# C1991 on the 2003 Ford Expedition

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

This code is specific to a manufacturer and is not described here.

## Bulletins for this model year that name C1991

- [10013083](https://open.wenmarpro.com/bulletins/10013083), 2005-04-07: DIAGNOSTICS FOR DIAGNOSTIC TROUBLE CODE C1991 IN THE ABS \(ANTILOCK BRAKE SYSTEM\) MODULE \- OMITTED FROM WORKSHOP MANUAL \- PROCEDURE PROVIDED. \*TT
- [10003727](https://open.wenmarpro.com/bulletins/10003727), 2003-10-29: THIS ARTICLE ADDRESSES THE PROPER PROCEDURE TO CLEAR DIAGNOSTIC TROUBLE CODES C1990 OR C1991 FROM THE VEHICLE DYNAMICS MODULE/4\-WHEEL AIR SUSPENSION MODULE. \*TT
- [636271](https://open.wenmarpro.com/bulletins/636271), 2002-11-07: DIAGNOSTIC PROCEDURES FOR DIAGNOSTIC TROUBLE CODE C1991 \(MODULE CALIBRATION FAILURE\) OMITTED FROM THE WORSHOP MANUAL. \*TT