Vehicle applicability: This diagnostic supplement covers multiple Ford vehicles and engines. Follow the application named in the source below. Some references apply to vehicles other than Mustang.
DF: Vehicle Speed Circuit (VSC) Check
DF: Introduction
DF1 CHECK FOR DTCS
Is DTC U0121 present?
Yes | No |
|---|---|
GO to DF2 . |
DF2 VISUAL INSPECTION
• Carry out the ABS self-test.
Are any DTCs present?
Yes | No |
|---|---|
REFER to the Workshop Manual Section 206- 09, Vehicle Dynamic Systems, to continue diagnosis of the ABS. | GO to DF3 . |
DF3 CHECK THE PCM VEHICLE SPEED SIGNAL INPUT
WARNING: STRICT OBSERVANCE OF POSTED SPEED LIMITS AND ATTENTION TO DRIVING CONDITIONS ARE MANDATORY WHEN CARRYING OUT THE ROAD TEST. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.
• Access the PCM and monitor the VSS (SPD) PID.
• Road test the vehicle while monitoring the VSS PID.
Does the VSS PID increase and decrease while driving?
Yes | No |
|---|---|
The concern is not present at this time. CHECK for a loose connection, and damaged or corroded pins. WIGGLE the harness attempting to recreate the concern. REPAIR as necessary. Clear the PCM DTCs. REPEAT the self-test. | GO to DF4 . |
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.