SAAC Forum

The Cars => 1968 Shelby GT350/500/500KR => Topic started by: rsmith on August 18, 2021, 10:53:26 PM

Title: Taillight grounding
Post by: rsmith on August 18, 2021, 10:53:26 PM
Maybe I am missing something.......But since the taillight panel of the 68 is fiberglass, how are the taillight sockets grounded? I know there is a ground wire in each side's taillight wiring harness, but it appears to just screw into a hole in the fiberglass. How is the ground circuit completed between the socket and the ground wire? Can anyone shed light on this?
Title: Re: Taillight grounding
Post by: CharlesTurner on August 18, 2021, 11:23:03 PM
There's a tooth washer at the screw which helps with the ground.  Not ideal, but guess it's enough.  Problems with the lights is usually from the sockets coming loose.
Title: Re: Taillight grounding
Post by: Cobrask8 on August 19, 2021, 07:05:50 AM
This ground it CRITICAL for the taillights. Make sure that black harness goes from each lamp and body to that ground on the trunk panel (Gas and lock), and make sure that ground is PERFECT.

Otherwise, you'll be posting here all your taillight misery.
Title: Re: Taillight grounding
Post by: corbins on August 19, 2021, 08:26:13 AM
Ok.... so everyone may laugh at this , but I added  #14 wire  from the housing to the decklid bumper stop from underneath the nut that holds the bumper on. My lights look great and are bright. Closeout panel covers the wire anyway.
Title: Re: Taillight grounding
Post by: rsmith on August 19, 2021, 09:20:18 AM
Thanks for the input, but I still don't understand what completes the circuit between the taillight sockets and the ground wire screw. Is there a metal insert that has been molded into the fiberglass?
Title: Re: Taillight grounding
Post by: CharlesTurner on August 19, 2021, 10:04:04 AM
Thanks for the input, but I still don't understand what completes the circuit between the taillight sockets and the ground wire screw. Is there a metal insert that has been molded into the fiberglass?

The end of the screw is completing the ground into the housing.
Title: Re: Taillight grounding
Post by: rsmith on August 19, 2021, 10:17:02 AM
But the housing is non-conductive fiberglass, isn't it?
Title: Re: Taillight grounding
Post by: JWH on August 19, 2021, 10:32:21 AM
     I believe this is correct - the power enters the light bulb sockets, flows through the sockets to the metal tail light housings which are then grounded to the car’s body by the ground wire.

    The light sockets fit very snuggly into the metal tail light housings on each side. The metal tail light housings are grounded to the car’s body by the ground wire Charles refers too. I pulled out each light bulb socket from the metal housing and then using a fine Scotch Brite pad, cleaned the area of the metal tail light housing where the light socket makes contact. That made a big improvement in the brightness of the lights.
Jeff
Title: Re: Taillight grounding
Post by: TLea on August 23, 2021, 04:31:50 PM
But the housing is non-conductive fiberglass, isn't it?
Only if you have a repop panel with buckets molded in. Original tbird light housings are die cast
Title: Re: Taillight grounding
Post by: rsmith on August 28, 2021, 09:09:35 AM
Thanks everyone! I realize now (duh!) that the ground is thru the die casting!