U0156 code meaning
Lost Communication With Information Center A
What U0156 means
U0156 concerns information center A, the display and infotainment unit that shows messages, audio, navigation or vehicle settings. Two makers document the code. Mazda calls the partner the connectivity master unit, its infotainment head unit: on 2019-20 Mazda3 and CX-30 the vehicle and body controllers store U0156:00 with an in-vehicle network malfunction message (SA-029/20), and on 2024-25 CX-90 and CX-70 the engine controller logs it alongside a blank center screen, dark interior lights and a start only with the key held near the button, because the 25 A fuse F1 removed for transport was not fully seated (SA-040/24). Volvo's central electronic module sets U015600 on 2011-15 S60, S80, XC60 and XC70 when the Sensus screen stays black after a memory chip fault (TJ 25872). U0157 is center B, U0457 invalid data from A.
U0156 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.2 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0156
- Center display black, no audio or navigation
- Network malfunction or several warning messages in the cluster
- Climate or vehicle settings that run through the screen unavailable
Common causes of U0156
- Most likelySupply fuse of the unit missing or not fully seated (Mazda SA-040/24)
- PossibleInfotainment unit internally faulty, for example memory chip (Volvo TJ 25872)
- PossibleInfotainment software hangs or needs an update
- Less likelyBus wiring or connector behind the dash faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Information display moduleCAN bus wiring
What each part of U0156 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 U0156 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 U0156
What does U0156 mean?
U0156 means "Lost Communication With Information Center A". U0156 concerns information center A, the display and infotainment unit that shows messages, audio, navigation or vehicle settings. It is a generic code, so it means the same on every make.
Is it safe to drive with U0156?
U0156 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0156 fail an emissions test?
U0156 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 U0156 to fix?
Difficulty: medium. A typical repair takes 0.2 to 3 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will U0156 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.