Tail lights not working?
 

I've got dash, brake, headlights and turn signals all working, but no tail lights.
Where do I look first?
1968 912
Thanks

The pressure sensing switch on the master cylinder has most likely gone bad. Easy fix, do a search and your questions will be answered.

Go give all your fuses a twist.
Ck for continuity too .

I suggest starting simple and checking that both bulbs are making contact for the tail light and brake light function. Easy to do. If the bulbs are at all loose it can cause the issue you are describing. The contacts in the socket can be less than tight due to a weak design(IMHO). I had the same issue and assumed the switch on the master cylinder was the issue but checked the bulbs first and they were moving in the poorly designed socket. If the bulbs and contacts are fine, then the switch would be the next potential culprit. I had to use a fix I found here on the board of adding solder to the 2 bulb contacts and then filing back for a tight, solid fit. Fixed my problem. Good Luck

Check the wiring at the fuses up front. Fuses are good if your front running lamps are on. The front and rear running light wires are doubled up on the same terminal.
After that it could be loose sockets. Also try wiggling the 6 pin socket by the rear motor mounts n each side.

+1 check bulbs/socket are clean. Just went thru this, with front turn signal flashing but nothing on rears. Easy 1st check is to remove lens and wiggle bulbs with emergency flashers on.

I would also check the micro switch at the brake pedal. Make sure there is power going to it which would verify that all fuses are good.

I checked the bulbs, they seem to be seated properly. Didn't get to the brake light switch yet....it's freezing out!!!!
Just put a new master cylinder in a week ago.
Fuses and wiring at fuse box look good.
Couldn't find a 6 pin socket anywhere near motor mounts?

No 6 pin sockets on your 68, sorry, I read a different year in your signature.

Out of curiosity, what does the brake light switch have to do with tail lights? Is it a 2 phase bulb?
And in doing research I see two kinds of switches, one on the pedal cluster, that I do not recall seeing on my car before I put the floor boards back in, and another on the master cylinder. Does a 68 swb have both? There is very little info out there on this stuff, or I'm searching the wrong thing. Thanks

http://uploads.tapatalk-cdn.com/2016...5ac367fb69.jpghttp://uploads.tapatalk-cdn.com/2016...b6005d5538.jpg

Ok, I'm way out of my league here. Obviously this car has been through the ringer over the years and it's been hacked up and rigged. I took the floor board off this morning hoping to find a loose wire on the switch.... Above is what I found, ...lots of unconnected wires. Some in the back too.
I have no idea where any of this stuff is supposed to be hooked up.
All fuses are ok, dash lights work, head lights work, turn signals work, brake lights work.
Rear tail lights are out. Front running lights are out.
Also, somewhere in its life, the windshield washer system was yanked, and there is NO emergency flasher switch (and of course those are like finding hens teeth).
Thanks in advance for any help you can offer.


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Anyone? Bueller.....
Is it that bad? You're afraid to tell me it's terminal?
Was it something I said? I'm so insecure!!! Someone say something!!!! :D

First of all, don't panic. Many have had the same experience with hacked wiring and sooner or later, things will come together.

Ignore the posts about your brake lights or brake switches as they are not related to the running lights. Even though you have a dual element bulb, the wires to that bulb that power the running lights is not related to the brake light switch.

Note the bold in your post, that gives you some clues. Dash lights work but are not on fuses. Headlights work so those fuses are good. Brake lights work and turn signal lights work so that fuse is good as is the brake light switch. The only circuit that is not working is for the running lights--fuses 7 and 8--but how do you know the fuse for the running lights is good? You did not make that clear. Visual checks are not adequate.

You need to start testing, using a test light. Start by turning on the light switch and checking both sides of the fuse at terminals 7 and 8. Do you get a light on both sides of the fuse?

At this point, I'd suggest you perform the above check and report back. Electrical issues, especially, require a lot of feedback so we'll wait until we know what you're dealing with.

One step at a time.

Oh yeah, all the above advice is moot if your wiring has been seriously hacked so lots of good clear pictures may be necessary. Be prepared.;)

Refer to this wiring diagram for your '68

http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_1965.jpg

Thanks Ossi!
Ill test and I'll report back later today or tomorrow.

Ok, so it was late, dark and REALLY cold last night but I hooked up the tester ground clip to the battery neg, turned the key on and touched the brass terminals on both sides of the fuses...nothing.checked a few other random fuses and contacts....nothing. Thought maybe the tester was shot so I touched the pos on the battery and it lit up so it's working. Thought maybe, (why, I have o idea) that the car needed to be running so I got it to to over.....stall...then died trying to start, so the battery is weak and needs charging or replacing. But that doesn't explain no juice to the fuse box.
Headlights worked though. Do the running lights and reverse lights, run through the headlight switch first? Meaning does the battery's power go to the switch and THEN to the fuse box?

