Code Description
WARNING: This page is about a different car, the 2009 Ford RV Cutaway, 2009 Ford Econoline, 2009 Ford E450 Super Duty, and 2009 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
The ABS module needs to be calibrated whenever a component specific to the Electronic Stability Control (ESC) or Roll Stability Control (RSC®) system is disconnected or a new component is installed. Calibration allows the ABS module to identify the "zero position" of the sensors so the system will operate correctly.
- DTC C1991 (Module Calibration Failure) - If the IVD Initialization sequence does not finish or if the ABS module loses the calibration information, DTC C1991 will be set.
This pinpoint test is intended to diagnose the following:
- ABS module
- Restraints Control Module (RCM)
- Steering wheel rotation sensor