Warning 203 on a Growatt inverter: PV1 or PV2 circuit short
Short answer
On a Growatt inverter, Warning 203 means: PV1 or PV2 circuit short. The inverter stops until the fault clears or is reset. An engineer is needed to fix the cause. The wording differs by model range — each is shown below.
Reviewed 24 September 2026 · 2 sources
What it means
On the MIN 2500-6000TL-X
The manual says: PV1 or PV2 circuit short.
Part involved: PV input over-voltage.
Likely causes:
- PV polarity / short.
On the SPH 3000-6000TL BL-UP (48 V battery hybrid)
The manual says: PV1 or PV2 Circuit short - check PV polarity.
Part involved: PV input over-voltage.
Likely causes:
- check PV polarity.
Is it safe?
Switch the inverter off at its isolator and call an engineer.
| Does the inverter stop? | Yes |
|---|---|
| Severity | Safety lockout |
| Engineer needed? | Yes |
The inverter stops until the fault clears or is reset.
Resetting itself: no.
Manual reset: yes, after string design is corrected.
What you can check
- Read and note the exact code and time from the inverter display or app (screenshot).
- Call the installer. Do not touch DC cabling.
- Growatt's manual says 'restart inverter'. A homeowner can switch the inverter off and on at its AC isolator/breaker; leave DC switching to the installer unless the manual step says to switch DC off immediately (Error 202).
What the engineer will check
- Measure open-circuit string voltage (cold-weather Voc rise).
- Check string design against inverter max DC voltage.
- Check for mixed/incorrect module counts.
Who to ask for: PV installer / system designer.
Certification: Electrician competent in grid-connected PV (BS 7671 Section 712; IET Code of Practice for Grid-connected Solar PV), ideally the original MCS-certified PV installer; brand-approved/trained installer to keep manufacturer warranty.
What you might notice
Sources
- Growatt MIN 2500-6000TL-X Installation & Operation (User) Manual, general EN 2022-06 ↗ · EN 202206 · page PDF p.23 · Reviewed 24 September 2026
- Growatt SPH 3000-6000TL BL-UP User Manual EN 202512 ↗ · EN 202512 · page PDF p.61 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026