I'm working on a 69 cutlass and the right turn signal flashes but the left lights up but doesn't blink any help would be much appreciated will a bad flasher cause one side to work and the other not to work?

 

It could, and flashers are cheap and easy to replace. But it could also be a bad turn signal switch or a problem in the wiring. But I would change the flasher first.

Did this problem just crop up suddenly, or did it occur after some work had been done to the car?

 

it's been like this for awhile I just swapped the jetaway transmission for a thm 350 but the turn signal issue was there before

 

Actually, now that I think about it, I really don't think the flasher could be the problem because I don't think the circuitry for each side passes through the flasher separately. I think the flasher is in the circuit before the turn signal switch, so if one side flashes, the flasher is fine, and the problem is elsewhere.

I had a '75 Chevy Nova once that stopped flashing on one side. It did turn out to be the turn signal switch on the steering column.

 

Here's what a turn signal flasher looks like ($6.99 at Autozone). Note that it has only two prongs. It would need more than that if there were two separate circuits running through it. I don't think your problem is the flasher.

 

The same flasher module controls both sides, so if one side is working, the flasher is fine. The problem is either a burned out filament or a bad ground. Keep in mind that the 1157 bulbs have two filaments, one for park/tail lights and one for brake/turn lights, so you can have a bad brake/turn filament even if the park/tail lights work.

 

^^^ What Joe said. I had this happen with my car a few years ago. It was the ground on the front signal light. General note: The system is designed to go solid green in the event you burn out a bulb used for signalling.

 

Mine does this off and on.One day it will go green then it will work for months.Seams like the more I drive the car and use it the better it works.Strange. Im sure its in the signal itself.I have a new one but am affraid to tear in the steering column and change it out.What happens if I make it worse!!!!!!!

 

Probably a corroded light bulb socket.

Next time it does that, walk around the car and look to see if one light is off.

- Eric

 

Thanks for the advice.I does seam that its just the one in the drivers tail light. Could to much of that (dielectric) grease you put in sockets cause a short.If so should I clean them out or replace it.

 

Generally, no. The dialectric grease is there to prevent corrosion. Chances are you just have a bad bulb.

 

OK I just went to my car and tested out my Blinkers both sides worked perfect until I turned on the headlights! When the headlight went on the left or drivers side turn signal stopped working and the green inside indicator lit up,then I turned the headlights back off the signal started working properly.Can someone tell me what to do to fix this? Thanks

 

We already did. It's still a bad ground. Find it, clean it, reassemble.

 

Would the bad ground be under the hood or under the dash?

 

It will be one of the ground wires from the lamp sockets, or a corroded socket or an ill-fitting bulb base that doesn't ground properly or a corroded bulb base.

 

I would think you could quickly pinpoint the problem area by testing each socket with an ohm-meter, and, if you don't have one, getting a volt-ohm meter is a worthwhile investment for anyone working with old cars.

With the bulb removed and the power to the bulb off, touch one lead from the meter to the ground side inside the socket and the other lead to another metal part of the car, such as the bumper. You should read continuity (0 Ohms resistance). If any socket tested doesn't result in this, check that socket's ground. Also, a few Ohms resistance isn't good, and could indicate a poor ground but not a completely open ground. You want zero Ohms.

 

You need a high impedance VOM for this. If you use a low-impedance tester, it's possible that a ground will show good with the tester but still won't conduct enough current to light the bulb. A better test is with a test light, but since you are testing for ground, you need to clip the alligator clip on the light to the battery plus terminal (likely using a jumper wire) and touch the probe to the ground in the socket. The impedance of the test light filament will be a better test.

 

The ground for the lighting harness is on the rad support just in front of the battery. Look there for corrosion. Do the park lights work fine without the signal on?

Also, the front light harness had a 'park and turn' signal lead. Check that connection to see if any of the contacts there have corrosion. Look on page 138 (section 12) of the 1969 Cutlass Assembly Manual.

