What you will see
- Warning 203 after installation or adding panels
- One input shows nothing
Why it happens
Reversed polarity or a damaged connector on one string makes the inverter flag that input.
Diagram
One input flagged
Correct
String+ to +, − to −
→PV inputUsed
Reversed or damaged
StringWrong way or bad connector
→PV1 / PV2Warning 203
What you can check yourself
- Note which input (PV1 or PV2) and any recent work
What not to do
- Do not reconnect or swap PV connectors yourself
When to call us
- Check polarity and connectors safely
- Correct the string and recheck
After roof work
If this appeared after another installer worked on your roof, our Faisalabad and Lahore engineers can correct it.
Send us
the alarm photo and when panels were last changed