P0E73: Control Pilot Signal High Frequency
What to do
Try a different charge point first — that separates the car from the supply in one test. If it happens everywhere, mention any water ingress or damage around the charging inlet; a noisy pilot signal is very often a poor earth or a wet connector rather than a faulty part.
What this code means
The Control Pilot signal's frequency is above specification.
The Control Pilot is a 1 kHz square wave, and the frequency is not decoration — it is how the car knows the signal is a real pilot rather than noise.
The full handshake is at P0CF3. In short: the charge point puts a square wave on one pin, and the pulse width states how much current the car may draw; the car replies by switching resistors to pull the voltage down in defined steps. A charge point will not energise the cable until it sees a valid reply.
The frequency is the carrier that whole conversation rides on, and the standard pins it at 1 kHz precisely so that width can be measured against it. Measuring a pulse width means comparing it against the period — so a frequency that has drifted makes every current limit the car calculates wrong, not merely suspect.
Which is why this code usually means the supply rather than the car. A vehicle measuring an out-of-specification frequency is reporting on the equipment it is plugged into, and the single most useful test is another charge point.
High frequency is rarer and more often the car's measurement than the supply's signal. A charge point's pilot generator is usually crystal-derived and does not drift upward on its own; a car reading it high is frequently reading noise superimposed on the signal rather than a genuinely fast wave.
That points at the pilot conductor's shielding and its earth — a pilot line running alongside a high-current charging cable picks up interference readily, and a degraded earth is what stops that interference being drained away. Water in the inlet does the same thing, which is why this and P0DAA share a cause list.
Likely causes
Start here
- Damaged charging inlet or pins · moderate
- Water ingress into connector · specialist
- Corroded or loose connector · specialist
Less common
- Fault in the external charging equipment · easy
- Corroded earth connection · moderate
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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