 

I removed the drivers side parking light and noticed only one filiment was flashing the other would not lite.So I changed the bulb to a new one and It did the same thing.When I put the blinkers on it will flash only half as bright as the other side.Its got to be in the socket? Right?

 

Right. Just like we've been telling you.

Corrosion and/or a bad ground.

Clean the socket up well and check the ground with a test light like Joe said.

- Eric

 

Eric/Joe
ostie13 is not the OP of this thread. Check permalink 10. That's where he jumped into the thread. He says that the socket has dialetric grease in it, so I don't think the problem is corrosion there. I suspect it's the ground more than anything. The dim light condition he states is a real obvious indicator (no pun intended).

ostie13 - Your bulbs are fine. There are supposed to be 2 filaments in an 1157 bulb. One is for light function, the other is for brake/signal. The fact that you get a weak filament compared side to side means you're not getting the proper voltage tp the socket on one side. This doesn't sound like socket trouble - especially since your hazard lights work. This sounds like a bad ground on the light harness at the tail lights. That's where you said the problem was to start.

What kind of car are we talking about here? The OP said he had a 69 Cutlass. What is your car?

 

Now I'm totally confused.

But I will say that even with grease the socket could be corroded. For instance, a previous owner could have put grease on an already-corroded socket, believing that would somehow fix it.

While you're there always at least give them a quick check and a wipe with a wire brush or sandpaper.

- Eric

 

Actually, if the other light is illuminating BOTH filaments when the turn signal is on, THAT'S the side with the bad ground. In that case, the turn signal circuit is grounding through the parking light circuit, which is why both filaments come on.

 

I didn't read his post to say that Joe. He simply states:
His post suggested that he wasn't aware that the 1157 only uses one of the filaments for signalling/brake and one for running lights.

 

You're correct. I ***-U-MEd that if he was surprised that only one filament was lit and the bulb was dimmer, it was because he had looked at the other one and both were lit, but that was just an assumption.

 

OK quick update i replaced the flasher...The front drivers side turn signal has no power. The parking lamp filament works. The hazard light does not work for front left....all the other ones work fine any ideas??? Any one have the wiring schematic for the 69 cutlass?

 

If somebody can email me wiring diagram for 69 cutlass i would greatly appreciate it. My email is crxr61313@gmail.com

 

Go to wildaboutcars.com, sign up (it's free), and you'll find the complete '69 Olds factory service manual there. It contains wiring diagrams.

 

thanks jaunty I'll check that out i think i narrowed it down to bad wire or turn signal switch....

 

As I said, corrosion.

The terminal for the high-watt filament is corroded, or the wire is off of it, or the corresponding terminal in the plug to the harness is corroded.

And a bad ground is still in the range of possibility.

You'll find the wiring schematic on page 12-2 of the 1969 Oldsmobile Chassis Service Manual.

You'll find the 1969 Oldsmobile Chassis Service Manual at WildAboutCars for free, but you should buy an original paper copy as well.

- Eric

 

Checked all grounds are good checked the wire before it goes in the socket still no power. I'm leaning towards it being a bad switch. I'm going to check for power under the dash coming out of the switch tomorrow. Thanks for the info though that diagram was extremely helpful.

 

Check at the signal light switch plug on the steering column, which can be done without a lot of disassembly.
You can also feed current into the proper wire for each light to confirm function.

- Eric

 

I have a 71 Toronado.I will check all grounds to find the problem.I am sorry if I jumped into this thread.I was having a simular problem as CRXR61313.Im fairly new to adding comments to this forum and probably have used bad etiquette because I usually just read the forums. I really enjoy and feel like I have learned so much from you guys. Thank you all for your help.I will let you know what I find.

 

Ok ordered the turn signal switch it will be here wed I'll let ya guys know how I make out thanks to everyone for all your help

 

No harm done, just caused some confusion with some of the help replies. Joe and Eric thought they were dealing with only one person...

Don't feel bad, the forum encourages discussion and the fact that 2 guys are having similar problems may help expedite the solution.