Lennox MPB036S4M

103
Error Code: E2
Description: Communicationmalfunctionbetweenoutdoorunitandallindoorunits.
General Note: Indoorunitdoesnotreceivethecommunicationfromoutdoorunitfor120secondsoroutdoorunitdoesnotreceivethe
communication from any one indoor unit for 180 seconds.
E2
Start:Poweroff,thenPowerontheoutdoorunitby
theBreaker.(reconnectthepowerwire).Isitstill
displayingtheerrorcode?
Checkwiringontheoutdoorandindoor
terminalsfollowthewiringdiagram.Areall
oftheconnectionscorrect?
Yes
Yes
Correctthewiring
No
Turnonallindoorunitsbytheremote
controller. Are all indoor units displaying
correctly?
No
Measure Vs, is it moving alternately
betweenpositivevalueandnegative
value?(Vsisthevoltagebetween3
and2).ReferPic1
No
A:Isallthewiringbetween
terminalsandindoorPCB
connectedcorrectly`?
No
No
Reconnectthewiring
Yes
ChangetheIndoorPCB
Yes
Poweronbyremotecontroller,itis
stilldisplayingtheerrorcodeafter
3minutes?
No
Yes
Turnoffalloftheindoorunits.Is
IPMpowerLEDoperatingLED
lampon?RefertoPic2.
Yes
Yes
ChangeIPM
No
Yes
Ismainboard”88”lampon?
ReferPic3.
No
Isthereactor
wiringproperly
connected?
No
Reconnectthe
wiring
Yes
ChangeOutdoorMainPCB
Yes
Aretheindoorunitsnumberedcorrectly?Check
ontheoutdoorcheckpoint.(2for2-zone,3for
3-zone,4for4-zone,5for5-zone).ReferPIC4.
Problem Solved
ChangeoutdoorunitPCBas-
semblytotally(includewiring).
Norsttime
No second time
A