Dash lights not working

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Kowboy

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I’ve had this issue for a while and now it’s bugging me, I know what the cause is but don’t know how to fix it. I put a RetroSound radio in my truck a few months ago and since then I haven’t had dash lights, I know its back feeding power and blowing the fuse, I just pulled the fuse out for my dash lights so I don’t keep blowing the fuse. Now the RetroSound radio requires constant power and keyed power, but only has one power wire in its harness. My question is what’s the best way to correct this so I have dash lights but still have my radio
 

mtbadbob

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Disconnect the radio & then see if your dash lights work.
 

mtbadbob

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The constant power is for memory, but you need to run the radio power to radio fuse directly, to the non-hot side. This should not back feed any other circuit and should burn the radio fuse first if there is an issue.
 

Kowboy

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The constant power is for memory, but you need to run the radio power to radio fuse directly, to the non-hot side. This should not back feed any other circuit and should burn the radio fuse first if there is an issue.
Which wire is that, cause I have 2 gray and one black, I know one gray is constant power and I believe the other is keyed and also is the wire for the old light but since I no longer have that and since both are tied together I think that’s what’s causing my issue, so should I take the keyed gray out and replace it with the black one? This is also in a 74 K10
 

RustyPile

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I’ve had this issue for a while and now it’s bugging me, I know what the cause is but don’t know how to fix it. I put a RetroSound radio in my truck a few months ago and since then I haven’t had dash lights, I know its back feeding power and blowing the fuse, I just pulled the fuse out for my dash lights so I don’t keep blowing the fuse. Now the RetroSound radio requires constant power and keyed power, but only has one power wire in its harness. My question is what’s the best way to correct this so I have dash lights but still have my radio
The dash light fuse isn't blowing because of "back feed".. It's blowing because it's wiring is not heavy enough to carry the current of the lights AND a radio.. There is a receptacle on the fuse box marked "Radio". That's where your radio can receive key on power. The constant power needed for the radio can be had on the cigarette lighter plug or courtesy light plug or the dome light plug. Stop guessing at which wires on the radio do what.. This information should be in the installation instructions.
 

mtbadbob

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Are you talking about the factory radio wire colors? Are you using the factory radio plug with an adapter harness, or does the Retro Sound have the same type of plug socket so the factory harness can plug into it? Aftermarket grey wires are usually speaker colors.
 

Jgonick

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Truck yellow changes to retro red- switched power.

Truck orange to retro yellow (with fuse) is batt- always on. (Most people splice to orange wire going to cigarette lighter.


Truck grey is not used- it is for back illumination that retro doesn’t have

Black is ground.
 

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Kowboy

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The dash light fuse isn't blowing because of "back feed".. It's blowing because it's wiring is not heavy enough to carry the current of the lights AND a radio.. There is a receptacle on the fuse box marked "Radio". That's where your radio can receive key on power. The constant power needed for the radio can be had on the cigarette lighter plug or courtesy light plug or the dome light plug. Stop guessing at which wires on the radio do what.. This information should be in the installation instructions.
There was no information in the instructions I was disappointed in the quality of that, I have my CB using the cigarette lighter wire since the truck didn’t have a cigarette lighter to begin with, I will definitely tear my dash out today and fix this
 

Kowboy

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350
Truck yellow changes to retro red- switched power.

Truck orange to retro yellow (with fuse) is batt- always on. (Most people splice to orange wire going to cigarette lighter.


Truck grey is not used- it is for back illumination that retro doesn’t have

Black is ground.
I have 2 gray wires coming from the truck harness and one black I didn’t use, I used the cigarette lighter power for my CB power wire I don’t think I have an orange wire in the truck harness
 

Kowboy

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Are you talking about the factory radio wire colors? Are you using the factory radio plug with an adapter harness, or does the Retro Sound have the same type of plug socket so the factory harness can plug into it? Aftermarket grey wires are usually speaker colors.
Yes factory harness the RetroSound doesn’t have a plug so I had to cut the factory plug off and use a junction block to wire it up
 

Jgonick

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2 gray wires- look at the diagram in post #7. If you cut the connector off (or someone else did) I would guess one gray wire continued on to the lamp. GY=gray. Y=yellow B=black

Example of reading diagram
18 GY -150C
(Wire size) (Color) (-Circuit)

I’m not 100% sure, but fairly certain you can still splice into the cigarette wire- the radio shouldn’t draw a lot of amps just to keep memory.

Retro black ought to be connected to truck black - ground.
 
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Scott91370

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FYI, if you do not have dash lights you more than likely do not have taillights.
 

mtbadbob

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Yes factory harness the RetroSound doesn’t have a plug so I had to cut the factory plug off and use a junction block to wire it up
They make kits so you never have to cut/alter a factory harness, all your splicing occurs on the radio side of the plug. It's way better than Okie-rigging your factory wiring, you're just asking for trouble.
 

RustyPile

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I have 2 gray wires coming from the truck harness and one black I didn’t use, I used the cigarette lighter power for my CB power wire I don’t think I have an orange wire in the truck harness
Look again, yes you do have an orange wire.. As I stated -- it is always hot.. It carries power to the dome light, courtesy lights if you have them, and among other items -- power to the horn relay and cigarette lighter.. Question.... Do you have a wiring diagram for your truck and are you using it for reference?? I have a wiring diagram in front of me, the orange wire is definitely illustrated..
 

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