Radio has no power

[Sam7.3]

just bought a 94 explorer that had no radio. I went to install one and it was getting no power. tested the battery, fuse in the engine bay and all check out. checked the fuse panel under the dash and the fuse gets power, but when I test the green/yellow wiring (constant 12v power for radio) there is no power. PLEASE HELP! I'm about ready to blow my mind out from driving with no music

 

[timtimtimajim]

Are you getting power through the switched wire for the radio? It's yellow/black. The constant power wire only provides power so that the radio can retain memory. I know you said it you checked the fuses, but it wouldn't hurt to throw a new fuse in and see what happens. Could also be an issue with the wire somewhere underneath the dash.

 

[92exp4x4]

I have had fuses check good with a test light and still be bad. One that burned me had power on both points when installed. I checked it multiple times. Then I finally pulled it and the spade terminal on the load side of the fuse had broke off. It stayed in the holder.

I will never know how a fuse could fail that way. I spent a day working on that one.. I had nearly the whole harness out of a Kalmar 55,000 lb capacity forklift trying to figure that one out!

 

[larrydd999]

Vibration. I've had it happen on our boat (and there are no longer any miniature or sub-miniature blade-type fuses on it). The small blade-type fuses are prone to that type of failure because the fuse wire is stronger than the connection to the blade and the plastic is not very strong either. Sometimes the blade breaks off, sometimes the fuse wire separates from the blade.

 

[92exp4x4]

Makes sense. It drove me nuts!

 

[Sam7.3]

I have had fuses check good with a test light and still be bad. One that burned me had power on both points when installed. I checked it multiple times. Then I finally pulled it and the spade terminal on the load side of the fuse had broke off. It stayed in the holder.

I will never know how a fuse could fail that way. I spent a day working on that one.. I had nearly the whole harness out of a Kalmar 55,000 lb capacity forklift trying to figure that one out!

thank you i checked the fuse and was blown, i also figured out (from driving with no radio i had to think of something to pass my time) that there was no power going to the factory amp, wired the 12v ignition straight to the factory amp power wire and now i can enjoy a ride with music

 

[92exp4x4]

Awesome, glad to help.

 

[malohnes]

Awesome...simple fixes are the best. Sometimes its the work to determine the simple fix thats hard!

 

[larrydd999]

Be sure to install a fuse in the ignition circuit you ran to the amplifier. While occasionally troublesome, fuses do protect wiring and the sometimes undersized (i.e. SAE rated) wires in a vehicle really need to be protected. Solid-state electronic devices often fail shorted and without a fuse (or circuit breaker) will quickly get a wire hot enough to start a fire.