I measured my (original) limiter with a device that records voltage to a laptop and I'm getting 6.2 volts about 25% of the time, otherwise zero. That gives me an equivalent voltage of 3V (square root of 0.25 x 6.2 squared). Not surprisingly, my gauges read low. I was thinking I might fix it just by bending the bimetallic strip to make it stay on more of the time, but if it's supposed to be passing 12V there must be some excess resistance somewhere.