Turn Signal Gremlins

Tech tips and how to's

Moderators: notoptoy, S Allen, Solex68

User avatar
jrusso07
Roadsteraholic
Posts: 1694
Joined: Sat Aug 02, 2008 9:02 am
Location: Penn Yan, NY
Model: 2000
Year: High Windshield-68-70

Turn Signal Gremlins

Post by jrusso07 »

1970 SRL, right front turn signal no flash. Rears flash, dash flash, voltage to lamp flashes, new bulb, cleaned grounds, bot filaments light with 12v jump from battery. All bulbs flash with hazard switch on.

Conditions

Running lights - all bulbs light
Left turn, all left lights flash - relay clicks, dash light lights
Right turn, all right lights flash except passenger front. Voltage at harness input flashes (pulses), flasher relay clicks
Hazard with turn signals off - all lights flash
Hazard with turn signals on - all lights flash, turn signal flasher stops and hazard flasher starts.

So, bulb is good, ground is good, connection is good. Next step is pull center console side cover and check connections to flasher but the odd thing is that all the conditions seem correct.

Help, Curtis? help
Joe

1969 SRL311 - Solex
1970 SPL311 - U20 mod
1970 SRL311
User avatar
Habitat.pat
Roadsteraholic
Posts: 602
Joined: Thu Jul 07, 2016 8:29 pm
Location: Central Texas
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Turn Signal Gremlins

Post by Habitat.pat »

Try turning the 4 way flasher switch off & on a few times. Could be dirty/oxidized contacts in the switch.

Peace,
Pat
67.5 SPL311 Stroker Restomod
Pat Horne, Near Austin, TX
We support Habitat for Humanity
A hand UP, not a hand OUT
User avatar
Bwk2000
Roadsteraholic
Posts: 912
Joined: Mon Aug 23, 2021 3:09 pm
Location: Halifax, Nova Scotia
Model: 1500/1600
Year: High Windshield-68-70

Re: Turn Signal Gremlins

Post by Bwk2000 »

Well, I’m not Curtis but I’ll give it a shot anyway:
Try supplying 12v direct from battery to right turn signal wire coming directly off the signal lights flasher.

If the filament in the bulb DOESN’T light up, the problem is likely a loose/broken splice in that wire. If it DOES light up, the problem is likely the contacts in the signal light flasher itself.
Last edited by Bwk2000 on Thu May 26, 2022 6:24 pm, edited 1 time in total.
Kai
Halifax, N.S.
’69 SPL311 Sports 1600

Classic Cars - Because clean fingernails, free weekends, intact knuckles and financial stability are totally overrated.
User avatar
bikermike
Site Supporter
Posts: 1761
Joined: Wed Jul 06, 2011 4:06 pm
Location: Denver Area, CO
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Turn Signal Gremlins

Post by bikermike »

Have you tried swapping the hazard flasher can with the turn signal one?
-Mike
1967.5 SPL311
1972 240z / L28
2003 BMW 525i Touring
2014 Jeep KL
User avatar
redroadster
Roadsteraholic
Posts: 2408
Joined: Tue Mar 12, 2013 10:58 am
Location: KCMO
Model: 1500/1600
Year: High Windshield-68-70

Re: Turn Signal Gremlins

Post by redroadster »

It lites on rf but no flash ? And the other side works fine

It needs a draw enough amps to blow the circuit breaker then reset then blow ....add a redundant ground , the metal that contacts the bulb often gets corroded and block amps
Sometimes sanding litely on the bulb contacts or different one , with a test lite check brightness at battery
Then at bulb socket contacts , or better voltage drop / amp test
Also had probs with the newer 1157 replacement bulb
1130 ? not working
Last edited by redroadster on Sat May 28, 2022 7:56 am, edited 2 times in total.
Datsun dealer tech 76 to 87
Mitsubishi tech 9 yrs
Volvo, Kia, Toyota too
6 month - Rolls Royce
ASE MASTER TECH 96. - 11
70 SPL 86 Z31 T , Sportster
User avatar
jrusso07
Roadsteraholic
Posts: 1694
Joined: Sat Aug 02, 2008 9:02 am
Location: Penn Yan, NY
Model: 2000
Year: High Windshield-68-70

Re: Turn Signal Gremlins

Post by jrusso07 »

So, I can light both bulb filaments by swapping the running light power with the blinker power. I can light both filaments by supply 12v jumped from battery + terminal to the lamp contacts through the lamp harness (bullet connectors at the top of the fender front). Hazards work fine - all bulbs flash with or without running lights on. My conclusions are that grounds are good, bulb is good, harness is good, flasher relay (bimetallic breaker) is good, turn signal switch is good.

I will try swapping the hazard and turn signal flashers but all the other lights work on the turn signal flasher, including the dash indicators. I haven’t exercised the hazard switch to remove oxidation yet but I am betting on that because i can't think of what else would be the problem?
Joe

1969 SRL311 - Solex
1970 SPL311 - U20 mod
1970 SRL311
tangoterje
Roadster Nut
Posts: 27
Joined: Mon Sep 28, 2020 1:16 pm
Location: Oslo
Model: 2000
Year: High Windshield-68-70

Re: Turn Signal Gremlins

Post by tangoterje »

If you get dash light on right turn, then it’s probably not the turn signal switch (phew!). Referring to Curtis’ drawings, there’s probably a breach between pt 5 from turn signal switch and the joint that delivers power to the hazard switch and onto the front right turn signal.
You do not have the required permissions to view the files attached to this post.
User avatar
jrusso07
Roadsteraholic
Posts: 1694
Joined: Sat Aug 02, 2008 9:02 am
Location: Penn Yan, NY
Model: 2000
Year: High Windshield-68-70

