Operation CHARM: Car repair manuals for everyone.
Home >> Ford >> 2008 >> E 250 V8-4.6L >> Repair and Diagnosis >> Brakes and Traction Control >> Antilock Brakes / Traction Control Systems >> Testing and Inspection >> Pinpoint Tests >> Test O: DTC C1991 - Module Calibration Failure
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Test O: DTC C1991 - Module Calibration Failure

Pinpoint Test O: DTC C1991 - Module Calibration Failure

Normal Operation
The ABS module needs to be calibrated whenever a component specific to the roll stability control (RSC) system or electronic stability control (ESC) 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.

This pinpoint test is intended to diagnose the following:
^ ABS module
^ Sensor cluster
^ Steering wheel rotation sensor

O1-O4:




pro multis · About Operation CHARM