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2007 Chevrolet Cobalt (Wiring or Ground Issues)?!

I have a 2007 chevrolet cobalt, The other day i was sitting in my car with it started for a few minutes, everything was operating fine and drove it all morning prior to this, I went to go put it in drive, shifted into Drive just fine and it acted like it was going to go as I pressed the gas and all of a sudden just died. When i put it back into park and attempted to start the car I heard repetitive clicking but only when i turn the key to accessory, upon further inspection, here i am stuck and i notice other things, The Fuel Pump will no longer engage, I get a clicking noise only when in ACC mode (guages jump and weird warning lights come on) and absolutely no sign of starting or turning over when i turn the key to start it… Also Im stuck in Park, my car will not shift into Neutral or Drive! We have inspected the battery, relays, some fuses, tested just about everything except the fuses underneath where the passenger side is and the wiring, HAS ANYONE ever had a similar issue because I need to be pointed in the right direction I dont know what else to do… it was Running, Shifting, Starting and Idling just fine all prior to this and now i am stuck on what it could be…

The battery measures 12.4 volts or greater with the ignition on? Remove and inspect the battery cable connections.

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yes, it read 12.63 V

Check the voltage getting to the fuses in the panel under the hood while the ignition is on. The battery cable connections may have a corrosion problem. Clean the battery connections to see if that helps.

did that, we just hooked up to computer, said theyre is a power and communication issue with the Transmission Control Module and or Wiring Issue that goes to the computer, TCM is in front of fuse box underneath the hood…

There is a greater power problem than to just the ECU and TCM. The trouble is most likely between the battery connections and the main distribution panel under the hood. The trouble could be due to internal wire corrosion, which is usually at the battery connections due to acid leaching into the wire. The problem is most likely on the hot side of the wiring but it could be on the ground side also. Looking for a voltage drop across the wiring while under load should locate the trouble fairly quickly.