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U0333 Software Incompatibility With Gear Shift Control Module B

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

With shift-by-wire, both the driver's selector and the unit that actually moves the range are electronic modules; module B denotes a second such unit, either a further selector or the shift actuator. U0333 means its software or calibration does not fit the partner controller. Allison lists it for the sixth-generation controls of its 3000 and 4000 series, released in 2021, as Gear Shift Module 2 Incompatible, next to U0304 for module 1; the same bulletin warns that new push-button selectors do not work with fifth-generation TCMs and that the fitted selector must match the TCM calibration (SIL 14-TR-21). Lexus labels the shift actuator ECU of the 2022 NX 350 and NX 250 with B and reflashed its main and sub calibration in campaign 22LC03. U0291 is lost contact, U0592 invalid data.

Likely causes

Selector or actuator of another generation or part number fitted
Transmission calibration specifies a different selector than the one fitted
Shift actuator ECU still on an outdated calibration

Symptoms

  • Range changes requested at this unit are ignored
  • Transmission warning or shift indicator fault
  • Vehicle stays in or returns to neutral or park

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–1,200
Time0.5–3 h

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

Parts involved

gear shift module b

Related codes

U0291U0592U0304

References: static.nhtsa.gov, static.nhtsa.gov.