511 Read out memory test failure KOEO
How to read it
Code 511 reads as 5 flashes, pause, 1 flash, pause, 1 flash on the check-engine light. Jumper the self-test input to signal return at the test connector, then run the key on engine off self test and the running self test, counting the check-engine flashes each time.
New to flash codes? The OBD-I code reading guide walks through the paperclip method, code 12, and reading two-digit codes.
What does Ford code 511 mean?
511. Read out memory test failure KOEO. This code sets when your vehicle computer detects read out memory test failure koeo.
Common causes of 511
- Battery power was interrupted and the memory was cleared
- Open power feed or blown fuse to the PCM memory circuit
- Corroded or loose battery terminals and grounds
- Low charging system voltage
- Internal PCM memory fault
How to fix 511
- Confirm the code and note whether battery power was recently interrupted
- Check the battery cables, grounds and the PCM memory fuse
- Measure battery and charging voltage under load
- Clear the code and retest before condemning the PCM
- Replace the PCM only if the memory test fails again with good power and grounds