What causes Ford code 47?

The four wheel drive selector switch stayed closed during the self test. The four wheel drive switch wiring is shorted. The transfer case has internal damage. Measured air flow is low at base idle. The ECM sees the four wheel drive switch closed when it should be open.

How do I fix Ford code 47?

Check the four wheel drive selector switch and confirm it is open during the self test. Check the four wheel drive switch wiring for a short. Check the transfer case for internal damage. Check the air flow reading at base idle against spec. Test the ECM last, only after every circuit test has passed. Clear the code, then retest to confirm the switch and the air flow read correctly.

Ford 47 Four wheel drive switch closed during self test or measured air flow low at base idle

Q: What does Ford code 47 mean?

Ford code 47. Four wheel drive switch closed during self test or measured air flow low at base idle.

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

How to read it

Code 47 reads as 4 flashes, pause, 7 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 47 mean?

Four wheel drive switch closed during self test or measured air flow low at base idle

Common causes of 47

The four wheel drive selector switch stayed closed during the self test.
The four wheel drive switch wiring is shorted.
The transfer case has internal damage.
Measured air flow is low at base idle.
The ECM sees the four wheel drive switch closed when it should be open.

How to fix 47

Check the four wheel drive selector switch and confirm it is open during the self test.
Check the four wheel drive switch wiring for a short.
Check the transfer case for internal damage.
Check the air flow reading at base idle against spec.
Test the ECM last, only after every circuit test has passed.
Clear the code, then retest to confirm the switch and the air flow read correctly.

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. Code 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 EEC-IV trouble codes, Crown Victoria, Mustang, Taurus, Thunderbird 1992-1995 (code, fault location, 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 additional probable causes.
https://web.archive.org/web/20160502051413id_/http://www.troublecodes.net:80/ford/crown-victoria-mustang-cobralxgt-taurus-thunderbird-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 47. Include your vehicle, the issue and a source if you have one.