Signals, flashers and brake lights out. 1970
I had an alignment done this past Saturday. I recall signaling to pull into the shop, everything working.. The car went thru a 4 wheel alignment. While it was on the rack I saw that the brake lights were on. I assume they had a fixture affixed to the steering wheel holding it straight and attached to the brake pedal. The car was on the rack for 2 hours. I assume the brakes were on that long too. Long story short, the job was complete, I paidnd drove off. As I pulled out of the parking lot I noticed the signal wasn't working. I stopped at a local parts store to and had the counter person check for brake lights. . I did. By the time I got home (9 miles) I didn't have brake lights either. I know I had B lights at the shop, I saw them. .. they were on for a long time. My question is; could something have overheated? What could have happened? I now have no flasher, signals or brake lights. I do have parking lights and reverse. I checked the fuse, it looked very strange. The filament was completely bowed to a point of touching the glass though not burnt. I changed it.. N.G. Next I changed the flasher with a plastic case one. N.G. Checked all of the bulbs. All are good. Even the green indicators on the dash are out.. The signal switch sounds good.. I've search many threads but none seem to address my problem. What could have happened? what overheated? Please help.. I can disassemble and reassemble anything.. I can fix anything.. I suck at diagnostic..
Any help is greatly appreciated.
Pete

 

Mine had a little copper box inserted to the fuse block that was getting a poor connection, heating up and tripping... It would turn off exterior lights and dash lights til it cooled down... Wiggled it in place a few times but it always felt loose... After I got it home, I pulled it out and noticed one side of the fingers in the fuse block had been pushed in/away slightly... Put a thin screwdriver in there , pried it back out to center, cleaned connections, and had no problems since... It sat right in The center of the fuse block ... But, mines an 81.. Dunno if yours has similar...

 

Thanks for responding; No I do not have the box. I just went to take a picture of it but remembered I left phone at work. They've worked for 30 years.. something must have overheated/melted.

 

Pete-

Typically the brakes are applied when the alignment is done, but I'm not sure why it would take 2 hours do do the alignment.

But.. this system is easy to diagnosis and I've posted you a simplified schematic to help you below.

In short- The brake lamps are feed power from the brake lamp switch controlled by the brake pedal. This power goes to the turn signal switch.. When no signal is on, both lamps are powered by the white wire and operate in unison. When you turn the turn signal switch in either direction, (left or right)... power for the direction turned is diverted by the switch to the flasher power side and thus the light flashes.

So.. The first thing I would check is the fuse panel. The next thing I would do is make sure power is passing through the pedal switch (B) If I had power there I would then go to the harmonic connection at the lower steering column and check for power there. Make sure this connector is plugged in good too.. If you have power coming in the switch, then make sure it's leaving on G and F.

 

Thank you sir for responding. I thought for sure "Another Signal Thread" I was in trouble. I guess the 2 hr. align was for lack of experience. The nearest corvette shop is in Newington CT "Corvette Center" and it's 50 min. away, probably should have taken the ride. Check out my thread "Alignment help"... I need to re-due. I brought specs from the AIM but they decided to use their own.. The car is all over the road at speed.
Again many thanks, I guess you just need 1 or 2 replies for the right answer. I'm sure # 1 or #2 son can follow these simple steps... NOT ME!

Thanks you,
Pete

 

Looks like yellow and green wires go to the tail, with a common wire which is brown, and a common black wire for a ground at the rear... There is a disconnect somewhere along the way...

The same common brown wire runs up to the front marker lamps which is also tied into your headlight switch/dimmer control...

There is a white wire running to your brake relay switch, which when depressed, runs power out the orange wire connecting the circuit...

The purple wire runs to your signal flasher...

And the headlight switch, turn signal flasher, and brake light switch all run to the fuse block ...

Dunno if any if that helps... But the next step it to test where you have power going in, and where you have power going out, using a test light or a multimeter...

Could all be as simple as a poor ground or bad connection at the prongs of the fuse block in the end... You never know.. Good luck!

