U0556 code meaning
Invalid Data Received From Front Display Interface Module
What U0556 means
The front display interface module is the screen unit in the center of the dash; GM calls the matching node info display module (Saab 9-5 2011, U0255), Ford uses FDIM. The display mostly shows what other modules feed it. Ford examples: on the Escape (2016–2019) and Focus/C-Max (2016–2018) the FDIM ramps its backlight up and down in auto-dim mode, which looks like flicker but is normal (SSM 47748); on the 2020 Aviator the APIM configuration made the FDIM show the wrong number of radio presets (SSM 49092). U0556 is set by a receiver that gets FDIM frames, e.g. touch inputs or status, with implausible content; U0255 covers silence, U0558 the combined controls/display unit. No manufacturer documents U0556. Touch inputs may be ignored or the screen may act oddly.
U0556 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0556
- Touchscreen does not respond or reacts to inputs that were not made
- Wrong or incomplete content shown on the center display
Common causes of U0556
- PossibleDisplay module software fault or level not matching the infotainment unit
- PossibleWrong configuration of display or infotainment module after replacement or update
- Less likelyFront display module internally faulty (touch sensor or electronics)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Front display interface module
What each part of U0556 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 56 | The exact fault in that area. |
What to do next
- Note U0556 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U0556
What does U0556 mean?
U0556 means "Invalid Data Received From Front Display Interface Module". The front display interface module is the screen unit in the center of the dash; GM calls the matching node info display module (Saab 9-5 2011, U0255), Ford uses FDIM. It is a generic code, so it means the same on every make.
Is it safe to drive with U0556?
U0556 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0556 fail an emissions test?
U0556 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U0556 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will U0556 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.