I’ve got a 2002 ford f-250 7.3 L Lariet edition. It’s had an issue with the radio, windows and interior lights occasionally not coming on for the first few minutes after starting the truck. Within the past month it’s been getting worse: happens more often, not coming on for an entire drive.

I’ve realized I can smack the dash above the radio and sometimes get it all working again, so I was thinking it’s a loose connection, but I’ve been driving down the road and hear a “click” somewhere near my headlight switch and realize my radio/windows/interior can lights no longer work. Makes me thing it’s a relay.

Other oddities have been happening recently: the headlight and taillights wouldn’t turn off no matter what the switch position was or if the truck was running. I finally pulled the batteries and that fixed it.

Yesterday I put the key in the ignition and the horn started blaring non-stop. I didn’t crank the engine or even turn the starter to warm the plugs, just the put the tip of the key in and the horn went off. Same deal with that: I pulled the negative leads off the two batteries, put them back on, and no issues.

We haven’t had rain where I am in weeks, so I don’t think it’s a leak. Hoping someone here may have some insight.