loup68

I just realized by my fiber optic monitoring ALL four 68 tail lights, that the brake lights do not work. I managed to get my turn signals working after replacing a burnt out front turn signal bulb. They also work with the headlamps on, however one bright headlamp will not light and the connector is clean and the bulb is not burnt looking. Very strange. Not only do the brake lights not come on, my 4-way flashers do not work at all. I changed the flasher, and they still do not work. When I put them on, only the front two lights light up, not the back lights.
The side marker lamps will come on with the parking and head lights but will not flash with the turn signals. I checked my junk yard find 69-up brake light switch, that I changed 35 years ago,and it still works. Like I said, the lights in the rear work with the turn signals, but not with the brake light switch. I hope that Willcox can help me, I am not an electrician!.
Thank you, Lou.

wombvette

First off check the fuse. The fact that the turn signals work, should discount a ground issue.

On the front, you probably have a bad bulb. They do not necessarily have to look smoked to be bad.

loup68

Wombvette, I did replace the fuse and cleaned the rear lamp ground screw. From the 68 wiring diagram, both the 4-way flashers and the brake lights get their power from the same place on the fuse box. I cannot figure out with the wiring diagram, where the power comes from to feed them. I may try to take apart the bulk head connector.

7T1vette

The headlamp fiber optics get their light from the little sealed 'tit' (sorry for the colloquial jargon) on the back of the bulb. Some new bulbs are painted or silvered at that spot and no light can reach the optic fiber in the electical connector. Also, the original headlamps had a little black plastic tube installed between that electrical connector and the bulbs. These are usually lost after the first bulb changes on the car. I replicated what was originally there on mine with a short length of 3/8" black shrink tubing.

0Willcox Corvette

Power goes to the brake lamps from the turn signal switch. The picture below is almost the same as your car.. the switch is different and the colors may be different but the system works in the exact same manner.

Since your turn signals work you may want to check the brake lamp switch for power going in, and then out when depressed first. If you have power coming out of the switch then go to the turn signal connector and see what you have there.

I just helped someone else with a similar issue but the advice ia basically the same for you.

http://forums.corvetteforum.com/c3-t...t-working.html

loup68

Willcox, Thank you for answering. I did read that post yesterday and your information is very helpful. I also down loaded your 68 switch testing article.
I bought a circuit tester and found out that I do have power at the brake light switch. I disconnected the turn signal switch connector and found a couple of the terminals were too low. I had removed them almost 30 years ago to get them through the retainer on the 68 column. I had to super glue two to keep them from moving backward. When I replaced the connector, and tried it, I now have the front two turn signals flashing with the 4-way flasher. Still no brake lights. The problem has to be in the turn signal switch, right? After the switch, the power goes to the back lamps. I will have to order a switch.

0Willcox Corvette

Is the power coming out of the brake light switch? Make sure of this (I usually suggest a jumper for testing...

If you have power coming out of the switch.. then go to the connector at the column. Now I have what I call a Pin probe but it's just a standard electrical tester that I filed a very sharp point on so you can do the same... But the idea behind this is to pierce the wire and test right before the connection terminal and right after. This will tell you if you have power passing through. So do this to that white wire before the connector and after... If you have power on both sides then you should (with the switch jumpered) have power on both green and yellow... again.. before and after so test both just as above. If you have power in and nothing out they yes.. it's the switch.

But you should test these things before you ever pull it out. If you have already had terminal problems and had to glue them then make sure it is not a problem now.

Willcox

loup68

Again, thank you, Willcox. I did have power at the brake light switch. Today I used your new directions and I have power on both sides of the white wire, but nothing on both sides of the green and yellow wires at the column connector. The turn signal switch has to be bad. I was able to probe the connector metal contacts without piercing the wires.I can not thank you enough for helping me find the problem. I never would have thought that the brake light switch power then goes to the turn signal switch. But it does make sense. You are a valuable asset to this forum. Lou.

0Willcox Corvette

Thank you Lou.. but guess what.. were not done testing.

Since you think this is your problem.. Jumper the power from the white wire to the green and yellow.. this will let you know for sure the lamps are working properly.. if this happens then you have 100 percent confirmed the switch to be the issue.

Have a great weekend..

Willcox

shmoky

Mr. Willcox comes thru again. That's why we love you so much Ernie.
and I mean that in a good/straight way

shmoky

0Willcox Corvette

Thanks Shmoky... I'll call it passion.. 68's seem to be the "Scarey" car... I ain't feared.. LOL.. You have a great weakend..

loup68

I just tried jumpering from the white wire to the yellow and green wire, separately, on the turn signal side of the connector. Jumpering to either the green wire or the yellow wire, made all four tail lights light up. Is that normal? I did not try jumpering both wires together. It looks like it is the turn signal switch, for sure. Lou.

loup68

I changed the turn signal switch and everything works now. It is wonderful to have brake lights, again. If it was not for having my fiber optics ( on all four 68 taillights ), I do not know how long it would have taken me to realize that they were not working. When I first got my 68 over 40 years ago, I felt that the fiber optic monitoring should be standard on all cars and I still feel that way. Thank you Ernie at Willcox and to Jim Shea's paper on changing the 68 turn signal switch. I did not have to pull the wires out of the connector this time to change the T/S switch. Lou.

0Willcox Corvette

Good Deal Lou... I'm glad you got her working again..

loup68

Ernie, at Willcox, Ecklers sent me a new catalog and I happened to notice that they have a 68 turn signal switch, actuating cam replacement. It is part number 49920, on page 171 in the catalog.. Did you know about this part and have you ever tried to use it? My original switch had one of the plastic pieces break off, and I had to replace it with the one that just died. Lou.

0Willcox Corvette

Lou- I'll have to check this out for you and message you back..

Update: Lou from what I understand the complete switch is due soon.. I've never used or installed this item, it has been added to our site though. http://willcoxcorvette.com/product_i...ducts_id=27669