Another rear light question

Hi all- working on the rear lights of a 57. When I wired up the right side- it seems the brake filament is lighting rather than the dim one for parking light -on right side only. left side is fine- turn signals fine on both sides too. Is there an easy reason for this or do I need to get back in there with the test light.
Thx!

 

Perhaps a bad ground which causes current to back-feed through the wrong filament.

 

Sounds like you have the two filament wires swapped. Needs more tinkering.

 

Yes but he said the turn signal is fine.

 

Hmmm, complications.....

 

X2- that is what was wrong with mine....

 

R u working with original fixtures or after market? I had same issue but with aftermarket fixtures. The 1157 bulbs were not seating correctly in the socket. After a whole day trying to figure out what was up I took off the lenses to check the bulbs. Removed them and then reinserted until I heard an audible click for both the top and bottom contacts. Sure enough that was the issue.

 

Thanks- I'm not sure. At this point- I can't tell whats original and what's not. Lol But did make progress. I now have signals working and parking lights working on both sides. Left side brake light works but only thing not working is the right side brake light.
Heres my logic- three wires from main harness- two are signals (all working) and the other last one is for parking/brakes. Left side is fine and I spliced it and ran a new wire to black wire of right side. (Reds are all directionals going into light). So either right side bulb is messed or contacts mentioned above by Bill67. What else could it be?
btw- it did run today after a new coil! So we are getting close.

 

take a look-see at the connection on the brake sw,be sure theirs a good clean connection their,the brake light sw gets its power from a different soarse than the signal light.

 

"and the other last one is for parking/brakes."

Errr...no. Brake light and parking light are two different circuits.

Brake and turn both use the same "bright" filament in the bulb and can share a wire. Parking are the "dim" filaments, need their own separate wire.

But the parking circuit can be one wire that feeds both left and right sides. Turn/brake circuit needs two wires, one left, one right.

Sketch it out on a piece of paper and it will make sense.

If your wiring and bulbs are correct then the issue may be in the turn signal switch, which is where the brake and turn functions are differentiated.

 

Shoot- you know, I didn't even think it could work that way. I figured my test light was "always on" when the parking lights were on- it had to be the same wire that some how magically boosted the power to make it brighter for brakes. Kind of makes sense to me. lol. It's an easy swap when I get home. Thanks so much!

 

After more test light poking- it seems it could be the turn signal switch.
3 wires in the back and
Wire #1- left light has left directional AND stop
wire #2- right light has right directional signal NO stop
wire #3- parking lights- fine
so I think wire #2 is not getting stop signal from the turn switch.

 

Use test light to see if you are getting stop power out of the turn signal switch to the phenolic (bakalite?) plug-in for the right stop circuit. May have bad connection at this plug assy. If no power out of T-sig switch then it's time to repair switch.

 

The switch can be dismantled and cleaned up if you are careful... very careful!

 

Issue at hand is no right brake light.
I took the turn signal apart, it looked pretty clean inside. 7 wire Signalstat 900. Here is the layout:
0. ->Yellow (Not worrying about this one)
00 00. -> Gray green(left). Red black(right)
0. ->. Gray w black stripe ( not worrying about this one)
1-only brakes on- outside gray and black contacts light up ( this is good I think but right brake light not lighting up)
2-only parking lights on- green only contact on ( this must be ok since all parking lights are working)
3-brakes on with left turn signal on- gray, green, yellow flash And black constant on. ( right brake light not lighting up)
4-brakes on with right turn signal on- black, red yellow flash And gray on constant (this all works in the back - right directional flashing and left brake on so must be fine)

So I think the Ol Signalstat is working OK. When I look at the wiring diagram- it goes from Signalstat straight to the back lights. Got to be a bad black wire to that back right light. Yes?

 

Yes

 

Success! New wire did the trick. Thanks for the help!

 

Glad you got it.