What causes Ford code 225?

The knock sensor did not report knock during the KOER dynamic response test. The knock sensor wiring to the ECM is open or damaged. The knock sensor connector is loose or corroded. The ECM did not register the knock signal.

How do I fix Ford code 225?

Check the knock sensor mounting and confirm it is tight against the block. Check the wiring and connector between the knock sensor and the ECM. Test the knock sensor and replace it only if it fails its own test. Test the ECM last, only after every circuit test has passed. Clear the code, then retest with the engine running to confirm the knock signal is sensed.

Ford 225 Knock not sensed during dynamic response test KOER

Q: What does Ford code 225 mean?

Ford code 225. Knock not sensed during dynamic response test KOER.

Make: Ford (1981-1995)
Category: Powertrain - Ignition
Severity: Check Engine Light

How to read it

Code 225 reads as 2 flashes, pause, 2 flashes, pause, 5 flashes 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 How to Read Ford EEC-IV Self-Test Codes walks through the test and what the numbers mean. The general OBD-I guide covers the rest.

What does Ford code 225 mean?

Knock not sensed during dynamic response test KOER

Common causes of 225

The knock sensor did not report knock during the KOER dynamic response test.
The knock sensor wiring to the ECM is open or damaged.
The knock sensor connector is loose or corroded.
The ECM did not register the knock signal.

How to fix 225

Check the knock sensor mounting and confirm it is tight against the block.
Check the wiring and connector between the knock sensor and the ECM.
Test the knock sensor and replace it only if it fails its own test.
Test the ECM last, only after every circuit test has passed.
Clear the code, then retest with the engine running to confirm the knock signal is sensed.

Source

Source review recorded

Sources and review

Review: checked against the recorded source material.

EEC-IV Ford trouble code table (MIL, description, type)
archived reference page (troublecodes.net via Wayback Machine)
Supports: code identity and meaning
Fetched directly. The three-digit row matches the description used in the data file.
https://web.archive.org/web/20030720231430id_/http://www.troublecodes.net:80/Ford/eec-iv.shtml
Ford trouble codes, Contour, Escort, Mustang, Probe, Taurus and Tempo 1992-1995 (code, description, probable cause)
archived reference page (troublecodes.net via Wayback Machine)
Supports: code identity and probable causes
Independent table on the same archive site with matching code identity and a probable cause column.
http://web.archive.org/web/20160501223306id_/http://www.troublecodes.net:80/ford/contour-escort-mustang-probe-taurus-tempo-1992-1995/
Ford EEC-IV trouble code table: code, fault location, probable cause (Crown Victoria, Mustang, Taurus, Thunderbird 1992-1995)
reference page (troublecodes.net)
Supports: per-code probable causes used for the page cause list and test order
Fetched 2026-09-30. The probable cause column is what the page lists, in source order, with the test order built from it.
https://www.troublecodes.net/ford/crown-victoria-mustang-cobralxgt-taurus-thunderbird-1992-1995/

Last updated 2026-10-10.

Report a correction for 225. Include your vehicle, the issue and a source if you have one.