KOER Self-Test Not Able to Complete
2002-2005 Ford Explorer 4.6L V8 🇨🇦
Description
The Key On Engine Running (KOER) self-test was unable to complete. This indicates the PCM could not finish its powered-on engine running diagnostic routine, possibly due to another existing fault or test conditions not being met.
Symptoms
- Check Engine Light
- Self-test cannot complete
- Other DTCs may be stored
Common Causes
- Existing DTCs preventing test completion
- Engine not at operating temperature
- Accessories not turned off during test
- PCM malfunction
Diagnostic Steps
- Ensure engine is fully warmed up before running KOER test
- Turn off all accessories (A/C, lights, radio)
- Check for and resolve any other stored DTCs first
- Retry KOER self-test
Repair Notes
Resolve other DTCs first, then re-run KOER self-test with engine at operating temperature.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0001Fuel Volume Regulator Control Circuit/Open
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0003Fuel Volume Regulator Control Circuit Low
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
P1001 on Other Vehicles
Common Questions
What does code P1001 mean on a 2002-2005 Ford Explorer?
P1001 stands for "KOER Self-Test Not Able to Complete". The Key On Engine Running (KOER) self-test was unable to complete. This indicates the PCM could not finish its powered-on engine running diagnostic routine, possibly due to another existing fault or test conditions not being met.
What are the symptoms of P1001 on a Ford Explorer?
Common symptoms of P1001 include: Check Engine Light, Self-test cannot complete, Other DTCs may be stored.
What causes P1001 on a 2002-2005 Ford Explorer?
Common causes of P1001 include: Existing DTCs preventing test completion, Engine not at operating temperature, Accessories not turned off during test, PCM malfunction.