OBD-I Codes List

Ford 56 Transmission fluid temperature circuit open or mass air flow sensor above maximum voltage

Make
Ford (1981-1995)
Category
Powertrain - Fuel/Air Metering
Severity
Check Engine Light

How to read it

Code 56 reads as 5 flashes, pause, 6 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 56 mean?

Transmission fluid temperature circuit open or mass air flow sensor above maximum voltage

Common causes of 56

  • Wiring short circuit to positive
  • MAF sensor
  • ECM

How to fix 56

  1. Check the circuit wiring for a short to power
  2. Test the MAF sensor and replace it only if it fails its own test
  3. Test the ECM last, only after every circuit test has passed
  4. Clear the code, then retest to confirm the fix holds

Source

Source review recorded

Sources and review

Review: checked against the recorded source material.

Last updated 2026-09-29.

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