Symptom
Hybrid running on engine only
The petrol engine does all the work: no electric-only running, no electric assistance, and often a noticeable drop in economy. This is usually the hybrid system protecting itself — a fault in the motor, its sensors or the inverter benches the electric side while the engine carries on — so the car drives on but the reason it was bought stops happening.
Also described as: no ev mode, electric mode not working, no electric drive, ev mode unavailable, engine always running, no electric assist, hybrid not working, فقط با موتور بنزینی کار میکند, حالت برقی کار نمیکند, hibrido solo gasolina, no pasa a modo electrico, hibrido no usa bateria, الهجين يعمل بالبنزين فقط, لا يتحول للكهرباء, الوضع الكهربائي لا يعمل
What this usually means
This is usually the hybrid system protecting itself rather than the electric side having broken. A fault in the motor, its sensors, the inverter or the pack benches the electric half while the engine carries on — so the car drives on, and the reason it was bought stops happening. That combination is why the complaint often arrives weeks after the fault, once somebody notices the fuel bill.
The pack is the least likely cause and the first assumption, which is the pattern worth breaking. The system will withdraw electric operation for a cooling fault, an inverter temperature, a sensor it cannot verify, an isolation reading, or a 12 volt supply too weak for the contactors — none of which is the traction battery.
Start with the 12 volt battery even here. Low system voltage makes hybrid modules misbehave rather than stop cleanly, so a weak auxiliary battery produces hybrid faults in a perfectly healthy system. It is cheap, quick, and it is the same brown-out mechanism that produces a page of unrelated warning lights on a conventional car.
Then cooling, because owners never think of it. A pack cooling intake blocked with dust and pet hair behind a rear seat, or a failed electronics coolant pump, raises temperatures until the management restricts electric operation — and the repair is cleaning a filter or renewing a small pump.
Read the hybrid modules' own codes. A generic reader that sees only powertrain codes will report a clean car, because this fault is stored where it happened.
Working through it
| What you find | Likely cause | How to confirm it | What fixes it |
|---|---|---|---|
| Electric operation gone, hybrid warning lamp lit | A stored fault has disabled the electric side deliberately | Read the hybrid modules' own codes rather than generic powertrain ones. The code names the subsystem and usually the cost. | Diagnose the named fault. Do not assume the traction battery — it is the least likely of the candidates. |
| Electrical oddities elsewhere, or the 12 volt battery is old | Low 12 volt supply — hybrid modules misbehave rather than stop, so healthy systems report faults | Load or conductance test the 12 volt battery; voltage alone passes batteries that collapse under load. | Renew and register the 12 volt battery, clear the codes, re-scan. Only what returns is real. |
| Appeared after hot weather or sustained hard driving | Thermal protection — pack or inverter temperature above the limit for electric operation | Read live pack and inverter temperatures and cooling fan or pump duty. Find and inspect the pack's cooling intake. | Clean the intake filter and duct, or renew the failed coolant pump. This is a service item almost nobody knows exists. |
| Electric operation lost alongside a swinging charge gauge | The pack's usable window has narrowed enough that the system stops relying on it | Read per-block voltages and the minimum-to-maximum spread. This is the case where the pack genuinely is implicated. | Module-level repair by a qualified technician. One weak module is not a whole pack. |
| Lost after work near the high-voltage system | An interlock open or a connector not latched — the system has isolated the pack deliberately | Read interlock and isolation status. This is a safety response doing its job rather than a failure. | Latch the connector or cover properly. Qualified high-voltage work only beyond that point. |
| No lamp, no codes, and economy is merely worse than expected | Possibly nothing — cold weather, short journeys and a cold cabin all reduce electric operation legitimately | Compare against the vehicle's own history in similar conditions rather than against the brochure figure. | No repair. Preconditioning while plugged in, where the car supports it, recovers much of the difference. |
-
Electric operation gone, hybrid warning lamp lit
- Likely cause
- A stored fault has disabled the electric side deliberately
- How to confirm it
- Read the hybrid modules' own codes rather than generic powertrain ones. The code names the subsystem and usually the cost.
- What fixes it
- Diagnose the named fault. Do not assume the traction battery — it is the least likely of the candidates.
