55.2-59 58 Apache wiring

[RostaRob]

I'm back with a few more questions regarding the rear indicators. I've attached a drawing of what I have and was hoping someone could chime in with what they have wired. So I have 3 wires coming from the cab/dash-Green, Yellow and Red/(brown from fading?). Drivers side indicator has two wires-Blue and Green, Passenger side has two wires-Blue and Red. I have hooked both Blue wires to the Red/Brown wire, passenger side Red wire to cab Yellow wire, drivers side Green wire to the cab Green wire. Here's my dilemma-turn signals work, brake lights work however with brake pushed and brake lights illuminated my turn signals flash very dim. Have I got everything wired up right? Would a different (LED) light make a difference with the turn signal visibility? Do they make bulbs that would just plop in or would I have to buy a different indicator. Thanks for any help. Rob.

One additional thing...right turn signal indicator on dash doesn't illuminate when signal or s on but comes on and stays on if I turn on the headlights. ????

[_Ogre]

all of your problems appear to be grounding issues
dim turn lights and backfeeding from headlights are grounding issues

[RostaRob]

Thanks. I'll recheck all my grounds.

[dsraven]

run a ground cable to the frame and engine. normal gauged battery cable.
run a ground wire to the cab, rad support and box from the frame
clean all the metal surfaces down to bare steel, use star washers under the screw head, then seal with liquid electrical tape or paint or whatever

or

run the larger ground cables like above
run separate ground wires from each light to the frame to eliminate the body as a ground. the front lights are sitting in the fenders but normally ground on the rad support. the rad support sits on rubber bushings so it relies on the bodywork attached to it to supply enough ground conductivity for all the front end electrical. this would mean the battery would need to ground to the frame so the cab, sitting on the frame at the front mounts, could supply a ground through the fenders which bolt on to the cab and on and on. the foot bone is connected to the leg bone kinda deal. if you run a dedicated ground to the rad support you eliminate all those other "kinda sorta" connections which can get better or worse depending on the weather, how much the truck has rattled down the road, the rust on the fasteners etc. better off to make a positive ground and not rely on all those other joints.
when light has a bad ground the current will go through the bulb element like normal and try to ground on the bulb socket like normal. if no ground at the socket then it back feeds through the other circuit (in a dual filament bulb) which is also sharing the socket ground, and will find a ground in that other circuit somewhere. it could be the dash bulb ground or maybe go all the way to the tail lights to ground. that is why the indicator light will not come on with the signals but when the headlights are turned on it comes on solid. the headlights are finding a ground by backfeeding through the common ground of the rad support and from there through the signal circuit to ground at the dash bulb.

[dsraven]

lots of guys around here (the great white north, eh) use flexible all weather extension cord style wiring (sourced at home depot) for the run from cab to tail, if you get the 4 wire stuff the extra wire can be used for a back up light. you can also run a waterproof terminal box at the rear and some compression fittings on the cord that way to keep the weather out of the connections. it's out of sight under the truck and looks neat and tidy anyway. better than twisted connections with some ratty old electrical tape over the joints and cable ties along the frame. up to you though.

-tail light wire-common to both sides
-turn signal and brake wire-separate wire for each side. don't connect the front and the rear turn signals together or you will also have brake lights on the front (seen it done before)
-ground wire from light socket to frame-mandatory (in my world) as well as ensure the light has a good ground path through the unit. some have flimsy mounts from the actual light bulb socket to the light housing so it creates a poor connection
-double wall shrink tube over all joints-mandatory (in my world) as well as a good set of crimping pliers. give the crimps a good tug after each crimp to ensure they stay together. try to use a heat gun instead of an open flame on the shrink tube because open flame sometimes gets the tube too hot and it cracks or gets hard when it cools off.
-grommets where the wiring goes through sheet metal-mandatory (in my world) to eliminate future issues.
-wiring clamps to support harness-mandatory (in my world) to keep stress off the connections and also protect the harness from mechanical damage.
-a little corrosion inhibitor on the bulb in the socket- mandatory (in my world) to keep the system running like it should and not allow corrosion on the bulb terminals or the socket.