 

Excellent instructions. Thank you for coming to my rescue. Both of my boys love cars and the electronics of them. I thought I would have a info prepared before they show up.
Many thanks, heck with these instructions I think I'll give it a shot myself.
Tks,
Pete

 

Best of luck man!

You're just looking to find where power is going in, and where power is going out... It looks like the power is supplied from the fuse block, runs through the misc components , and runs into the turn signal switch wiring harness.. I know that it's all kinda of fun trying to get to where you can see all the wiring and components in a comfortable way... But once you've located them, it's actually kinda easy to just test for power in/power out of the components...

And once the test light turns on, or doesn't... Tells you a whole lot about what component/wire to check next... Not knowing where you are or are not getting power currently, still leaves the possibility to ANY component.

So, as you get the time to look things over, definitely tell us what you find, and we can narrow down the search... That is, unless you pinpoint it and know exactly which component failed, or fuse failed , or ground failed ...

Happy hunting!

 

THANK YOU. YOU'VE GONE ABOVE AND BEYOND. I've DONE MOST JOBS, FIXED MOST ANYTHING, I JUST NEED INSTRUCTIONS. Take a look at my last post "Alignment help (pic's)". The photo's are from last yr's rad/water pump job. Resto was completed in 1993. Holding up well. Thanks again, Pete

 

I asked the shop today why lock up the brakes.. the answer they gave me is so that you can achieve a more accurate setting on the front end when setting the camber.

 

No problem bud.. Just trying to help and dealing with many similar issues in my 'new to me' 81 I bought less than a year ago...

So I'm very unfamiliar with year changes etc... Wilcox has been a treasure trove of information!

Luckily most of my issues have all been stupid simple! Lol. Just gotta research the threads here , ask a few questions , and get a game plan... Then you'll have a little time invested to find the components, then try to test them... I have had soo much success with my issues being blatantly simple once I tore into them... And all these little issues were why my PO sold the car so cheaply! So I'm very glad that I'm somewhat mechanically inclined and willing to spend the time tracking down the gremlins myself... Not to mention the satisfaction of fixing them myself!

Alignment is on my list of things to do once I tackle the front end bushings etc on mine... Perhaps I can then pick your brain! ;-)

 

Wilcox... Isn't the front rotor riveted/bolted to the hub similar to the rear rotors? Or... Wouldn't the wheel lugs hold the rotors/ hubs tight anyways? I'm just trying to wrap my head around what benefit you gain by locking up the brakes for a alignment... But hey, I'm new to this all anyways ... ;-)

 

My son # 2 is trying to diag. He said he should be able to override the brake sw or eliminate it by using a jumper wire to over ride. From his knowledge power in power out. But when he goes to jump it it sparks like it's going to ground. We have power coming out of the pink wire (flasher).. He has a power probe; can we use it to bypass the flasher? He's concerned about using a power probe and burning something out?

 

My son #2 states (referring to the brake light power in iwres, orange and white) I have power coming in from the orange... when he jumps the orange to white it sparks. He said there is a short somewhere..is this the case? is it in the sig. light sw? He said it's a simple circuit, it should not spark when paper clip is inserted.. do I need a sig lght sw located in the column?

 

My son #2 states (referring to the brake light power in iwres, orange and white) I have power coming in from the orange... when he jumps the orange to white it sparks. He said there is a short somewhere..is this the case? is it in the sig. light sw? He said it's a simple circuit, it should not spark when paper clip is inserted.. do I need a sig lght sw located in the column?

 

Looks like the white and orange wires are the ones running to the brake light switch... When depressed it breaks the connection causing the tail lights to go out... When you depress the brakes the plunger inside moves to connect the circuit and turns the brake lights on...

I'd look closer at the common ground(black wire) and the common input wire( brown) that runs through the headlight switch which turns on all the parking lights ...

