Both circuits have the ignition switch in common. If wiggling the switch gets things going, the contacts inside it are arced or pitted. If that doesn't work, inspect the connector terminals for signs of overheating. If you find that, about 4" of two wires will also be hardened, and solder won't adhere to them. Replace the switch if you find that, cut those two terminals out of the melted connector body, cut off the hardened part of the wires, splice in new wires, and use new crimp-on terminals that you can plug in individually, but solder them too.
This happens most commonly when people use the heater fan on the highest speeds a lot. The very high current is hard on the switch contacts.
Read the guide below on using a test light, its the best way to check for power
https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester
Attached below are all of the power distribution wiring diagrams for your truck
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Monday, December 30th, 2013 AT 1:51 PM