They flash twice when you unlock the car with the remote. Yeah, wireless automotive door locks, pretty cool. The guy I bought it from did it, but now the front turn signal lights don't work. The parking lights do come on and work correctly, but just no front turn signals. The rear turn signals work great. How in the world do I hook these back up and what do I look for? I don't even know where the turn signals wires are located or where they should be hooked up. Help me guys.

Its okay if you go step by step as if you are talking to a 5 year old, because that is probably where my experience level is right now. Please post pics of what I should be looking for. Thank you. Would love to get this done asap so I look forward to your fast and very thorough replies. Thanks guys.

facebook Nova pic by ssnovass396, on Flickr
20170725_183818 by ssnovass396, on Flickr
 
#2 ·
I would first get in contact with the person that put on the system to see what they say.
I would also get info from that person where they made connections into the original wiring harness on the car this way if issues arise later you know more of how and where things are.
I've been installing automotive electronics since the late 70's and I have my way of doing things and places to connect into the vehicle and someone else will do it a different way and also connect into wiring differently.

Jim
 
#6 ·
Okay, thank you for the tips and for your concern, but can you give me some info and advice on the front turn signals? Where do the wires run out of and maybe I can trace them and then where are they suppose to be hooked to? I have a feeling he unhooked the turn signals and hooked into the alarm. What should I be looking for in regards to the turn signals?
 
#7 ·
Here is a diagram of the turn signal circuit outputs eminating from the turn signal switch:

Image


Basically when you push the turn signal stalk down and it locks to have the left side turn signal lights come on to indicate a left turn, power then comes out of the directional signal switch connector in the above diagram on the light blue wire and in the loom, this wire gets split to where one leg of the split goes to the indash left turn signal light and the other leg goes through the firewall bulkhead connector and then ends up at the left front combination turn signal/parking light bulb.

When you push the turn signal stalk up and it locks to have the right side turn signal lights to come on to indicate a right turn, power then comes out of the directional signal switch connector in the above diagram on the dark blue wire and in the loom, this wire gets split to where one leg of the split goes to the indash right turn signal light and the other leg goes through the firewall bulkhead connector and then ends up at the right front combination turn signal/parking light bulb.

Now with you saying the front turn signals do not work, I have to ask, do the indash turn signal indicator lights work ?. If they do not, I would be testing for power at the column connector as the one half of the turn signal switch for just the front turn signals may have an issue. IF the indash lights do work, then I would be looking at the firewall bulkhead connector.

On electrical plugs with multiple connections,if they are not fully seated you can have issues and if at one point they were unplugged and plugged back in, I have seen connections pushed apart to where not all of the connections in the lug are made.

While you can visually look at electrical systems you may need to belly up to the plate and buy some test equipment such as a test light and/or multimeter and then learn how to use those tools. These tools just like a set of wrenches are needed to check for how tight a nut or bolt is. You can look or twist bolts by hand all day long but this way of checking them gives you no real indication as to how tight or loose they actually are. While a test light is a basic test tool and a multimeter is a more elaborate tool, each one has it's limitations just like a ratchet wrench vs torque wrench.

Jim
 
#8 ·
There is a flasher unit located under the dash in the area to the right of the radio that you could try swapping out. As Jim said for electrical you want to have the right tool for the job to do it properly. A good multi meter will work wonders, but after getting enough experience in wiring to be able to handle things, I really would like a Power Probe IV unit. Something that can send power to a relay and continuity test circuits all in one unit is attractive.

So.... start simple... find that flasher under the dash and replace it... its not expensive at all.
 
#9 ·
Not sure if it needs to be replaced, because the signals work great in the rear and dash, but i think the other guy unhooked the front signals into the alarm. They do flash with the alarm system.

So what am I looking for if I start from the actual front parking light?

I will look for the box to the right of the stereo in the meantime.
 
#10 ·
Guys, sorry its been so long since I have been updating you or following up with this. I did some major other projects for the car installing a full new front grill kit and full new rear suspension.

Back to the front turn signals. I took some pictures. Here is what I go so far. Can you make anything out of this? Let me remind you, the guy before me, installed a alarm system and hooked the front turn signal lights up to the alarm so they flash with the alarm and they do not flash with my turn signals. I want it back to stock.

I am hoping you can look at these pics and see exactly what the problem is and literally tell me to unhook this wire and butt connect those. I am hoping it will be that easy. Please help and if you can explain very thoroughly since I am still new to wiring. Thanks.

These pictures are just behind the front headlights on the driver side under the hood.

20170828_181046 by ssnovass396, on Flickr
20170828_181026 by ssnovass396, on Flickr
20170828_181005 by ssnovass396, on Flickr
20170828_180954 by ssnovass396, on Flickr

Front turn signal

20170828_180932 by ssnovass396, on Flickr

and then a red wire going nowhere coming out of the light. One red wire goes up through to the area in the pics above and another is just tapped off.

20170828_180944 by ssnovass396, on Flickr

Please help. I have no clue what this means. Keep in mind, the guy shaved the side amber marker lights off, so some of those wires I know below to that and even the bulb socket is still here as well. I might put that light back on some day, but lets focus first on my front turn signals.
 