Sparking on the orange to white wire is going to happen as the power from the orange tried to get to the white wire to turn on your brake lights... Just the nature of electricity... When you jumped it, did your tail lights come on? The orange to white jump should turn on your brake lights regardless of whether or not the headlight switch is turned on... So, if you don't get tail lights with THAT jump, then you've got a ground issue at the tail... Or a issue with power at the tail light bulb...

Lol... My reverse lights didn't work when I bought the car... And after checking the entire system... Pulled the bulb... And the PO installed a 1157 bulb instead of a 1156 single element bulb! Replaced the bulbs with the proper ones , and they light up perfectly!!

That's just an example of the infinite wisdom related to our previous owners... Lol. Most of my 'issues' with my car have been THAT simple to fix! Good luck tracking down your gremlins... We are getting closer!

Btw... I'm no expert, just a backyard mechanic with enough skills and experience to get myself in trouble, or occasionally win small victories... Lol. Definitely ask around for opinions and get a consensus on what others suggest to do... Make sure we are on the right track...

 

Thanks for the response: This is your statement; The orange to white jump should turn on your brake lights regardless of whether or not the headlight switch is turned on.. Not the case, nothing came on. WHEN YOU SAY "So, if you don't get tail lights with THAT jump, then you've got a ground issue at the tail...(DO YOU MEAN BRAKE LIGHTS OR TAIL? I HAVE TAIL/PARKING LIGHTS).. Or a issue with power at the tail light bulb" ARE YOU SAYING I HAVE A BAD GROUND CONNECTION OR ARE YOUR SAYING I HAVE A BARE WIRE THAT'S GROUNDING OUT? Should I look in the rear of the for the BROWN ground? I'm THINKING I MAY HAVE A MELTED WIRE FROM STAYING ON FOR SO LONG DURING THE ALIGNMENT?

 

It looks like, from the schematic... Black wire is the common ground and grounded at/near each bulb... The brown is the common power for side marker/ running lights and run through the headlamp switch to all bulbs... Yellow and green are turn signal lamps respectively...

So , if you get running lights everywhere, then the headlight switch and all brown and black wires are good...

Do you get turn signals ? That will tell you if the bulbs are burnt out or not for the second element... If you get running lights, and turn signals, then everything is correct except the power coming out of the brake light actuator switch... The one under your feet with the orange and white wires... Jumping those two should have given you tail lights...

Could pull a tail light bulb, and check to see if they burned out the light bulb... Have you done that? There's a 1157 bulb in there with two elements... I would bet that a bulb would get hot running continuously for a few hours and it could easily burn up the bulb... Last time I diagnosed my reverse lights, spent a bunch of time doing all the wire verifications... It tuned out to be the wrong light bulbs installed by the PO...

Hope some of this is helpful... Let's hear whatcha find... ;-)

 

I've had this car for 30 yrs this Oct and have logged 28k in miles.. I've never had an issue. I can't even remember changing a rear bulb. All the bulbs are good; power to the brake switch; power to the flasher; continuity to the brake switch and flasher; changed fuses; signal lever/sw solid ans firm, still clicks the same as it did..no slop in lever.
When checking the fuses I realized I had a 30amp in the direction/signal (signals died first). I'm on my way out to see if there is power going to the rear.
Summary: no brake, signal, flashers, green indicators on dash.

 

At the tail light socket... Pull the bulb, and use a light up tester to see if those wires have power... You should have it because the tail lights work as running lights... Then when you turn on the flasher, try putting one end of the tester on a ground and test the green or yellow wire to see if it gets power from the flasher...

Can basically turn the hazards on, and check the green and yellow wires for power. ;-) at the tail itself... The green and yellow wires are what supply the power for turn signals and brake lights... If you have power at those wires... Try new bulbs... Just because

Oh. The green arrow indicators on the dash aren't working either? First time I read that, I thought they were still coming on...

So, if the gree. Arrows aren't coming on, then it very well could be one of the components under the dash... Or possibly fuse... Lol. What a bunch of fun eh!