P0606 Control module processor fault
What P0606 means
The engine control unit has detected that its processor, or a cross-check between its processors, is not working correctly. On cars with electronic throttle this often triggers reduced-power mode for safety.
P0606 is a generic SAE J2012 code: it means the same on every make. The exact cause still depends on the car, so read the freeze-frame data before replacing parts.
At a glance
- Severity
- High
- Typical repair cost
- 150–1200 €
- Workshop time
- 1–8 h
- Repair difficulty
- Hard
- DIY possible
- No
- Check engine light
- Yes
- Affects emissions test
- No
- Limp mode possible
- Yes
Parts and labour at an independent workshop in Europe. Main dealers charge more; the cause decides the bill, not the code.
Symptoms
- Check engine light on
- Reduced power or limp mode
- Stalling or no start
- Throttle not responding normally
Common causes
- Internal engine control unit failure
- Poor battery voltage or ground connections
- Water or corrosion in the ECU connectors
- Outdated software with a known fault
Can I keep driving with P0606?
Have it checked within a day or two. The engine may go into limp mode or stop, which can be dangerous in traffic.
What to check first
- Check the battery, charging voltage and ECU grounds
- Inspect ECU connectors for water or corrosion
- Check for a software update for the control unit
- Repair or replace the control unit if the fault remains
Related codes
- P0605 Internal control module read only memory (ROM) error
- P0607 Control module performance
- P0604 Internal control module random access memory (RAM) error
- P0603 Internal control module keep alive memory (KAM) error
- P0602 Control module programming error
- P0601 Internal control module memory checksum error
- P0600 Serial communication link
- P0610 Control module vehicle options error
Data: TORKO fault-code catalogue, built on OBDex (CC0-1.0) and reviewed against workshop practice. Informational only — it does not replace a diagnosis by a mechanic.
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