Brake light puzzle

[Kowal]

'69 GTX.

Passenger side brake light isn't working, nor the same light for the hazard lights. The regular lights and turn signal are working on that corner. Need ideas as to what it could be. So far I have:

Tried all kinds of combos of brass and tin bulbs. No impact
Jumped the socket with a separate ground wire, no impact
Made sure all connections are clean, checked ground. No difference
No obvious damage to the harness in the trunk.

 

[bm02tj]

turn signal mech in steering column

 

[Tori]

First off, you need to see if you have 12v + signal at the socket. Then start at the switch and follow the flow till you find the problem.

 

[Nacho-RT74]

I have to recheck how does work the hazzard/brakes system on pre 70 cars. Is a bit more complex than post 70 running these throught the divorced hazzard switch. Will refresh my memory checking the diagrams later.

 

[Glenwood]

I have to recheck how does work the hazzard/brakes system on pre 70 cars. Is a bit more complex than post 70 running these throught the divorced hazzard switch. Will refresh my memory checking the diagrams later.

my 64 hazard basically has a pullout switch that splices into the steering column wiring and channels the four lights through a flasher.

 

[Nacho-RT74]

Yeap, is like that up to 69. Althought can't tell the first ones where as far I know hazzards were somekind of optional and not standard?

 

[Nacho-RT74]

Ok here I go.

I see one red, one white, tan and light green wires at hazzard switch.

Tan and light green are the source to front blinkers.

White Brake lights we is spliced into the hazzard switch just to feed the rear lights throught the turning switch ( dark green and brown ) when red wire coming from flasher is activated turning on the switch.

So, when you turn on hazzards, red wire ( emergency flasher ) feeds both front blinkers individually, and both rear blinkers together in just one wire throught the brake light system up to turning switch where its spliced To both sides, dark green and brown. This saves built a larger hazzard switch with an extra prong and extra inner contacts assembly.

If you are getting one side of hazzard/brakes on rear in working order the main sources are good and the problem is the "splice" built into the switch for rear lights which is not feeding the other side. Somehow some point or track inside the turning switch is not making contact with the splice to the right rear side when switch is in rest position, but making contact when right side turning is activated.

This makes me to think time to rebuilt or replace the turning switch. There is a chance just replacing the cam switch piece ( available ) could be the solution

 

[Kowal]

Great ideas. I will take a look this week, good thoughts as to where to start

 

[Kowal]

Great ideas. I will take a look this week, good thoughts as to where to start

Well that was quick. No key in the ignition, foot on the brake, wobble the turn signal lever and I can get one or both lights working. So, guess I know what project I have to do next! Thx

 

[Nacho-RT74]

Ok it seem definitelly the turning signal cam replacement could make the trick. Replacements are out there without need for a full switch replacement

 

[Kowal]

Ok it seem definitelly the turning signal cam replacement could make the trick. Replacements are out there without need for a full switch replacement

Just finishing up the string. Replaced the turn signal switch and harness with a NOS one, had heard and seen on websites too much info on failed reproduction units and didn't want to do this twice. Anyway, worked perfectly. All lights work as should. Sort of remarkable really.