Electrical Tail lights on but dim

[Deleted member 215073]

I recently converted the tail lights on my 1993 GT to LX style and used all LED bulbs. Now I have noticed that the tail lights are on but dim with only the ignition on. Even the 3rd brake light is on and dim. When the lights are turned on by either depressing the brake pedal or turning the clearance lights on they work normally.

The front clearance lights remain off when the lights aren't on.

I replaced the headlight switch and it didn't fix the problem. I'm thinking I may have a bad ground in the rear.

Thoughts?

Dim glow

Brake pedal depressed

Clearance lights on

 

[Kid wita 5oh]

Im having the same issue. All new leds and they glow dim when the key is on.

Did you ever figure this out?

I was thinking a ground issue or possibly a multifunction switch. I was looking for a wiring diagram but Mitchell's ProDemand only has a few random diagrams for these

Anyone have a tail light wiring diagram?

 

[Kid wita 5oh]

Got a chance to take a look at it today. Got it figured out pretty quickly...had 5v on the brake light circuit with key on.

Unplugged brake light switch, lights stayed on.

Unplugged gray body harness connector behind drivers kick pannel and lights went out.

Disconnected battery and started checking for shorts...found the brake light wire had continuity( In the 6.5k-9k ohm range) to most of the other wires in the gray plug. The brake light wire was perfect from gray plug to brake light switch( 0.03ohm)

No signs of melted or chewed wires in the harness... Followed the wire to what I found out to be the cruise control amplifier (thanks to @Mustang5L5 cruise control thread) unplugged it and connected the battery. No more stray voltage on the circuit. Just leaving it unplugged until I can get a new one.

Wanted to share the find in case anyone else has the problem

 

[General karthief]

Is the amplifier year specific?

 

[Kid wita 5oh]

Seem to be year ranges. Up to 88, the 89-93

Foxbody Cruise Control information, location, wiring diagrams

Done a little research into this and figured what I learned should be put into a thread and added to the tech sticky. As you can imagine, nobody really gives much thought to cruise control on these cars, so many searched threads had dead ends. So many this will help someone out down the road...

stangnet.com

 

[General karthief]

@Kid wita 5oh PM me