I have a manual 2007 Mustang 4.0L and when I accelerate the A/C and Dashboard electronics, gauges shutdown. I was wondering what the problem is, there is a 24pin connector that is hanging down on the passenger side but I can’t find out where it goes. Any ideas?

 

First guess would be the Smart Junction Box has gotten wet and corroded. Known issue with these cars. It's also possible the box just went bad on its own.

Other items to look for are SJB connectors, battery terminals, bad battery, bad alternator, other wiring issues.

You might need a dealership or really really good mechanic to sort this one out.

Maybe someone else will chime in, but thems my thoughts.

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