Electical Problem

I have 2003 Expedition, i love my suv but i have some problems , my heated and cooled seats do not work , day, night headlights do nor work, the radio works but it must be shut off manully, the voice on the navigation does not work, keyless entery does not work,the chime does not work when the door is opened. i know it sounds like alot but it does not burn oil , no knocking, does not leak oil, starts up no problen weather it is 90 degrees or weather it is 10 below outside.it has 175,000 miles on it 5.4 4x4 leather and it is loaded, if it takes 1,000 to fix thats better than spendind 35,000 on a new one. i am disabled and i am an a fixed income ssd .if someone could help that would be great , thanks matt from Michigan.

The help anyone can give by internet will be fairly minimal. You have a wiring problem or three and someone has to find them. This requires good wiring diagrams a decent volt meter and basic knowledge of electrical circuitry. It also often involves some interior trim disassembly. If you have any aftermarket add ons installed (anything that requires wiring work to install it) that area is the place to start.

At the moment you can at least check the fuses. If you find any blown then some things may temporarily work again with a new fuse. But normally a fuse blows because of a circuit problem, so you’d still need to find the problem/s.

What you need is a local, independent repair shop that has someone who specializes in electrical troubleshooting.

I’m not an automotive electrical system expert, but it sounds like a wiring harness problem. Michigan salts the roads during the winter and over the years salt will corrode wire, connectors and fuse boxes. Get a specialist to give you a service quote. The difficulty in getting a fixed quote, is solving the problem takes time and they won’t know how long it will take before getting started. Rather than drop $1k on fixing an eight year old car with 175k miles, I’d put the money toward another 4 - 5 year old used vehicle and get whatever I can for this one.

Has Michigan salt caused corrosion to electrical connections?
First, I would check all fuses.

Remove NEGATIVE battery cable - if you touch any part of the car with the metal wrench, there will be no short.

Are there any salt-exposed plug connections which you can access and pull apart and, if corroded, FLUSH out with forceful water spray? Then thoroughly dry and plug together than take apart and dry again? Repeat until clean andry.

Interesting that the radio does not turn off.
Is a relay sticking from getting enough leaked current or backfed currenthat it acts as though the ignition is still on?
Best to see a circuit schematic. Often I have been able to diagnose and repair problems just from symptoms and seeing a schematic.

I would pull each relay one at a time, clean its plug contacts and knock it in case its points are sticking. I would test the relays with a volt/ohmeter to discern if contacts which should be open are making contact. If so, take the case off and see what is wrong.
I have fixed sticking relays.

Change the negative battery cable and clean up the engine to body ground. Abandon vehicle.