instrument cluster voltage limiter

The early bi-metal type gauges were sensitive to voltage fluctuations. If the alternator was putting out 14v and you turned on lights/heater/wipers and the voltage dropped to 12v, the gauge would read differently. The IVR put out a constant 5v and the gauges were calibrated to 5v, so they would be unaffected by system voltage changes. The new air core type gauges have two opposing coils and are not affected by system voltage fluctuations, so there is no need for an IVR