Re: Turn Signal Gremlins

Post by jrusso07 »

Thanks - agree there is a break in the circuit somewhere to the Hazard switch. I exercised the hazard switch to try and revive the contacts but no Joy. Switching flasher relays did not correct. Will get the ohm meter out and trace the circuits back to the switches
Joe

1969 SRL311 - Solex
1970 SPL311 - U20 mod
1970 SRL311
tangoterje
Roadster Nut
Posts: 27
Joined: Mon Sep 28, 2020 1:16 pm
Location: Oslo
Model: 2000
Year: High Windshield-68-70

Re: Turn Signal Gremlins

Post by tangoterje »

Have you checked contact points with an ohm meter? Probably a good thing to check anyway, but as you can see on the diagram when hazard is off, the RF light gets 12v straight from the turn signal switch, omitting the hazard. But as you said, dash right indicator also flashes when turning right, and as both dash indicator and RF light gets pow from same source on TS switch, pt 5, then it must be a breach in the joints or wires. TS switch probably also fine :)
User avatar
Curtis
Site Supporter
Posts: 4061
Joined: Fri Jan 01, 2010 2:49 pm
Location: Des Moines, WA
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Turn Signal Gremlins

Post by Curtis »

Here I am. I would suspect the contact in the turn signal switch. Rear turn lights and front turn lights each have their own contact inside the switch. The 69-70 switch is much more complicated inside. If you look at this drawing you'll see how the contacts in the switch route power.

http://kendo-usa.org/datsun/datsun_park ... _69_70.pdf

If you unplug the turn switch you can check by jumping the white wire and green/black wire in the dash side of the plug with power on. If it still doesn't work then the hazard switch could be the problem.

Yes I would turn the hazard switch off and on a few times to start with. The contacts inside get all gummed up. They can be cleaned. I would first try spraying contact cleaner in it although there isn't much place to try and get it inside. They are a fussy little thing to take apart with contact balls and springs inside.
66 stroker, almost done.
67 basket case, paint coming soon.
User avatar
jrusso07
Roadsteraholic
Posts: 1694
Joined: Sat Aug 02, 2008 9:02 am
Location: Penn Yan, NY
Model: 2000
Year: High Windshield-68-70

Re: Turn Signal Gremlins

Post by jrusso07 »

Thanks Curtis and Tangoterje. I will dig into the turn signal switch. The curious thing is there is flasher voltage at the connector (green with black strip) to the lamp harness. It pulses with the flashes. But I have only tested it unloaded so it must be a high contact resistance somewhere. I will test it loaded with the lamp filament and see what happens in addition to checking and cleaning the turn and hazard switches)
Joe

1969 SRL311 - Solex
1970 SPL311 - U20 mod
1970 SRL311
User avatar
Curtis
Site Supporter
Posts: 4061
Joined: Fri Jan 01, 2010 2:49 pm
Location: Des Moines, WA
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Turn Signal Gremlins

Post by Curtis »

The bulb sockets get corroded inside and can cause connectivity problems. The 69-70 use the small plugs and the pins can get bent inside.
66 stroker, almost done.
67 basket case, paint coming soon.
jayedeluxe
Roadster Nut
Posts: 56
Joined: Sun Apr 12, 2020 3:50 pm
Location: san diego
Model: 2000
Year: High Windshield-68-70

Re: Turn Signal Gremlins

Post by jayedeluxe »

I also have a 1970 SRL, I'm wondering if any of you guys have removed the whole center console, and heater core/radio/choke/hazard switch assembly box ? I did, to just give it a clean look, but now I have no turn signals. And yes, I knew that would happen. I've seen it a few times, and the ones who did it are fine with no blinkers. I'm thinking I would like to have blinkers, hazards not so important. From what I read though, it seems the blinkers use the hazard relay and switch to work ? This sounds like some creative wiring might need to be done. Beyond my scope of expertise. Does anybody no of anyone in San Diego county who could do this ? Thanks
Captainkaos
Roadster Newby
Posts: 18
Joined: Wed Oct 26, 2016 9:46 pm
Location: San Diego, CA

Re: Turn Signal Gremlins

Post by Captainkaos »

Hi Joe, I had a similar issue on my ‘68. Flashers, parking lights and driver’s side turn sIgnal worked, passenger side no turn signal. Turned out to be the turn signal switch on the steering column. The small piece of metal that pivots from side to side had worn down enough that it made good contact on one side and not the other. Took it apart and cleaned it and then got passenger side signal but not driver! Third time was not the charm as we ended up cracking the small piece of fiber board that holds the assembly together. Bought a new switch assembly, and voilà everything works. Hopefully just cleaning the assembly might work.
Dick
'68 2000
Pacific Beach
User avatar
Curtis
Site Supporter
Posts: 4061
Joined: Fri Jan 01, 2010 2:49 pm
Location: Des Moines, WA
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Turn Signal Gremlins

Post by Curtis »

A 69-70 turn signal switch can be made to run all the turn signals without the hazard switch. But you run in to a problem with the brake lights.

The hazard switch is a pain because so much is tied through it including the brake lights. To eliminate it you would have the front turn lights come on too when you brake. If you want hazards it would need a DPDT switch also.

I just sat here and diagramed it out on my drawing.
66 stroker, almost done.
67 basket case, paint coming soon.
Post Reply