-
Electrical oddities elsewhere, or the 12 volt battery is old
- Likely cause
- Low 12 volt supply — hybrid modules misbehave rather than stop, so healthy systems report faults
- How to confirm it
- Load or conductance test the 12 volt battery; voltage alone passes batteries that collapse under load.
- What fixes it
- Renew and register the 12 volt battery, clear the codes, re-scan. Only what returns is real.
-
Appeared after hot weather or sustained hard driving
- Likely cause
- Thermal protection — pack or inverter temperature above the limit for electric operation
- How to confirm it
- Read live pack and inverter temperatures and cooling fan or pump duty. Find and inspect the pack's cooling intake.
- What fixes it
- Clean the intake filter and duct, or renew the failed coolant pump. This is a service item almost nobody knows exists.
-
Electric operation lost alongside a swinging charge gauge
- Likely cause
- The pack's usable window has narrowed enough that the system stops relying on it
- How to confirm it
- Read per-block voltages and the minimum-to-maximum spread. This is the case where the pack genuinely is implicated.
- What fixes it
- Module-level repair by a qualified technician. One weak module is not a whole pack.
-
Lost after work near the high-voltage system
- Likely cause
- An interlock open or a connector not latched — the system has isolated the pack deliberately
- How to confirm it
- Read interlock and isolation status. This is a safety response doing its job rather than a failure.
- What fixes it
- Latch the connector or cover properly. Qualified high-voltage work only beyond that point.
-
No lamp, no codes, and economy is merely worse than expected
- Likely cause
- Possibly nothing — cold weather, short journeys and a cold cabin all reduce electric operation legitimately
- How to confirm it
- Compare against the vehicle's own history in similar conditions rather than against the brochure figure.
- What fixes it
- No repair. Preconditioning while plugged in, where the car supports it, recovers much of the difference.
Codes that produce this symptom (202)
Listed with the codes that most typically present this way first — the likeliest place to start.
- P0A3F Drive Motor A Position Sensor Circuit Typical of this code High
- P0A41 Drive Motor A Position Sensor Circuit Low Typical of this code High
- P0A42 Drive Motor A Position Sensor Circuit High Typical of this code High
- P0AFD Hybrid/EV Battery Pack Temperature Too Low Typical of this code Moderate
- P0B25 Hybrid/EV Battery A Voltage Low Typical of this code High
- P0B29 Hybrid/EV Battery B Voltage Low Typical of this code High
- P0C05 Drive Motor A Phase U-V-W Circuit/Open Typical of this code High
- P0C06 Drive Motor A Phase U-V-W Circuit Low Typical of this code Moderate
- P0C07 Drive Motor A Phase U-V-W Circuit High Typical of this code Moderate
- P0C0B Drive Motor A Inverter Power Supply Circuit/Open Typical of this code High
- P0C0C Drive Motor A Inverter Power Supply Circuit Low Typical of this code Moderate
- P0C0D Drive Motor A Inverter Power Supply Circuit High Typical of this code Moderate
- P0DE4 Electric/Auxiliary Transmission Fluid Pump A Motor Over Temperature Typical of this code High
- P0DF0 Generator Inverter Temperature Sensor B Circuit Typical of this code High
- P0DF1 Generator Inverter Temperature Sensor B Circuit Intermittent/Erratic Typical of this code High
- P0DF2 Generator Inverter Temperature Sensor C Circuit Typical of this code High
- P0DF3 Generator Inverter Temperature Sensor C Circuit Intermittent/Erratic Typical of this code High
- P0DF4 Generator Inverter Temperature Sensor B Circuit Range/Performance Typical of this code High
- P0DF5 Generator Inverter Temperature Sensor B Circuit Low Typical of this code High
- P0DF6 Generator Inverter Temperature Sensor B Circuit High Typical of this code High
- P0DF7 Generator Inverter Temperature Sensor C Circuit Range/Performance Typical of this code High
- P0DF8 Generator Inverter Temperature Sensor C Circuit Low Typical of this code High
- P0DF9 Generator Inverter Temperature Sensor C Circuit High Typical of this code High
- P0DFA Generator Phase U-V-W Current Sensor Correlation Typical of this code High
- P0DFB Generator Position Exceeding Learn Limit Typical of this code High
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Others with this symptom
Be the first to write this up
Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.
What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
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