Turn Signal Help

[rutkak]

Ladies and gentlemen,

Can you please help me out? My turn signals blink REALLY slowly when the lights are off and turn bright and don't blink when the lights are on. With the lights off, the turn signal lights kind of look like they blink very very very dimly twice and then on the 3rd blink it's normal (if that makes sense). The hazards do the same thing - blink normal with lights off and stay bright with lights on. Additionally, when the lights are off, the right turn signal stops blinking when the heater is on the highest setting. It blinks when the heater isn't on the highest setting. Wierd. I'm thinking grounding.

I've checked the grounding as best as possible and everything looks okay. I've swapped out the turn signal flasher with one from O'Reilly auto and it didn't blink at all (same model). I cleaned up the turn signal flasher ground (or the one right by it about the glove box).

Background: I just put my gauge cluster back in. I got a gauge tach conversion by RCCI (Bob McMullen) and it works great! I wired the 3 wire tach exactly as my previous aftermarket tach so I'm guessing that isn't the issue but you never know. All the lights work in the cluster and my seperate 3x gauges for eng temp, oil press and voltage I mounted beneath the dash. .

I have a 72 Coupe, 289 2bbl with 1 wire alt, + full length mach console, electric fan. Everything else should be typical.

-KR

 

[Don C]

Sounds like you're not getting full power to the fuse block. I would start at the connection at the solenoid and clean all connections between there and the fuse block. Also make sure the ground from the battery to the body and engine are good. The old glass fuses can become corroded inside, also, so I would replace all of them, too. And, then work your way out to each light, cleaning all of the connections.

 

[caspianwendell]

Sounds like a ground problem or lack of actually. is it just the rear section? check all ground connections, take them apart and clean them real good is where I would start

 

[rutkak]

Gents,

Thank you for the reply. I checked the solenoid and put more dielectric grease on her. I've been through the grounding gremlins before so they were pretty clean. I always get metal on metal with dielectric grease in between.

I replaced some fuses and put on dielectric grease with no change. I disconnected the RCCI tach (only thing recent) all together with no change. I checked the grounds for the body, block, block to body, tach (in cluster), my mini cluster and the turn signal relay.

I'm thinking grounding as well. The appropriate exterior lights blink (left and right, front and back) when the lights are off but when the lights are on they are just lit up solid on which ever side the indicator is selected.

I'll recheck the front and tail light grounds but I cleaned them up a few months ago.

Any other suggestions?

KR

 

[caspianwendell]

Had an impala in the shop with a similar problem and it ended up being turn signal switch. somehow your bypassing flasher when lights are turned on. midlife should be able to help you out

 

[rutkak]

I replaced the Turn Signal Relay with a high end, heavy duty model ($12 vs $4) and the turn signals blink at an expected rate now. I returned the cheapo relay that didn't work even though it was the exact same model as what I had in there.

My turn signals still won't work when the lights are on, but it's almost as if they pulsate but the headlights being on overpowers them.

 

[Jim and Jutta]

I was having issues when I turned my headlights on like the head lights flashing on and off like emergency flashers, put a new headlight switch on and it that took care of it. Doesn't sound like your problem but a worn out headlight switch will cause the lights to do weird things, just something to consider.

Jim

 

[72HCODE]

try this.

go to the front of the car, reach up behind the front valance and disconnect the front turn signals. or you can unscrew the amber lense, and pop out the light bulbs.

go back in the car with the front signals disabled and cycle the blinkers and see if they go back to normal on the dash and view the taillights.

if the blinkers now work correctly then you have the usual issue of the front turn signal holder buckets corroding and shorting out ground.

good news they make them reproduction now. slightly bad news the repops have the mounting studs slightly in the wrong spot, so you will have to drill out new holes in the valance or elongate your original holes.

reconnect the new signal houses to the harness install the bulbs and put on a new foam gasket and your turn signal lenses and you will be good to go.

if you still have the problem after disconnecting the front lights start to look at the tail light sockets they can rust and short out as well. you can remove a light bulb one at a time until the problem reveals itself.

