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-   -   Brake light gremlin is back (https://67-72chevytrucks.com/vboard/showthread.php?t=862148)

1970 CST Short Wide 12-26-2025 11:43 PM

Brake light gremlin is back
 
Before I put a NEW wiring harness in my 70 my driver side brake light would work when it felt like it. One day yes next day no. Anyway my Son and I put a WHOLE NEW HARNESS from American Auto Wire ($763) in and everything worked Perfect. We even put some new grounds in like Cab to Frame, Bed to Frame. Engine and battery were already grounded to frame

After a month of working perfect IT CAME BACK. I’m about to lose it

MikeB 12-27-2025 12:37 PM

Re: Brake light gremlin is back
 
1157 dual-filament bulb, right? If so, does the turn signal for that side also work intermittently?

1970 CST Short Wide 12-27-2025 02:32 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by MikeB (Post 9416227)
1157 dual-filament bulb, right? If so, does the turn signal for that side also work intermittently?

Yes 1157 bulb. I haven’t looked at that. Good ? I know that when it’s working everything works tail lights and signals. I’ll have to watch for that. So if it doesn’t work ????

MikeB 12-27-2025 05:14 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by 1970 CST Short Wide (Post 9416244)
Yes 1157 bulb. I haven’t looked at that. Good ? I know that when it’s working everything works tail lights and signals. I’ll have to watch for that. So if it doesn’t work ????

The same filament is used for brake and turn signal. It could be the bulb socket or wiring or a connection along the way from the flasher to the back. But I suspect it would be something you didn't replace.

WorldsCrappiestTruck 12-27-2025 10:27 PM

Re: Brake light gremlin is back
 
1 Attachment(s)
Swap the metal taillight housing from one side to the other and see if the symptoms move.

My ‘68 had a dim taillight which turned out to be a high-resistance connection between the metal cylinder that the bulb attaches to…..and its crimp to the main taillight housing which acts as the actual ground path to the bed (red arrow). Similar - this was day 1 after a new AAW harness.

Bought 2 new aftermarket taillight housings and the lights are now perfect.

You may just have impossible-to-see corrosion between that crimped connection.

RustyPile 12-27-2025 10:38 PM

Re: Brake light gremlin is back
 
The turn signal switch is deeply involved in the brake light circuit. Since the brake light filaments share duty with the turn signal filaments, the turn signal switch has to separate these circuits.. The dark green wire provides power to the right-rear brake/turn signal..

When the failure is occurring, back probe the dark green wire on the turn signal harness plug at the column. If voltage is present, there is an intermittent open somewhere in the harness between this plug and the bulb. If no voltage is present, the turn signal switch is faulty.

1970 CST Short Wide 12-28-2025 12:05 AM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by MikeB (Post 9416261)
The same filament is used for brake and turn signal. It could be the bulb socket or wiring or a connection along the way from the flasher to the back. But I suspect it would be something you didn't replace.

Every wire and switch has been replaced brake light switch, ignition switch even the dimmer switch. New fuse box has New Flashers. New tail lights and housings and of course New bulbs. I’m sure it’s a bad ground / connection I just haven’t found it yet. The frustrating part is it returned after I replaced everything To Fix It

1970 CST Short Wide 12-28-2025 12:06 AM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by WorldsCrappiestTruck (Post 9416278)
Swap the metal taillight housing from one side to the other and see if the symptoms move.

My ‘68 had a dim taillight which turned out to be a high-resistance connection between the metal cylinder that the bulb attaches to…..and its crimp to the main taillight housing which acts as the actual ground path to the bed (red arrow). Similar - this was day 1 after a new AAW harness.

Bought 2 new aftermarket taillight housings and the lights are now perfect.

You may just have impossible-to-see corrosion between that crimped connection.

The housings for both tail light and back up light are New

Steeveedee 12-28-2025 12:53 AM

Re: Brake light gremlin is back
 
I didn't see where the turn signal switch was replaced. I'm not blaming it, but if everything else has been replaced...what is left?