#11 ·
It's hard to see a lot with the pictures but here's what I would possibly do is to open up the harness some by the radiator support and find in the loom the dark blue, the light blue, and the brown wires that go back and into the firewall bulkhead connector.

I would then test them and see if they have power coming out of them at the proper times (right turn signal activated/Dark Blue, left turn signal activated/Light Blue, and the parking lights activated/Brown).

I would then bolt up the bumper parking/turn signal light housings as these MUST be grounded or else a backfeed issue will exist and further hair removal will happen.

You may have to do some testing with connecting a wire or two on the two wires from each bumper mounted parking light/turn signal light combination bulb so that when just the parking lights are on, the lower wattage/lower brightness portion of the bulb lights up and then when the turn signal for that side is turned on, the brightness increases.

On the side marker lights, these have just the brown wire going to them and then a black wire which goes to a good ground.

Here is a diagram of just the front turn signal wiring and parking light wiring from the firewall bulkhead and out:

Image


Jim
 
#12 ·
Thanks Jim, okay two things. Its hard to visually see what its suppose to look like from the diagram. Do you have a real world example of what that would look like?
Second, I can head to the store and get a test light or something, what would I need exactly. I don't need an expensive one and I am not going to do much wiring if at all after this, so a cheap and easy one would be best.

Maybe you can tell me where I can hook it? From the back of the parking lights there are two red wires. One goes up into the harness and the other is tapped off and zip tied to the frame just hanging. That is obviously my turn signal wire. So what can I hook that into? Please see pictures again and you can see semi what's going where.
 
#14 ·
I got the turn signal lights fixed. Quick question though.

On our 68-72 Nova's when at night and we have out headlights and parking lights on steady, when we turn on the turn signal what is suppose to happen? The the steady light turns off and now only become a blinker, or does the steady light stay on and just become brighter when flashing?

Please let me know ASAP because my mechanic totally messed things up and I have to go talk to him tomorrow. Thanks.
 
#16 ·
At night and we have out headlights and parking lights on steady, when we turn on the turn signal what is suppose to happen ? Thanks.
With the headlights on and the parking lights illuminated the signal will flash brighter while the parking light in the bumper remains on.

These cars use an 1157 or 1157A (A=Amber bulb 1970). The 1157 is a dual filament bulb, so it will allow for a running light and a bright light for the signal or brake.
How Taz3 described things are how they are to work. With you asking if the steady light turns off, this is NOT how it is to happen.

While I can understand the design of the dual filament 1157 type of bulb, if things are not right with the socket and/or the wiring, strange things can happen.

On an 1157 bulb, they have a common ground for each filament. With this common ground properly grounded if you apply 12V to one of the two remaining terminals the one filament will come on and make light. If you then remove 12V from that terminal and then apply 12V power to the remaining terminal then a different filament will come on and make light AND this brightness may be brighter or dimmer than how it was when power was applied to that other terminal. An 1157 bulb has two filaments in it and one is a higher wattage than the other.

The issue that can come up with the design of the 1157 bulb is if the bulb is not grounded and the other two terminals of the bulb are attached to existing wires on the car.

Let's take an 1157 bulb and if it is not grounded and we apply power to one terminal, power then wants to go through the filament on that portion of the bulb and wants to try and go to ground but if it cannot find a ground, it will look for an electrical path through the other filament. When this type of bulb is un-grounded and we apply power to the low wattage portion of the bulb which would be connected to the cars parking light output of the headlight switch, then power then since it cannot find a ground now backfeeds or sends power back into the higher wattage filament portion which is for the turn signal and then the power continues back the wrong way on that circuit and if it is a front light, then the indash turn signal indicator will glow.

I hope I'm not making this too long explaining things but he design of the 1157 bulb is decent BUT the socket and wiring it attaches to also has to be right for things to work as designed.

Ideally if I were to design a system using the 1157 bulb, I would add diodes to the wiring on the lights socket to prevent back feeding BUT for GM to do that originally would have cost more money and now with this type of bulb on older cars, the sockets and/or wiring can be poor and it can give one all kinds of headaches trying to figuring things out.

When the parking lights are on, only one filament (the lower wattage portion of the bulb) will be on and then when the turn signal is turned on and sent to that light, then the lower wattage portion still stays on but now the second filament comes on and the light becomes brighter.

Jim
 
#15 ·
With the headlights on and the parking lights illuminated the signal will flash brighter while the parking light in the bumper remains on.

These cars use an 1157 or 1157A (A=Amber bulb 1970). The 1157 is a dual filiment bulb, so it will allow for a running light and a bright light for the signal or brake.
 
#18 ·
Jeesh, you want it all don't you !!!!!!:D

I myself have NO idea which is which unless I were to test one but if I only had to do a visual look at one and take a guess, I would think one would have more filament than the other and it would be the brighter one and the brighter one for the turn signal portion ?.

Hey, I have a 50/50 chance of being right.

Jim