i was driving down the road today and all of a sudden the truck just died on me, im talking now power what so ever no acessories no gauges at all. i first assumed the battery cable had come lose no such luch, i reccently replaced the alternator so i double checked the instalation and from what o can tell everything is all good there.

i have been doing some research and my next suspect will be the Shut off motor Rely. i just have to figure out which relaoy that is not sure exactly where to look.

any help would be great help, i will be getting a volt meter tomorrow to take a couple readings. not sure exactly what to do there as well.

what type of of truck is it?

Sry its a 1993 ram 150 with the 318.

A relay problem will not shut off all power. First check the main battery ground. Next start at the battery and check for voltage along the main wiring from the battery to the fuse block to find out where you lose battery voltage. There should be a bullet connector in the main battery power wire just behind the battery. This may be corroded or may have become disconnected.

i had same problem with my 93 d150 318. it may be the fuseble link to the ignition switch hot wire.
there is a molded connector on top of the driver side wheel well hump,it has 5 wires coming out of it going towards the cab.its the orange or red on the end of it closest to the engine,check it to see if it is soft mushy or feels broke inside. i cut mine out and replaced it with a inline 15amp maxi fuse. hope this helps, good luck

If he has no power at all and it is a fusible link problem then all of the fusible links would have to burn out at once. This is not likely. The problem almost has to be prior to the split off at the fusible links back to the battery or a no ground condition.

ok sorry, i should have explained my similar problem better,same thing happened but i had no power from key switch to anything that operated with the key,gauges,turn signals,starter,etc. just trying to help good luck