Dometic Air Conditioner: “P2 / P3”
warning RV air conditioner error codes
What it means
P2 is AC over-current protection (the unit is drawing more current than allowed). P3 is over-voltage protection (incoming supply voltage too high). Both trip the unit off to protect the electronics.
Most likely causes
- P3: campsite/shore supply voltage above the unit's allowed range common
- P2: abnormal current draw from a compressor or wiring fault common
- Unstable or out-of-spec power source common
Safe checks you can do yourself
- For P3, ask campsite management or check whether the pedestal voltage is too high; relocate to a properly regulated supply if possible
- Confirm the unit is connected to a correctly wired, in-spec power source
- Restart on a known-good supply
How to reset / clear P2 / P3
- Disconnect power for about 2 minutes
- Restore a verified in-spec supply and restart
When to call a technician
P2 over-current almost always needs a technician (compressor/wiring). For P3, if the supply voltage is verified normal, contact an authorized Dometic service agent.
Applies to
Dometic FreshJet Series 4 (FJX) · Dometic FreshJet Series 7 (FJX) · FreshJet inverter rooftop units
FAQ
What does Dometic Air Conditioner code "P2 / P3" mean?
P2 is AC over-current protection (the unit is drawing more current than allowed). P3 is over-voltage protection (incoming supply voltage too high). Both trip the unit off to protect the electronics.
How do I reset Dometic Air Conditioner P2 / P3?
Disconnect power for about 2 minutes Restore a verified in-spec supply and restart
What is the most common cause of P2 / P3 on a Dometic Air Conditioner?
The most likely cause is p3: campsite/shore supply voltage above the unit's allowed range.
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Sources
- Dometic FreshJet Series 4 / Series 7 Operating Manual — 9620001685, Troubleshooting section, display codes P2 and P3 (Dometic)
Note: FreshJet FJX inverter models only. P2 and P3 grouped here as a current/voltage protection pair; they are two separate codes in the manual.
● Last verified 2026-06-29 · compiled from manufacturer documentation. Codes can vary by model year — always cross-check your unit’s manual.