the tailights are a little more protected then the front signals so they are slightly less a problem. the front ones 95% are the cause of turn signal issues and 4way hazard problems.

with the headlights blinking on and off, you have to be a little careful in the type of bulb you use. the headlight switch is rated for 35W/55W bulbs. a lot of bulbs are now 55W/65W or 65W/85W because people want the headlights brighter and brighter. the Blinking of the headlights indicates you are overloading the switch. there is a special fuse inside the headlights switch a bimetal reed that shuts down the headlights when it overheats.

now an older original switch is going to shutdown faster then a new switch because the older switch has more metal fatigue in the bimetal switch. so many guys do just change the switch and the problem goes away. However you are now overheating the connectors behind the dashboard. at some point they may melt the plastic and either stop working, cause a bad contact, or start a fire, it is possible since many people put halogen headlights on the cars, some times that reed switch can be stuck or a spot weld occurred and the switch can not turn off.

I had the issue on my car because i changed to halogen lights. i installed a new switch and i noticed now hot my headlights switch harness was. I did some researched and discovered the correctly way to use halogen on older cars was to use a headlight switch relay. the headlights switch in the car turns a low amp relay on or off and the relay takes power from the battery directly to the headlights, this bypasses the load on the headlights switch.

I decided i didn't want to go that route and i bought reproduction ford OEM spec headlights that are 35W/55W bulbs and never had a problem with the headlights blinking again. course the headlights are much dimmer then a modern car.

 

[rutkak]

Gentlemen,

I took 72HCode's advise and checked the front, then back lights. I disconnected the front pigtails and pulled the bulbs in the back. No change. I checked pretty much the entire car in some manner with multiple combinations of bulbs or not. At least it gave me a chance to put another application of dielectric grease on all the sockets. I found one ground wire that was cracked but it was on the front right parking light pigtail so I unplugged it so it wasn't in system. All the other wires looked fine. I have a lot of LED bulbs but I pulled them from system when troubleshooting.

Again, my turn signal work fine unless I turned the parking or normal lights on they they stay lit up. It almost looks like they pulse on the gauge cluster a little but they definitely don't blink.

Any other thoughts? I'm kind of at a loss unless the headlight switch is shot.

 

[midlife]

Turn signal to parking lamps suggest corrosion on a side or parking light bulb socket. The side marker lamps have the push-in bulbs, and these are notorious for corrosion issues. I'd check there next.

 

[72HCODE]

Ok you didn't mention the LEDs.

Do you have LEDs on the turn signals?

If you do that is the problem. LEDs are low current draw. The flasher unit requires a level of current to set off the bimetal switch inside. When you use LEDs you must change the flasher from electromechanical to digital. The digitial flasher usually needs its own 12v input so you may need to run 2 12 volt wires from the ignition on circuit to the flasher units, one for blinker the other for hazard lights.

It's a pain and I went back to regular bulbs on my car.

 

[rutkak]

Thank you 72HCode. I swapped out the LEDs and the blinkers work now. +1

I feel like an idiot. I should have known better! I put those in several weeks ago, but either didn't drive at night since then and I just installed my Rocketman Idiot Light Tachometer so I figured I jacked something up, busted a wire or was shorting something out.

First 3 beers are on me if you are ever in Fayetteville, NC or Quantico, VA (moving there in 2 months).

My sincerest thanks to all that replied, especially 72HCode.

-KR

 

[caspianwendell]

Now the story makes since...lol

 

[whitesoc]

I've been having the problem of just my left turn indicator light staying on in the car( no headlights on) I do have LED's in the dash could that be the problem there also?

 

[72HCODE]

in the dash shouldn't because of the load from the other 4 lights. I had turn signal LEDS in my dash panel that caused a different problem but my blinkers worked as normal.

you may have a ground problem like i talked about before in the thread.

the issue with LEDS in the dash board turn signals is when you drive at night it is like somebody shooting a MAG flashlight in your face blinding you.

the only place i kept the LEDS was in the dash for gauge lighting, even those I'm not happy with but they are improvements over the OEM with the blue light filters.

@rutkak Hey glad i could help. small things can drive you insane on these classics