Started my truck today and it started for couple seconds then I went to turn my headlights on and it died. Now it won't turn over at all not even by gettin jumped got the battery load tested and it was fine. Also every now in the my aftermarket radio would turn on it off to I don't kno if this would cause this's also none of my lights come on inside or outside I put the key in and nothin happens except for a clicking sound like a relay clicking and my speedo is stuck over a hundred and no lights or gauges move when I turn the keys on and also I have to disconnect the battery cause the clicking sound continues even with the keys out ? Any ideas anyone what this could be ?

 

Welcome to the forum. Sounds like you have a bad ground somewhere. Check both ends of the main ground cable and all of the body grounds as well.