Ok, Uncle. Turn signal/hazard problems (1 Viewer)

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Ok, I call uncle.

I am at my wits end regarding my electrical system. And I know this has been covered a bagillion times before, but it seems like the symptoms can be so different and the solutions can end up different as well. Ever since I bought my FJ40 6 years ago my turn signal/hazard circuit has been messed up. The PO had an aftermarket flasher installed, and a hazard bypass wire installed so that instead of power returning from the flasher back to the hazard switch and then on to the turn signal switch it instead went straight from the flasher to the turn signal switch. I removed the aftermarket flasher but have kept the bypass, since '76 and '78 model years were wired that way but for some reason my '77 wasn't. However, my turn signals do not work at all unless my hazard switch is pulled. And when it's pulled the 4-way flashers do not go on, but I have power to my turn signals. This system worked fine until a couple weeks ago (with no 4-way flashers, obviously). I had both signals working fine, and then all of the sudden my right turn signal stopped working. Just the right turn signal. No blink, nothing. My left signal is still fine. Here is what I have found out:

-I have 8.8V at the Turn fuse. That's my first clue.
-I have 12.3V at the Stop fuse, which is the fuse power is drawn from when the hazard switch is engaged.
-My wiring diagram says that I'm supposed to have a "GR" wire coming from my Turn fuse, instead I have a "GO" wire coming from my turn fuse. Strange.
-My wiring diagram says I'm supposed to have a "GL" wire going from my flasher to my hazard switch and I'm supposed to have another "GL" wire going from my hazard switch to my turn signal switch. My hazard switch only has one "GL" wire, and I'm pretty sure it's coming from the turn fuse.
-I appear to have good grounds, because my bulbs were/are bright when connected to 12V.

Here's my path forward:
-Check the battery ground strap to the frame again.
-Check the resistance from the bulb housings to the frame and make sure the housings are actually grounded well.
-Check the voltage of the "WL" wire going into the keyswitch. And then check the voltage of the "BY" wire coming out of the "On" position of the keyswitch. I guess, just looking at the diagram, that I have some sort of bad voltage loss across the keyswitch. What can be done to remedy this? Does it automatically mean I should be looking for a new one? Or maybe I have a loss across the ammeter, in which case I need to figure out what's going on there.

Any other ideas or things to check? Just seems like being methodical is going to be my best bet.
 
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The PO had an aftermarket flasher installed, and a hazard bypass wire installed

However, my turn signals do not work at all unless my hazard switch is pulled. And when it's pulled the 4-way flashers do not go on, but I have power to my turn signals.

-I have 8.8V at the Turn fuse. That's my first clue.

My wiring diagram says that I'm supposed to have a "GR" wire coming from my Turn fuse, instead I have a "GO" wire coming from my turn fuse. Strange.

-Any other ideas or things to check? .

1. It would be a good idea to remove or at least understand the aftermarket flasher wiring as this could be the problem. What is a hazard bypass wire? The closer it is to stock wiring the easier it is to understand for someone that can't be there to look at it.

2. When the hazard switch is pulled out, power is supplied to the flasher and all 4 lamps. There is something wrong with the wiring if it doesn't work that way and it may be related to non-OEM wiring in 1 above.

3. Wiring colors change with time, so I wouldn't presume it is wrong. Verify where the other end of the wire ends up as predicted by the schmatic diagram using your ohm meter with the wire ends disconnected.

4. Start by putting battery power on to the GL wire at the flasher with the hazard switch off (in). If the turn signals don't work there is something wrong downstream from the flasher, meaning the turn signal switch and wires to the lamps, etc.

5. Which side of the turn fuse? If it is the side down stream from the battery, then the fuse may be bad.
 

Rockets2000

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Agree with Pin_Head. Also, clean your fuse holders on the fuse block and replace the turn signal fuse, if not all of them. There should be no need to get into the key switch other than to check voltage from the ON position. I would also replace the flasher unit.
 
