Author Topic: LED Third brake light for my 1984 Chevy Stepside  (Read 1379 times)

Offline Chuck Step-a-side

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LED Third brake light for my 1984 Chevy Stepside
« on: June 03, 2018, 10:04:13 AM »
I have just installed a LED Third Brake Light below the tailgate and tapped into the lt. green wire for the brake light signal. The Third Brake Light will come on with the parking lights or/and the brakes. Anyone know what can be done to get the Third Brake light to work with the only the brake signal? Thank you.

Offline bd

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Re: LED Third brake light for my 1984 Chevy Stepside
« Reply #1 on: June 03, 2018, 11:21:32 AM »
To eliminate circuit backfeeding you will need to establish perfect ground connections to the rear lamps.  But, there is a problem with your wiring logic, too.

Light green is backup (reverse), dark green is right turn/brake, yellow is left turn/brake, brown is tail/park/license plate, black is ground.  Unless the third brake lamp contains a logic circuit, it will need to draw power from a dedicated brake lamp wire that connects directly to the brake switch, bypassing the factory turn signal switch and rear lamp wiring.  Otherwise, it will flash with the corresponding turn lamp.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Chuck Step-a-side

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Re: LED Third brake light for my 1984 Chevy Stepside
« Reply #2 on: June 03, 2018, 12:15:11 PM »
Yes, I was looking at the wiring diagram and saw that I can piggy off the white wire at the brake switch and then run a wire to the + on the third light. Thanks.