Lennox MPB012S4S

104
Error Code: E2 (continued)
UseamultimetertotesttheDCvoltagebetween2portand
3portof outdoorunit.Theredpinofmultimeterconnects
with2portwhiletheblackpinisfor3port.
Whenunitisnormalrunning,thevoltagewillmovealternately
betweenpositivevalueandnegativevalue.
Self-Check OK
Power (some
modles)
Opera ng
Power(some
models)
IPM(for2-zone/3-zone)
MainboardLEDwhenpoweronandunit
standby.