Hi, I am a professional certified mechanic, with an engineering background, and 35+ years experience. I will do my best to assist you. Also keep in mind I don't know if you are a pro or a novice, so feel free to add any additional info at any time.
Have you had the wires to the sending units on the engine checked to see if they are plunged in like they should be. If they were disconnected, and not properly reconnected it could cause the exact problem you are having. If the wiring harness was pulled on it might cause continuity problems that could shut the gauges down. Sometimes if you work on the wiring, you can cause unintended problems by moving other wiring around while you are working. A wire can break, or an electrical plug can accidentally get disconnected. I would have these things checked. I know it is a lot of wires, and if possible it would be a good idea to get the person that replaced the bad wires to check it out. No one but him knows better where he moves wires around, this will give him a good idea of where to start. Go over all of this and if you have any more questions at all, I am here to help. Good luck with it, have a great day, and Thanks for using Just Answer.
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