Powertrain, generic

P0E72 Control Pilot Signal Low Frequency

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

P0E72 refers to the pulse train that an AC charging station places onto the pilot wire. Under SAE J1772, matched by IEC 61851-1, this is a rectangular ±12 V signal at 1 kHz, and its duty cycle tells the car how much current it may draw. The vehicle measures the period of this signal; if it is clearly slower than 1 kHz, the reading is distrusted and P0E72 is stored, because a wrong frequency also makes the current limit unreliable. No manufacturer documents P0E72 publicly. A US Department of Energy test report on pilot-line communication (PNNL) treats the 1000 Hz frequency and pulse width as values that added equipment must not disturb. Causes are a faulty station or adapter, interference on the line, or the car's measuring circuit. P0E73 is the high case; voltage faults are P0CF4 to P0CF6.

Likely causes

Charging station or portable charger generating an off-spec pilot
Faulty charging adapter or extension in the cable path
Pilot measuring circuit in the vehicle charger misreading

Symptoms

  • AC charging does not start or stops at one station
  • Charging works normally at other stations

Repair estimate

DifficultyEasyDIY possible
Parts and labour€0–600
Time0.2–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

control pilot signalevse

Related codes

P0E73P0CF4P0CF3

References: en.wikipedia.org, pnnl.gov, typhoon-hil.com.