mooney2201 Posted July 25, 2025 Report Posted July 25, 2025 (edited) My highlow volt annunciator came on after I washed the plane...but all systems are showing 14volt charging.. Where does the annunciator get its signal from...alternator is working fine. Its 1978 m20j Edited July 25, 2025 by mooney2201
rklems Posted July 25, 2025 Report Posted July 25, 2025 Note: this is assuming factory connections, your M20J looks pretty upgraded, so there is always a chance something was modified on how they are connected. There are 2 signals... the low voltage is sensed from the power input to the entire annunciator, pin 1 at the annunciator connector (21WT02C22), which is powered from the 2A annunciator breaker (after passing through the CPC at the back of the breaker panel). The high voltage signal is pin 11 (21WA02D22) which gets its signal from the voltage regulator (also after passing through the CPC at the back of breaker panel). You can pull the connector off the back of the annunciator panel and check what you have on both of those pins. Also, this is referenced to the ground at pin 15 (21WT03C22). 1
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