1970 CST Short Wide 12-28-2025 08:37 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by Steeveedee (Post 9416291)
I didn't see where the turn signal switch was replaced. I'm not blaming it, but if everything else has been replaced...what is left?

That’s a Good point. I’ll be checking that Next for sure, thanks

Stanco 12-30-2025 12:18 PM

Re: Brake light gremlin is back
 
With the brakes applied work the turn signal switch and see what happens. Put the back of the truck near a wall and observe the lights in the rear view mirror.

RustyPile 12-30-2025 05:49 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by Steeveedee (Post 9416291)
I didn't see where the turn signal switch was replaced. I'm not blaming it, but if everything else has been replaced...what is left?

Thank you sir.. For some strange reason shortwide didn't read and/or see my post.

1970 CST Short Wide 12-30-2025 06:50 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by RustyPile (Post 9416280)
The turn signal switch is deeply involved in the brake light circuit. Since the brake light filaments share duty with the turn signal filaments, the turn signal switch has to separate these circuits.. The dark green wire provides power to the right-rear brake/turn signal..

When the failure is occurring, back probe the dark green wire on the turn signal harness plug at the column. If voltage is present, there is an intermittent open somewhere in the harness between this plug and the bulb. If no voltage is present, the turn signal switch is faulty.

Sorry I guess I did miss your post. Definitely something to look at. I appreciate the input
The more I think about this one the more I suspect it

1970 CST Short Wide 01-03-2026 03:50 PM

Re: Brake light gremlin is back
 
Thank You RustyPile. This is what I Love about this site. You present a problem and people respond, my bad for missing your post but Guess What, that was it. If I put on the brakes and then the turn signals right after they cancel the left brake light stops working. Turn the signal back on and you get brake light. If you just turn off the signal without turning the wheel the brake light works. Definitely will replace turn signal switch but also thinking New column as this is an Auto Tilt Column and I now have a Manual trans

Once again thank you and everyone else that gave input.

Anybody have suggestions on a Manual Tilt Column

MikeB 01-03-2026 04:56 PM

Re: Brake light gremlin is back
 
Way to go Rusty! Say hi to your brother Gomer.;)

WorldsCrappiestTruck 01-04-2026 09:35 AM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by 1970 CST Short Wide (Post 9417070)
Anybody have suggestions on a Manual Tilt Column

I bought one off eBay for a seller JL Fabrication, who seems to be a generic reseller of imported parts for my ‘68. Before doing so I’d researched a lot and found some internet horror stories about “anything except a Flaming River uses plastic parts inside and is subject to falling apart, leaving you unable to steer”

One school of thought is “why scrimp on a steering column that’s so important - buy the flaming river for $1300 or so.”

The other is “there are oodles of folks using this type of column and I haven’t heard a real-world example of one falling apart, so try it out and hope for the best.”

I’ve driven mine 11,000 miles with 275 tires and manual steering…and have cranked on the wheel awful hard in parking lots etc - nothing seems to be coming loose or seems like it’s failing.

Your results may vary…?

(Attempted to paste in the link but it just keeps launching a blank page - maybe poke around on eBay - I think most probably come from the same factory overseas and are resold by eBay sellers)

Getter-Done 01-04-2026 01:10 PM

Re: Brake light gremlin is back
 
Summit has this steering column.
Link: https://www.summitracing.com/parts/FLA-FR20007-36BK

Jegs has these.
Link: https://www.jegs.com/webapp/wcs/stor...nnelSource=WEB

sellersrodshop 01-04-2026 01:34 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by 1970 CST Short Wide (Post 9416285)
The housings for both tail light and back up light are New

I just did a complete wiring harness on another vehicle and changed some old housings out for new. Believe it or not, over half of them didn’t work properly from the get go for various reasons. Not grounding properly from socket to housing and the spring loaded “plate” with the contacts in the socket not hitting the contacts on the bulbs seemed to be the major issues I found. Took a lot of testing and sorting out to get them right as I would remove a bulb and hit with a test light and everything would work, put the bulb back in and no go.

