I installed an E-Mag as the left mag in my RV-10 with an IO-540 engine. The all Garmin panel includes two Garmin G3X units with the Garmin GEA 24 Engine Indication(EIS) System. The right mag is a Bendix mag. The newly installed E-Mag appers to function as expected except for the engine RPM displayed on the EIS. The EIS shows an RPM of Zero when the engine is running. The EIS is calibrated as specified for “Electronic Ignition (3 pulses/rev).” The EIS functioned correctly when the UMA Magnetic Tach Sender was installed on the left Bendix mag, which was replaced wih the E-Mag. To determine if the EMag was generating and sending three voltage pulses per revolution to the EIS, a voltmeter set on AC was used to check for voltage pulses per revolution while pulling the prop through by hand. The E-Mag was tested with the voltmeter grounded first to the airframe and then to the engine. In both instances the voltmeter showed three voltage pulses per revolution with the voltmeter connected to the blue wire from the E-Mag and the Garmin EIS no longer connected to the blue wire. The pulses varied in voltage, but the transient voltage readings were mostly in the 5 - 7 volt range. Any suggestions for resolving this issue?