Skip to main content
Error code reference
LG HVAC Error Code 5
Communication error between IDU and ODU PCB.
SourceLG Ductless HVAC & PTAC - Tech Sheet: Error Codes & Wiring
Diagnostic procedure
The full 5 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
1
First diagnostic step
Check wiring (123 or 1234 wires at ODU must be same color as at IDU; polarity sensitive). Inverters: voltage on wires 2 & 3 must float between 0-65V DC. 10/13 SEER: voltage on wires 3 & 4 (or 1 & 2 for Flex Multi) must float 0-12V DC. Do NOT use auto-detect AC/DC volt meter. Check all fuses at IDU/ODU.
SourceLG Ductless HVAC & PTAC - Tech Sheet: Error Codes & Wiring
More steps, wiring diagram references, and verified part numbers
Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.
Unlock 5 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
1 manual in the MyPros+ library documents this code for LG hvac.
Models covered by the manuals that document this code
- LAU090HYV
- LAU120HYV
- LAXXXHSV
- LAXXXHSV2
- LMO240
- LMO360
- LMUXXXHV
- LSN091HSV3
- LSN121HSV3
- LSN181HSV3
- LSN240HSV
- LSN240HSV2
- LSN240HSV3
- LSN305
- LSN306
- LSN307
- LSN360
- LSU091HSV3
- LSU121HSV
- LSU181HSV3
- LSU240HSV3
- LSU307HV3
- LSU360HV3
- LSXXXHSV
More models are covered than are listed here.
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