MikeB 01-04-2026 01:45 PM

Re: Brake light gremlin is back
 
Not sure how this subject has made its way onto this thread, but here's something you absolutely must read before buying an aftermarket steering column. It's a 2013 article, so some of the cheapies may be safer now, but I wouldn't bet my life on it. Scary stuff!

https://www.lvvta.org.nz/documents/i...ng_Columns.pdf

The only aftermarket column I've had experience with was an Ididit in a 55 Chevy car I had just purchased. It was a few inches too long for me, so I sent it to Ididit to have it shortened. They charged me $50 including return shipping, which I thought was more than fair.

But here's the main thing: When I got it back, I realized they had installed several new parts, including a new turn signal switch. When I called to thank them, the guy I spoke with said since was all apart they decided to rebuild it under their lifetime warranty! It's probably the most impressive service I've ever received from a vendor/manufacturer.

sellersrodshop 01-04-2026 06:13 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by MikeB (Post 9417217)
Not sure how this subject has made its way onto this thread, but here's something you absolutely must read before buying an aftermarket steering column. It's a 2013 article, so some of the cheapies may be safer now, but I wouldn't bet my life on it. Scary stuff!

https://www.lvvta.org.nz/documents/i...ng_Columns.pdf

The only aftermarket column I've had experience with was an Ididit in a 55 Chevy car I had just purchased. It was a few inches too long for me, so I sent it to Ididit to have it shortened. They charged me $50 including return shipping, which I thought was more than fair.

But here's the main thing: When I got it back, I realized they had installed several new parts, including a new turn signal switch. When I called to thank them, the guy I spoke with said since was all apart they decided to rebuild it under their lifetime warranty! It's probably the most impressive service I've ever received from a vendor/manufacturer.

Not sure who owns Ididit as I’ve been out of the street rod world for 20 yrs now, but back in the 90’s I knew the owner and most of the employees and all were stand up folks.

RustyPile 01-04-2026 06:55 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by MikeB (Post 9417082)
Way to go Rusty! Say hi to your brother Gomer.;)

I don't see Gomer much since he got out of the Marines. Actually, Gomer is my cousin thrice removed.. I'm a "Pile" and Gomer is a "Pyle"... ;)

RustyPile 01-04-2026 07:02 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by 1970 CST Short Wide (Post 9417070)
Thank You RustyPile. This is what I Love about this site. You present a problem and people respond, my bad for missing your post but Guess What, that was it. If I put on the brakes and then the turn signals right after they cancel the left brake light stops working. Turn the signal back on and you get brake light. If you just turn off the signal without turning the wheel the brake light works. Definitely will replace turn signal switch but also thinking New column as this is an Auto Tilt Column and I now have a Manual trans

Once again thank you and everyone else that gave input.

Anybody have suggestions on a Manual Tilt Column

As others have said, some of the aftermarket tilt columns are hit and miss.. When I have need for a Manual Tilt Column, I search for either a pre 90s Camaro or Malibu column.. FWD and later columns always turn out to be too short and/or bulky...

1970 CST Short Wide 01-04-2026 08:10 PM

Re: Brake light gremlin is back
 
2 Attachment(s)
Decided to keep the column I have now as it’s an original 72. When I rewired my truck I don’t know why but I never even thought about the Turn Signal Switch,Go Figure.
I Removed the signal switch, ya it needed replaced.

MikeB 01-05-2026 01:28 PM

Re: Brake light gremlin is back
 
Quote:

Originally Posted by 1970 CST Short Wide (Post 9417286)
I Removed the signal switch, ya it needed replaced.

That's one nasty switch!

I suggest using an AC Delco replacement. I've been 100% satisfied with them, wherever they are made. Typically it's in a GM facility in Mexico.

pjmoreland 01-05-2026 08:45 PM

Re: Brake light gremlin is back
 
The original switch in my K/10 looked like that. I cleaned the contacts with Scotchbrite, lubricated it, and reinstalled it. It's working great. I have had issues with reproduction switches. One had an issue where the horn contact spring clip stuck out and created a short, which caused the horn to be on permanently. Another had an issue where it did a poor job of canceling the turn signal in one direction.


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