Error code reference

Lennox Furnace Error Code DS1 Alternating Fast Flash / DS2 Alternating Fast Flash

During ignitor warm-up period only: improper main ground; OR broken ignitor/open ignitor circuit; OR line voltage below 75 volts. (G32V-5 units)

SourceLennox G32V Series Furnace - Service ManualTable 21, Page 25

Lennox codes Lennox furnace codes

Diagnostic procedure

The full DS1 Alternating Fast Flash / DS2 Alternating Fast Flash procedure

Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.

MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

Check unit ground, line voltage, and ignitor circuit.

SourceLennox G32V Series Furnace - Service ManualTable 21, Page 25

Unlock with pass

More steps, wiring diagram references, and verified part numbers

Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.

Unlock DS1 Alternating Fast Flash / DS2 Alternating Fast Flash procedure $9.95

Or subscribe: $29/month for all codes plus Max diagnostics, with 70 Max messages a day. Plus applicable tax.

Where this code is documented

4 manuals in the MyPros+ library document this code for Lennox furnace.

Models covered by the manuals that document this code

75,000+ service documents · 20,000+ error codes · 100+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass · Plus applicable tax

The full DS1 Alternating Fast Flash / DS2 Alternating Fast Flash procedure

Where this code is documented

Models covered by the manuals that document this code

Related Lennox furnace error codes