Lennox Split & Multi-Split

Lennox Error Code DS2 ON, DS1 ON

Split & Multi-Split

DS2 ON, DS1 ON means different things on different Split & Multi-Split models. Enter your model number to see only your reading, or find your model below.

What It Means

  • EL16XP1, ML16KP2, ML16XP1: Demand Defrost Control Failure
  • XP19: Circuit Board Failure
  • XP15: DCB failure

Causes & actions from Lennox

Demand Defrost Control Failure

Models: EL16XP1, ML16KP2, ML16XP1

Heat pump (outdoor)

How it shows
  • defrost control ds2 ds1 led: DS2 ON, DS1 ON (ds1: on, ds2: on)

Indicates that demand defrost control has internal component failure. Cycle 24VAC power to demand defrost control. If code does not clear, replace demand defrost control.

Applicable models & manual sources

Circuit Board Failure

Models: XP19

How it shows
  • defrost control ds2 ds1 led: DS2 ON, DS1 ON (ds1: on, ds2: on)

Circuit Board Failure. Indicates that board has internal component failure.

Other manual wording

XP19

Circuit Board Failure. Indicates that board has internal component failure. Cycle 24 volt power to board. If code does not clear, replace board.

Applicable models & manual sources

DCB failure

Models: XP15

How it shows
  • defrost control ds2 ds1 led: DS2 ON, DS1 ON (ds1: on, ds2: on)

DCB failure: Indicates that DCB has internal component failure.

Applicable models & manual sources
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.

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