My son has an 82 F150 4X4, it all of a sudden is completely dead electrically. It will not crank, will not power anything with the key in accessory. There is 12.7V at the battery, it seems normal. This happened suddenly for no apparent reason. Any suggestions where to start troubleshooting?

 

Welcome to FTE.

Take a look at the wiring over at the battery, look at the condition & functionality of all the heavy cables over there, their connections to the starter motor & engine block, too. This problem could very well be a crappy battery connection, a blown fusible link, a defective battery, something else.

Might try jumping the solenoid and see if the starter motor can be triggered to operate.

 

Thank you, do you know where the fusible link is on this truck?

 

It/they are all attached at the battery + side of the starter relay, near the battery.

 

Details of how to do that are in post #15 in this recent thread:

https://www.ford-trucks.com/forums/1...l#post18145762

That's a good quick test to start troubleshooting. Report back with the results and we can help you decide how to proceed.

Also, scroll up to post #8 in that same thread. Do you have those type of battery terminals?