# C1991 on the 2004 Ford Freestar

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

- [10008251](https://open.wenmarpro.com/bulletins/10008251), 2004-07-24: DIAGNOSTIC TROUBLE CODE \(DTC\) C1991 \(MODULE CALIBRATION FAILURE\) \- ANTI\-LOCK BRAKE, ADVANCED TRAC, INTERACTIVE VEHICLE DYNAMICS \(IVD\), TRACTION CONTROL SYSTEM \- SERVICE TIP. ALSO INCLUDES FORD FREESTAR MY2005 AND MERCURY MONTEREY MY2005. \*TT