Ford Ranger Electrical Problem

My 1999 Ford Ranger XLT, 6 cylinder, auto trans, with 134K miles has an electric problem. When I turn the key to the ‘on’ position, all dash lights show normal, headlights work, radio plays, etc. But when I turn the key to the ‘start’ position, all electric power is lost. The power remains lost until I disconnect and reconnect the battery ground wire. After reconnecting, I again have power until the key is turned to the ‘start’ position. I was able to jump start the truck, so I assumed I needed a new battery. I bought one a week ago, and was back to normal until today. The truck started, I drove 4 miles to the grocery store, and then I found myself back to square 1 (i.e., the no-start situation). Any suggestions appreciated.

I would start by checking all the ground connections. Check both ends of the ground cable and also look for the engine to chassis ground strap and clean both of those connections. If you have a small wire from the negative terminal to the body, make sure that the connection to the chassis is good and clean.

Is that a coded key? It might be the anti theft system, try a different key and see.

I’ve cleaned all the battery ground connections, and that seems to have been the problem. At least, I’ve started the truck several times today and it has started the way it’s supposed to. My first thought, too, was that the anti theft system was the problem. I’m glad it wasn’t. Many thanks for your suggestions.