527 Neutral drive switch circuit open, A/C on

Make
Ford (1981-1995)
Category
Powertrain - Computer and Auxiliary Controls
Severity
Check Engine Light
Applies to
1981-1995 Ford, Lincoln and Mercury EEC-IV vehicles

How to read it

Code 527 reads as 5 flashes, pause, 2 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 OBD-I code reading guide walks through the paperclip method, code 12, and reading two-digit codes.

What does Ford code 527 mean?

527. Neutral drive switch circuit open, A/C on. This code sets when your vehicle computer detects neutral drive switch circuit open, a/c on.

Common causes of 527

How to fix 527

  1. Confirm the code and read the flash sequence again
  2. Check the park neutral switch adjustment
  3. Inspect the park neutral switch and its wiring for damage and corrosion
  4. Test the switch for a correct state change
  5. Repair wiring or replace the switch only after the test fails