What does code U04B3 mean?

DTC codes / U04xx · Invalid data received from a module / U04B3

U04B3Invalid Data Received From Planetary Gear Set Control Module

This code means the transmission control module (TCM) or another onboard computer expected to receive valid data from the planetary gear set control module and instead received a message flagged as invalid or corrupted. The planetary gear set control module is the electronics that monitor and control the clutches and brakes inside the automatic transmission's planetary gear set, so the fault is a communication or data integrity problem rather than a direct mechanical failure.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaInvalid data received from a module

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.