Troubleshooting a turn signal switch in an FJ40? (2 Viewers)

[Reeve Kook]

Hello, I have posted about this problem before, regarding one side of turn signals not functioning properly, but now nothing except the hazards work. I am fairly certain that the turn signal switch on the steering column went out all of a sudden. I have hooked a multimeter onto the switch, even putting the meter in series with the circuit, but nothing, no continuity. However, I am just making sure that I am not being a complete idiot and testing it the wrong way. It is difficult to do a visual inspection without getting the steering wheel off, which requires a puller. Any help appreciated, thanks!

 

[Reeve Kook]

I am also in a little bit of a hurry since my new carburetor will be arriving soon and the only thing keeping this thing from being road legal is the turn signals.

 

[Marn0]

Check all your turn bulbs. there are 2 in the front one large one small. they wont work properly if the small side bulb is broken.
Try putting your hazards on. Does that make them all work?
Take off the plastic surround from around the switch and clean every contact you see.
I think they also go through the hazard switch so maybe pull that apart also and clean all contacts and grease with a little electrical grease.

That should keep you busy for a bit.

 

[Reeve Kook]

Hazards work without a flaw. I have a fender off right now, so I have a trailer light in its place. Still nothing. Before this was all happening, the right side was working fine, then one day I noticed it was a little sporadic, then it quit all together. Sounds a lot like a bad ground. Maybe a faulty ground at the turn signal switch itself? I had put a meter up to it by grounding the meter to an exposed bit of metal on the column. That came up with no continuity, no matter if it were left, right, bright, dim. But my high beams work fine, so this doesn’t make any sense.

 

[Reeve Kook]

Also, I assume when you say 2 “bulbs”, you mean 2 filaments within one bulb, correct?

 

[Marn0]

Also, I assume when you say 2 “bulbs”, you mean 2 filaments within one bulb, correct?

No, two seperate bulbs. One in the main blinker compartment and one in the little side facing blinker bit

 

[Reeve Kook]

No, two seperate bulbs. One in the main blinker compartment and one in the little side facing blinker bit

oh, the side markers, those are not present on the car, PO removed them. But the signals worked without them. I guess it wouldn't hurt to hook some sort of light to the side markers to draw current.

 

[Reeve Kook]

oh, the side markers, those are not present on the car, PO removed them. But the signals worked without them. I guess it wouldn't hurt to hook some sort of light to the side markers to draw current.

I did some testing though, and side markers only come on only when the headlights are on, so it should be fine to ignore them, right?

 

[jjenloe]

I had the same thing about 2 months ago. No turn signal, but the flashers work. I was just about to go down the rabbit hole, but something told me to check the fuse. I checked it and it was blown. Replaced it and all is right in the world.

 

[Marn0]

I did some testing though, and side markers only come on only when the headlights are on, so it should be fine to ignore them, right?

the actual indicators themselves have two bulbs. Not the side markers

 

[thebigredrocker]

@Marn0 I think he has 73 turn indicators, so just a single bulb and apron mounted side markers.

@Reeve Kook On the front turn housings, make sure the mounting nut has metal on metal contact with the bracket underneath the fender. Make sure at least 1 of the 4 bolts that attach fender to frame rail have metal to metal contact (bolt flange to fender brace). You can also add a ground path where the fender attaches to the cowl. Might as well clean up a ground where front side apron mounts to the fender.

Also should clean up a ground spot where rear turn housing bracket attaches to rear cross member.

The flasher relay is current driven so in hazard mode(even with less that perfect grounds) you've got enough current to flash. But in turn mode you need both front and rear grounds to be perfect.

Also would be good to scuff the bullet connectors. It's a pain, but you could also pull the spade connectors where your rear harness plugs into the main harness. You just need to grind a small screw driver down.

If you do all that and no dice, sometimes a dirty hazard switch is the culprit. Turn signal current flows through the hazard switch. Pull it, bend 4 tabs and scuff the internal contacts. Add smear of dielectric grease inside the switch.

 

[pb4ugo]

If you have exhuasted all the external connections, getting to the turn switch is not that difficult. You can get a puller to remove the steering wheel from your local autoparts store thru their loan tool program. The switch is very simple and basic.

 

[Reeve Kook]

I have pulled the steering wheel, and have determined that the turn signal switch is fine. I then realized the fuse block has some decent corrosion on it. I cleaned it and now I have my signals back, but the left side still justs blink once then stays on which I mentioned on a previous thread. The only culprits left are the flasher relay and the hazard switch. I just took the relay out and tested it with a light hooked up to its output, it still does the click twice and stays on. I am pretty confident it is the relay.

 

[Reeve Kook]

I also tore apart the dash, cannot figure out how to get back there and remove the hazard switch. I can see the back of it, and I don't see any corrosion of any sort on the back of the switch. All connections are shiny and are being protected by a clear boot.

 

[Reeve Kook]

I just took the relay apart and fiddled with it. I put a trailer light on the front because the fender is off along with the factory light. apparently there wasn't enough current to make the left side function. I believe it is because the left front signal has a pretty crusty connection to the fender. So now everything seems to be working. Now just gotta get a new light because I beat the ever-living hell out of the old one since it was so rust/paint welded to the fender. Thanks a ton, I can finally get it street legal.

 

[stoshzack]

Yep - I was going to say that it sounds like a classic ground issue. But it sounds like you have it figured out.

 

[Clubtroy]

Hi Guys,
I have been down this rabbit hole for 3 weeks now. No front turn signals on my 75 FJ40. Hazards flash fine everywhere but no turn signals on the fronts. The only wiring I don't have on is the license plate lights as that is still in process. My Q is this: Is the turn signal relay working if the hazards are flashing on all 4 lights (front & back signals)?
Q 2: Can I rule out a bad turn signal relay and focus on the actual turn signal switch on the steering column? Any help is much appreciated!

 

[Cromagnon]

There is only one flasher, if your hazards work then the flasher is good.

If the rear turn signals work and the fronts do not, then the problem is the front lights, sockets, or wiring. Why would you work on the turn signal switch if the rear turn signals work? As stated in my first sentence it isn't the flasher. The license plate light should not be hooked into the turn signal circuit, if it is correct that too.

 

[Clubtroy]

Sorry, was not clear on the issue. NONE of the turn signals work (front or rear). Nothing happens when I put the signal lever in up or down position. All hazards work after sanding the metal parts in the front signal housings and removing and retightening the light mounts through the front fenders.

I only mentioned the LP lights as I see all these posts about having enough resistance in the light circuits. The LP lights are not in the turn signals circuit.

 

[Cromagnon]

The license plate lights do not contribute to the resistance of the turn signal circuit since they are not part of the turn signal circuit.

Check the connector to the switch first. It is a good place to verify that there is voltage getting to the circuit. On the switch side of the connector you can verify that the switch is working or not with the resistance function of your multimeter. Once you have that information you can decide if you need a new switch.