SPH 3000–6000TL BL-UP / SPH 4000–10000TL3 BH-UP hybrid (Error 2xx–6xx codes)
Growatt Warning 203 error code
PV1 or PV2 input is detected as a short circuit (Warning 203 — distinct from Error 203, which is PV isolation low).
Likely causes
- PV positive and negative reversed at the input
- Shorted or water-filled MC4 connector
- Damaged DC cable or panel junction box
- Shorted panel string
Checks to run, in order
- 1Check whether the positive and negative poles of the PV input are reversed
- 2Inspect and reseat the PV connectors
- 3Isolate PV1 and PV2 and measure each string for a short
- 4Check panel junction boxes and cable insulation
Fixes
- Reconnect the PV connectors with correct polarity
- Replace damaged connectors or DC cable
- Restart the inverter and confirm the warning clears
When to escalate
If the PV inputs are correctly wired and the warning persists after reseating, ask Growatt support to check the PV input detection circuit.
Fix it with the right tools
Check the system around the fault before replacing parts: load, battery bank, PV string and commissioning settings. If you need a second opinion, send the code and your inverter model to our team.
Before you open the inverter
- Isolate both the AC and DC sides, then confirm the display is dead before touching terminals.
- Use insulated tools and one hand where possible. DC arcs do not self-extinguish like AC.
- If you see burnt terminals, swollen cells, leaking electrolyte or a burning smell, stop and escalate instead of resetting the fault.
Questions installers ask
What does Growatt Warning 203 mean?
PV1 or PV2 input is detected as a short circuit (Warning 203 — distinct from Error 203, which is PV isolation low).
How do I fix Growatt Warning 203?
Reconnect the PV connectors with correct polarity Replace damaged connectors or DC cable Restart the inverter and confirm the warning clears
When should I escalate Growatt Warning 203?
If the PV inputs are correctly wired and the warning persists after reseating, ask Growatt support to check the PV input detection circuit.
Can I reset Growatt Warning 203 myself?
Only after isolating the AC and DC sides and running the checks above. If Growatt Warning 203 returns immediately, stop resetting it and escalate; a repeating fault usually points to a real circuit, battery or hardware problem.
Which models show Growatt Warning 203?
Growatt Warning 203 is documented for SPH 3000–6000TL BL-UP / SPH 4000–10000TL3 BH-UP hybrid (Error 2xx–6xx codes). Confirm the code on your own unit's display or manual before ordering parts.
More Growatt error codes
- Growatt 01Fan is locked (displayed as F01 on the SPF ES Lite).
- Growatt 02Internal component temperature is over 100 °C (F02 on the ES Lite).
- Growatt 03Battery is over-charged / battery voltage is too high (F03 on the ES Lite).
- Growatt 04Battery voltage low.
- Growatt 05Output is short-circuited (F05 on the ES Lite).
- Growatt 06Output voltage is too high. The manual groups 06/58 as 'output abnormal' — inverter voltage above 150 Vac or below 40 Vac.
Guidance reviewed 17 October 2026 by the Mishka Energy installer team. Error codes vary by brand, model family and firmware; confirm against the manufacturer manual.
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