P0602 Control module programming error
What P0602 means
The engine control unit reports that it does not have valid software or calibration loaded. This is most often seen after a control unit has been replaced or a software update was not completed.
P0602 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
- Medium
- Typical repair cost
- 80–800 €
- Workshop time
- 0.5–4 h
- Repair difficulty
- Hard
- DIY possible
- No
- Check engine light
- Yes
- Affects emissions test
- No
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
- Engine may not start
- Poor running or limp mode
Common causes
- Replacement control unit not programmed
- Software update interrupted, for example by low battery voltage
- Wrong software loaded for the vehicle
- Internal control unit fault
Can I keep driving with P0602?
You can drive if the engine runs normally, but have it checked within one to two weeks. If it was recently updated or replaced, return to the workshop that did the work.
What to check first
- Find out whether the control unit was recently replaced or updated
- Check battery voltage and grounds
- Have the control unit programmed with the correct software for the VIN
- Replace the control unit if it will not accept programming
Related codes
- P0601 Internal control module memory checksum error
- P0603 Internal control module keep alive memory (KAM) error
- P0600 Serial communication link
- P0604 Internal control module random access memory (RAM) error
- P0605 Internal control module read only memory (ROM) error
- P0606 Control module processor fault
- P0607 Control module performance
- 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.
Updated: