• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Turn signals

Steven Tuttle

Member
Local time
2:03 PM
Joined
Mar 11, 2019
Messages
22
Reaction score
23
Location
New Jersey
hello all,
On my 72 roadrunner I replaced the turn signal switch all is great, but when I turn the lights on the left turn signal does not show up on dash and the rear brake and turn signal light is dim. Any suggestions. Possibly a short somewhere?
 
hello all,
On my 72 roadrunner I replaced the turn signal switch all is great, but when I turn the lights on the left turn signal does not show up on dash and the rear brake and turn signal light is dim. Any suggestions. Possibly a short somewhere?
Or a poor ground
 
Does your brake lamps both work when the turnsignal switch is off? If so could you have crossed wires when replacing turn signal switch?
 
Yes, the left rear brake light goes dim when the headlights are on. I’m confused on why it would do that. But again I did not wire it myself so it could be wrong.

When the headlights are on the left turn signal is very weak, and when they are off it works great.
 
Yes, the left rear brake light goes dim when the headlights are on. I’m confused on why it would do that. But again I did not wire it myself so it could be wrong.

When the headlights are on the left turn signal is very weak, and when they are off it works great.

If the left brake lamp dims when the head lamp come on I would look for a ground issue or corrosion issue in left rear socket or ground wire.
 
These signal lamps are so sensitive to grounding issues, my front left signal lamp was acting up until one day I replaced the metal screw. The old screw was too corroded to ground the lamp housing to the bumper. Some members on here advocate for running an extra ground wire directly to the socket.
 
Each side (right & left) has a black ground wire that is common to all lamps on their respective side. They are tied together somewhere up front. I don't know exactly where but look on your core support.
If you just activate your running lights (no headlights) do the turn signals/brake lights work properly?
 
Each side (right & left) has a black ground wire that is common to all lamps on their respective side. They are tied together somewhere up front. I don't know exactly where but look on your core support.
If you just activate your running lights (no headlights) do the turn signals/brake lights work properly?
I will check tomorrow and get back to you!
 
hello all,
On my 72 roadrunner I replaced the turn signal switch all is great, but when I turn the lights on the left turn signal does not show up on dash and the rear brake and turn signal light is dim. Any suggestions. Possibly a short somewhere?
Poor ground
 
These signal lamps are so sensitive to grounding issues, my front left signal lamp was acting up until one day I replaced the metal screw. The old screw was too corroded to ground the lamp housing to the bumper. Some members on here advocate for running an extra ground wire directly to the socket.
I know this is an old thread, do i need to ground the front turn signal housings ? Rear tail lights work, flashers work in the tail lamps, rear brake lights work, no turn signals front/rear front running lights don't work when i turn on headlights. I have the correct bulbs ( 1157) checked continuity on the column harness orange is hot, red is dead,light green is dead, red wire to flasher dead, black wire to flasher hot.
 
Have a wire with alligator clips foot or so long to create a quick ground check; I've verified a few grounding problems this way. As posted, checking for good ground is usually the first thing to look for.
 
Have a wire with alligator clips foot or so long to create a quick ground check; I've verified a few grounding problems this way. As posted, checking for good ground is usually the first thing to look for.
Thanks!
 
I use a test light grounded to battery with a long wire. Probe all the outside of sockets with lights on to find bad grounds. Ron H works to.
 
Auto Transport Service
Back
Top