P064DInternal Control Module O2 Sensor Processor Performance Bank 1
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- Wide-band oxygen sensors need a pump current control; inside the engine module a dedicated chip (ASIC, for example Bosch's CJ125 family) regulates it, measures lambda, diagnoses sensor wiring and heater, and talks to the main processor via SPI. P064D means this chip for bank 1 sensor 1 does not work correctly or its messages are invalid. Ford validates the SPI communication continuously and sets P064D/P064E after 10 s at 11–18 V with the sensor heater working; an internal chip fault adds Ford's P1646/P1647. GM (wide-band engines such as the 3.0 L twin turbo, 2018–2025) evaluates two error counters from the chip and sets the code at 128 of 160 samples (about 4 s), more than 20 s after start-up, with the lamp after two trips. Fuel control then runs open loop and oxygen sensor monitors are disabled – fuel consumption and emissions rise. Faults in the sensor or wiring can also push the chip into an invalid state.
- What you may notice
- Check engine light
- Higher fuel consumption, rough running (open loop)
- Failed emissions test
- Codes for the bank 1 sensor 1 wide-band sensor
- Likely causes
- LikelyEngine module (lambda chip) faulty
- PossibleWiring or sensor fault pushing the chip into an invalid state (short to battery voltage, water in connector)
- PossibleFaulty wide-band sensor (e.g. heater-to-signal short)
- RareVoltage dips or software
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €150 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.