Basically, inaccurate readings. Fuel can show 1/2 tank when it's empty, or just not move much off the peg at all, that kind of thing. Change out the gauge & no improvement, so a guy figures it's the tank sender. Change that and no improvement! $100+ later he/she changes the regulator and all's well and they have some expensive spare parts.

I've heard of various temp gauge problems also. I'm not sure what gauges are using the 5VDC on all the different Mopars so I suppose it might effect other gauges, don't know.

I really don't know why they added the resistance factor, to lower voltage to 5VDC, other than the 5VDC voltage regulator can prevent perfect direct readings. That means that otherwise the temp gauge would fluctuate every time thermostat opens/closes or fuel gauge would swing around the dial every time you hit a bump with a partial tank full. The 5VDC regulation acts as a buffer or delay mechanism to slow readings, making life more enjoyable in the cockpit, if the regulator works!

The solid state upgrade offers the same resistance factor to slow readings I guess.

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