P0A5F: Drive Motor A Phase U Current High
What to do
Expect a harder, quicker shutdown than the Low variant — that is the module protecting against real heat. The insulation test is the key measurement; ask for it by name. No home investigation.
What this code means
Phase U's current is running above what was commanded — the direction of shorts: insulation leaking between windings or to ground, a chafed cable finding the body, or an inverter switch conducting when it should not.
High is the less patient direction, because excess current makes heat wherever the leak is. The module typically cuts the motor quickly rather than derating gently. Diagnosis is the P0A5D list with the short-circuit half emphasised, and the insulation measurement is close to definitive here.
Likely causes
Start here
- Motor winding insulation breakdown · specialist
- Damaged high voltage phase cable or terminal · specialist
Less common
- Faulty power inverter · specialist
Symptoms
Components involved
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.
Community experience
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