Network, generic

U045C Invalid Data Received From Power Steering Control Module B

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

Power steering module B is the second controller of a redundant electric steering system. Bosch presented a fail-operational EPS for highly automated driving in 2017: if one path fails, the system can still steer the car to a safe stop or spare the driver a sudden rise in steering effort. U045C is set when the partner, typically steering module A or the automation computer, gets messages from B but finds them invalid, for instance a frozen counter or a mismatching CRC under AUTOSAR end-to-end protection; complete silence from B is U015B, and invalid data from module A is U0420. No manufacturer documents U045C publicly. Assisted steering usually continues on path A, but a steering warning and blocked automated steering are likely until the cause is found.

Likely causes

Software or calibration of steering module B not matching module A
Voltage dips or poor ground at the second steering path
Internal fault of steering module B

Symptoms

  • Steering system warning
  • Lane centring or automated steering unavailable
  • Steering assist reduced in some cases

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€80–1,800
Time0.5–3 h

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

Parts involved

power steering module b

Related codes

U015BU0420U0131U045B

References: us.bosch-press.com, autosar.org.