This morning I went to start my 85 Suburban and all sounded good very briefly then nothing. I have dual batteries fully charged in 6.2 diesel, i turned the ignition on heard the buzzing waited glow plugs lit up then I turned it over. The starter turned the motor for a single rotation then nothing. I turn the key off and on and nothing. The buzzer does not work it basically seems like I disconnected both batteries and not even the headlights work.
My car has 51000 miles.
My car has an automatic transmission.
This sounds like quite likely a grounding problem. I would recommend starting by checking the positive battery cables looking for corrosion on the connectors and cables.
Next, I would check the fuses for power. Try checking one for the headlights to see if they have power. Sometimes what is called a fusible link can burn up causing a ground problem.
Also check the rear trailer plugs (if applicable) to see if they have any exposed wires or corrosion as they have a tendency to have the insulation worn off which can also cause a short.
Check the ignition switch for bad wires, connections, or burnt wires. As you may know, tracing electrical shorts can be very tedious and time consuming. I would recommend having an expert from YourMechanic come to your home to diagnose the electrical issue and help you repair it as necessary.
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