Network, generic

U056D Invalid Data Received From Image Processing Sensor H

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U056D is reported when sensor H's messages carry data that fail checks such as a CRC, an alive counter or an authentication value. AUTOSAR's end-to-end protection names the fault types behind this: repeated, lost, delayed, corrupted or masqueraded frames. GM uses the partner U026C on its object detection bus and lists it next to U0075, a bus-off code for a whole network. That split helps diagnosis: if the bus fails, a bus-off code and several lost-communication codes appear together; a lone U056D points to sensor H, its software or its own connector. Which camera is H is not public, and no brand documents U056D. Assistance that relies on it shuts off; no MIL.

Likely causes

Sensor H software computing counters or checksums incorrectly
Poor contact at sensor H connector while the rest of the bus is fine
Image processing sensor H internally faulty

Symptoms

  • Single assistance function unavailable while others work
  • U056D stored without bus-off or other lost-communication codes

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–1,400
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

image processing sensor h

Related codes

U026CU056CU056EU0075

References: autosar.org, static.nhtsa.gov.