⚡ How to read your fault code: Plug an OBD-II diagnostic tool into your vehicle's OBD port (under the dashboard). The displayed code corresponds to a specific anomaly detected by the ECU. Include it in your quote request — our experts can then immediately direct you to the right service.
C1241
Insufficient battery voltage
Faulty 12V battery or charging circuit
🔴 Observed symptoms
- Check Engine light or service required message
- ABS warning light on
🔧 Possible causes
- Battery charge level too low
- Faulty 12V battery
- Charging circuit malfunction
P3011
→ P3027
→ P3027
Battery module failure
Toyota Prius 2007–2015 — High Voltage pack
🔴 Observed symptoms
- Increased fuel consumption
- Degraded HV battery efficiency
🔧 Possible causes
- Overall high voltage battery pack failure
- Deterioration of one or more modules
(P3011 = module 1, P3012 = module 2, etc.)
📋 Module mapping
P3011 — Module 1
P3012 — Module 2
P3013 — Module 3
P3014 — Module 4
P3015 — Module 5
P3016 — Module 6
P3017 — Module 7
P3018 — Module 8
P3019 — Module 9
P3020 — Module 10
P3021 — Module 11
P3022 — Module 12
P3023 — Module 13
P3024 — Module 14
P3025 — Module 15
P3026 — Module 16
P3027 — Module 17
P3000
Battery management system anomaly
High Voltage management failure
🔴 Observed symptoms
- Check engine light with warning triangle
🔧 Possible causes
- High voltage management system failure
- Fuel level too low
- Issue affecting the hybrid battery
P0A80
Hybrid battery needs replacing
⚠️ Replacement or refurbishment required
🔴 Observed symptoms
- Excessive fuel consumption
- Reduced performance and acceleration
🔧 Possible causes
- Faulty high voltage battery or internal modules
- Faulty cooling fan or battery management unit
- Poor electrical contacts (oxidised or loose connectors)
P0A7F
Hybrid battery degradation
Reduced performance — Refurbishment possible
🔴 Observed symptoms
- Gradual loss of vehicle performance
- Abnormally fast HV battery charge and discharge cycles
- Hybrid warning light on dashboard
🔧 Possible causes
- Natural ageing of the high voltage battery pack
- One or more heavily degraded modules
- Charge imbalance between cells
P0A78
MG2 motor-generator malfunction
Faulty traction electric motor
🔴 Observed symptoms
- Reduced available electric power
- Orange warning triangle light on
- Safety mode active (reduced power)
🔧 Possible causes
- MG2 motor-generator failure
- HV inverter issue
- Electrical system overheating
P0A93
Inverter cooling circuit failure
HV thermal management system compromised
🔴 Observed symptoms
- Hybrid compartment overheating
- Automatic performance reduction
- Warning message on dashboard display
🔧 Possible causes
- Failed inverter cooling pump
- Leak or insufficient HV coolant level
- Cooling circuit blockage
P0A94
Insufficient pressure in HV cooling circuit
Hydraulic fault on high voltage circuit
🔴 Observed symptoms
- Hybrid or engine warning light on
- Erratic charging system behaviour
🔧 Possible causes
- Faulty cooling pump
- Leak in dedicated HV electronics cooling circuit
- Faulty pressure sensor
P0AC4
HV battery relay fault (main contactor)
High voltage power circuit interrupted
🔴 Observed symptoms
- Vehicle in limp-home mode or unable to start
- Red READY light unavailable
- Sudden hybrid system shutdown
🔧 Possible causes
- Main contactor (HV relay) faulty or burnt out
- Short circuit in high voltage wiring
- Battery pack insulation fault
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