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1. It would be a good idea to remove or at least understand the aftermarket flasher wiring as this could be the problem. What is a hazard bypass wire? The closer it is to stock wiring the easier it is to understand for someone that can't be there to look at it. The aftermarket flasher is gone. I will return the wiring back to stock to continue with diagnostics. If you look at the wiring diagram for a '76, you will see that the "GL" wire going from the flasher back to the hazard switch splits and heads directly to the turn signal switch. I basically replicated that, since a stock '77 doesn't do that. But I will take that out and start over

2. When the hazard switch is pulled out, power is supplied to the flasher and all 4 lamps. There is something wrong with the wiring if it doesn't work that way and it may be related to non-OEM wiring in 1 above. Agree.

3. Wiring colors change with time, so I wouldn't presume it is wrong. Verify where the other end of the wire ends up as predicted by the schmatic diagram using your ohm meter with the wire ends disconnected. Yep, the reason I mentioned the different colors/configurations is because I had a thought that maybe I have a different year wiring harness in there from a PO. But maybe not, wouldn't be the first time the FSM is wrong.

4. Start by putting battery power on to the GL wire at the flasher with the hazard switch off (in). If the turn signals don't work there is something wrong downstream from the flasher, meaning the turn signal switch and wires to the lamps, etc. Good idea, I'll try that.

5. Which side of the turn fuse? If it is the side down stream from the battery, then the fuse may be bad. I tried both sides of the fuse to make sure, reading was the same on both sides.
Agree with Pin_Head. Also, clean your fuse holders on the fuse block and replace the turn signal fuse, if not all of them. There should be no need to get into the key switch other than to check voltage from the ON position. I would also replace the flasher unit. I will check to make sure my fuse holders are clean, but I don't see a need to replace the OEM flasher because it works just fine.
Thanks! :cheers:
 
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Yep, I've had it apart a couple times. Everything seems nice and clean inside. I was just looking back over some notes I have from a few years ago when I was looking into this, and I think I may have identified a couple potential problem areas I need to look at. Will try to check them out as well and see if I can figure out what's going on...
 
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Sounds like you're in good hands with the previous posters. What I can suggest to help clean your contacts is to stop by a paint/body supply shop and pick up some 3M Spot Sanding Pens. Get a few, they are cheap and wear out quicker than you would think. Think of rolling fiberglass fibers out of a capri cigarette diameter sized chapstick.

Very handy to shiny up hard to reach spots. Much better than pencil erasers.
 
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What part of Denver are you in? I may have some free time on Saturday morning (if photo gig falls through) to assist as I just went through this on my '73.
 
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Thanks for the offer. I'm thinking I'll only be able to address this issue a few minutes at a time, and I'll probably be gone most if not all of the weekend. Since this isn't a daily driver I'm not in a huge hurry to get it fixed. I'll just chip away at it a little at a time. :cheers:
 
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-I have 8.8V at the Turn fuse. That's my first clue.
-I have 12.3V at the Stop fuse, which is the fuse power is drawn from when the hazard switch is engaged.
If you take out the Turn fuse, does the voltage at the hot side go back up to 12.3v? If so, you have a short, but I would expect you'd notice the dead battery before now. If not you have resistance between that input side and the battery. If so, run a jumper directly to the battery and see how the system works. If that helps, cut out the bad circuit and make the jumper permanent. Bad fuse block?
 
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I know it has already been posted, but I will echo: Clean the fuse block & replace the fuses!

Almost all of the 'weird' electrical problems I once had on my cruiser were cured by paying attention to the fuse block.
 

Cruiser804

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I know this sounds over simplified but try changing all the marker light bulbs. I had a similar issue and what I found was that the majority of the bulbs were the original Koito bulbs. All were lighting as expected but my turn signals would not work when the lights were on. I supposed the combined resistance or the old bulbs wasn't allowing enough current to the flasher.

I know your circumstances are different but...10 bucks and half an hour.
 