Also-
I think I may have mentioned already there is no emergency hazard switch. I'm starting to get the feeling that has something to do with the hack job wiring. Whoever did it must've had to work around flasher switch absence. Being that they are year specific and NLA has anyone had to deal with using another modified switch?

Take a look at the wiring diagram.
Battery power goes directly to the switch from un-fused terminal at fuse 2 to terminal 30 of the light switch (34). The fact you apparently have dash lights when you pull the switch means that it is working.(getting power)
The grey/red and grey/black wires get power through the switch contacts when activated and go through a grey colored 8 pin through dash connector back to the fuse panel terminals/fuses 7 and 8. The connector may be loose or corroded, the fuse panel connection may be the same.
They should also be activated with the ignition off and operating the turn signal either up or down to turn on the "parking light" feature for Europe. (same wires running to blinker/dimmer...
item (32)

Thanks Timmy!!
I am going to sit and try to absorb the wiring diagram better tonight. I'm not very experienced with wiring AND my eyes suck, so I'll need a bigger screen than iPad :)


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Print it and grab a magnifying glass. :)

http://uploads.tapatalk-cdn.com/2016...4fb2f46100.jpg
And readers too!!!
Ok, this looks relatively 'followable'. Now I have to wait for a little warmer weather and get the battery charged/replaced.


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http://uploads.tapatalk-cdn.com/2016...e201a644e0.jpg

Ok, got the battery charged and here is what I have - the fuse box pic with the "Y"s and "N"s refer to "Y" has power and "N" does not.
So it looks like power is coming through the headlight switch to the fuse box but not getting to the lights. I DO get power to the front passenger side running light.
Also, while fiddling around the relay circled came loose. It looks like some one rigged a relay to replace the original? There seems to be a plug for a relay that the one pictured was modified to replace.There are two connections running from the circled relay to the plug, a spade, which fits snug, and a clip to a spade that the wire came out of. I replaced the clip and put it back on but now the turn signals don't work anymore, that's why I'm assuming it's a rigged turn signal relay but I could be wrong.
Should all the fuses have power coming and going (aside from the aux heater)?
Thanks


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Power in one side of the fuse and none on the other normally indicates a bad fuse or fuse holder.

I guess we're on to taking the fuse box out and cleaning and checking terminals. If it's shot, I can get one for $50 from our host.
Any idea what that rigged relay is?
I can't find a picture of what that area on a 68 912 is SUPPOSED to look like or what is what. I think I saw one pic that labeled in headlight relay, which doesn't explain the turn signals suddenly stop functioning after the wire came loose. I tried to repair it and crimp q new clip on but it's signals are still not working. Whatever the green wires are connected to seems to be a plug, or was at some point, seems like if it's for a relay the relay should be plugged into and not wired to it.
My hopes are to get the car wired back as close to stock as I can.
I have no idea what the wires behind the pedal cluster in pic above are for yet.
Not sure how close to stock I can get without the NLA hazard switch either.
Any guidance and or direction is greatly appreciated.

Pm or email me a phone number and a good time to call (I'm on the west coast)and we can discuss what may or may not be right or wrong with the wiring. Trying to troubleshoot wiring in a forum environment really sucks... :)

Pm sent. Thank you!!!

My brake lights stopped working shortly after replacing all the bulbs in the car. I was disturbed because the old bulbs worked fine but my OCD caused me to change them all to new.

I decided to put back the old brake bulbs but they no longer worked either...

Turns out that the copper contact that the bulb rests on needed to be pulled out slightly. I suspect that after many years of being compressed, it just lost it's spring but it has worked fine ever since.

One step forward, one step back….. So I have done some digging, the fuse box has been rewired to some extent. Haven't had the opportunity to trace the mis-colored wires yet, but I did get to the front and rear lights. All but the drivers side front light still have the original color coded wires, the drivers front has been rewired using some blue and some white wires. Good news, I now have front running lights. The rear lights are really F'd. I get brake lights (very weak power to them, they barley light up), not running lights, and the reverse lights don't work either, but when it's in reverse I get the driver side tail light….which is weird to me because they all have the correct wires running to them. So I'm assuming it's somewhere going from the fuse box (which does seem to be still in tact for the running lights fuses 7&8) to the lights themselves.
I will continue to explore tomorrow.

Since I got my car in early December it's been sitting at my buddy's shop and I've doing what I can as time permits, and my buddy has as well. So I got a text from my buddy this morning asking where the wiring diagram was. I told him it was in the trunk, by the time I got there this afternoon he had all the lights working. Sweet!!!(but I kinda wanted to help so I could learn) I asked him where the wires were screwed up and he gestured from the front to the back of the car.
Soooo, good news in that I have a functioning road legal car for now.
We went to put in a new generator and regulator and when I opened the box.....wrong generator :(