What P0605 means
Internal Control Module Read Only Memory (ROM) Error
Common causes (general)
Before spending money on parts, verify the code with a scan tool and read freeze frame data. Freeze frame captures every sensor value at the moment the code set — this is often enough to figure out the root cause without further testing.
Manufacturer-specific descriptions
Different manufacturers use this code for slightly different failure modes. Here's what your specific make means by P0605:
| AUDI | Lack of proper voltage and or ground to the PCM, Defective PCM ROM memory module, Defective PCM ground circuit(s), Defective PCM controlled output devices |
| BMW | Internal Control Module Read Only Memory (ROM) Error |
| FORD | Powertrain Control Module ROM Test Error |
| MITSUBISHI | Internal Control Module ROM Error (Module Identification Defined by SAE J1979); ECU CPU malfunction flash ROM |
| NISSAN | Internal Control Module ROM Error (Module Identification Defined by SAE J1979) |
| VOLKSWAGEN | Control Module Programming Read Only Memory (ROM) |
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