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Okay, after doing a little testing and diagnosing today I found a couple potential problem areas:
-I thought my hazard switch was fine, but after going through the FSM checks I am still having problems. Going to try and fix that tonight. I am not getting continuity between all the pins that I'm supposed to be getting continuity on at different switch positions. It also looks like a couple pins overheated at some point and melted the plastic in the connector and it got on some of the pins. EDIT: got my hazard switch sorted, all seems well with it now.

-EDIT: my turn signal switch had continuity when it was supposed to, by checking against the test of the FSM, so I'm pretty confident that it's in good shape. I do have a problem with the turn signal switch connector though. My FSM shows a 6-pin connector for the turn signal switch. One the side of the connector attached to the switch, there are 6 wires coming in. On the side connected to the harness, there are only 4 wires. Do some wires combine within the connector or am I missing those two wires coming out of the connector? See these photos (colors may be wrong):



-On the turn signal switch, there is a wire labeled "SS" in the FSM. This wire is green and white and has a male bullet connector on the end. It's supposed to go to the "Stop light switch (power source)", but I cannot find a female bullet connector under the dash to plug it to. The stop light switch doesn't have a matching connector. Help?


-I cleaned up my fuse block, checked my fuses and continuity, and applied power to the "GL" wire coming out of the flasher with the hazard switch off. With the turn signal switch in the "left" position, the left lights go on and stay on. With the turn signal switch in the "right" position, I get nothing. So I must have problems with my wiring on the right side. I'll have to trace that down, I guess starting just below the turn signal switch by applying power to the "GY" wire.

Anything else?
 
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BTUMAN

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Not sure of much help, but my side markers where not working on my new to me 1978 and I started digging into it. Found both bulbs original and gaulded to the connector and one wire broke. When I traced it back to the drivers rear turn I found the connector melted and wire bare and meshed together. I don't even know how the rear lights were working! I mean all 4 wires were bare, the connector melted and I still had reverse, brake and parking lights. So I think the other user is correct in checking all the connectors. Could be a short inside or melted wire, etc.
Connector.jpg
 
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Not sure of much help, but my side markers where not working on my new to me 1978 and I started digging into it. Found both bulbs original and gaulded to the connector and one wire broke. When I traced it back to the drivers rear turn I found the connector melted and wire bare and meshed together. I don't even know how the rear lights were working! I mean all 4 wires were bare, the connector melted and I still had reverse, brake and parking lights. So I think the other user is correct in checking all the connectors. Could be a short inside or melted wire, etc.
BTUMAN, that shackle looks over-tightened and/or missing a bushing.

Hi-jack over...sorry
 
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Okay, after some more diagnosing I found out some more:
-Cleaned up hazard switch made no difference, so the problem isn't there. I now know the hazard switch is working correctly, but there is some other issue in the wiring that is keeping the hazard switch from performing its proper function.

-I checked my ignition switch and it has good continuity and low resistance (1-2 ohms between pins) at the various positions.

-I checked the turn signal switch again because I missed something when I checked it last; sure enough the FR pin is not getting continuity like it's supposed to. I will have to look into that in more detail.

-I really need to find out where the "GW" wire with the male bullet is supposed to go (the FSM doesn't show a connection to this wire in the picture of the Stop light switch); I think this is part of the reason why the turn signals will not work unless the hazard switch is pulled. But I still do not get why the 4-way flashers won't work with the hazard switch pulled. My guess is it has to do with the connector I posted a picture of above; what's going in to and coming out of that connector does not match the FSM, which I don't get because I don't see snipped wires or anything in the vicinity. It all looks stock. Argh.

Another thing; I put power to the "GY" wires coming out of the turn signal switch connector (there are two, see picture above). The one labeled "FR" in my FSM made the right dash turn signal light, front right turn signal light, and rear right turn signal lights go on. The other one goes to the horn switch, and is "GR" on the wiring harness side. The pin connection labeled "RR" in my FSM has a "GO" wire going into it on the switch side and nothing coming out of it on the harness side. So I guess all the power for the right side bulbs goes through the one "GY" wire. And I have no idea what the "GO" wire goes to - it doesn't exist in the wiring diagram.

My first issue to solve will be to get reliable power to my right turn signal bulbs. This appears to be a problem in the switch. If I get power to the "FR" pin in the turn signal switch connector then that will provide power to the right turn bulbs.
 
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Sorry, I am not familiar with the plug.

Since the turn signal lights come on when you put power directly on the G/L wire, the switch on one side works. There is a problem on the side that doesn't work at or after the switch. Put 12V directly on the other side of the flasher and the turn signals should flash if the flasher is good. If it doesn't light, flasher is bad.

G/W wire is the main power feed for the hazards going from the hazard switch to the stop lighht fuse. If you can't find the other end of this connector from the switch, start at the fuse block and follow the G/W wire in the other direction. Also note that the same color code wire connects to the brake light switch and the fan timer, so maybe you have the wrong one of the G/W wires.
 
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I believe my problem with my right turn signals not lighting is in the turn signal switch. I will investigate further hopefully this afternoon. I believe the flasher works fine because my left turn signals blink just fine.

"GR" I believe is the power feed from the "Stop" fuse to the hazard switch. As the power continues from the hazard switch to the flasher, the wire becomes "GW."

But there is another "GW". It is not shown on the wiring diagram, but is shown in the pictorial for the turn signal switch in the FSM - labeled "SS" with a male bullet connector. It's supposed to go to the brake light switch. I inferred its color because I have a wire with a male bullet connector under the dash - but it's not connected to anything. I also understand that the power going from the brake light switch to the rear bulbs is a "GW" wire also. This one *should* be different from that one as well.

I'll start with fixing the turn signal switch and then go from there.

Pin_Head, I really appreciate your input. Right now I am needing this space to write down my thoughts and bounce them off of people who have experience. Hopefully with enough rambling and chasing down wires I will find the solution to my problem. :cheers:
 
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I sold my 40, so I can't go out and look; I can only look at the schematic.

The green/red is the power feed for the turn signals that is only hot with the key on. The G/W is the power for the hazards that is always hot, hence the need for two fuses and two power sources.

The hazard switch has two functions. It selects which power source powers the flasher and in the hazard mode, it sends the blinking output of the flasher directly to the lamps bypassing the turn signal switcch.

The flasher terminals should always be hot with the key on and the hazard switch in or off. If not you have a problem with a bad connection in the hazard switch or fuse block. If you then turn the turn signals the lights should come on or flash. If not check the voltage at the flasher. If it is zero, there is a bad connection before the flasher, in the hazard switch or at the fuse block. If it is battery voltage, then there is a bad connection downstream from the flasher, like the turn switch or the lamps.

Look at the schematic diagram for the '78 cruiser in tech links. It is close enough for you to tell how the hazards/brake lights are wired. They use the same color code on a common circuit.
 
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Turns out my Haynes manual has had better info than the FSM on details of the wiring diagram. I have compared the wiring diagrams for '76, '77, and '78 in the Haynes and see some subtle differences. My FSM has the wiring diagram for a '79 (inconvenient since I supposedly ordered an FSM for a '77), which also has some more differences. According to Haynes, a '77 should have a "GR" power from the "turn" fuse for when the hazard switch is "off" and a "GR" power from the "stop" fuse for when the hazard switch is "on." Instead, I have found that I actually have a "GO" power from the "turn" fuse for when the hazard switch is "off." But that really is neither here nor there, the color of the wires is somewhat immaterial (though inconvenient when it doesn't match the wiring diagram) as long as the path for electricity to flow is completed.

I'm slowly pulling all the info in the FSM together - connector pin continuity, wire colors, etc. I think I have a pretty good understanding of how it's SUPPOSED to work, but I'm having trouble finding out why MINE doesn't work, even though it seems to be hooked up correctly. I'll start with the turn signal switch and then deal with any other problems as they come up in the diagnostic process. :cheers:
 

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