OBD-II DTC · SAE J2012

U028A

Lost Communication With Transmission Fluid Pump Module B

Transmission → Depends on cause

What U028A means

U028A is a standard SAE J2012 powertrain diagnostic trouble code with the defined meaning: Lost Communication With Transmission Fluid Pump Module B. This is the OEM-agnostic definition; specific manufacturer interpretation may add detail (subsystem, bank, sensor location) but the core meaning is consistent across all OBD-II compliant vehicles since 1996.

Common symptoms when U028A is active

Gearbox limp, harsh shifts, TCM communication MIL, ratio / solenoid / pressure DTCs.

Can this code be suppressed via ECU tuning?

Whether this code is safe to suppress depends on the underlying cause. Diagnose first, suppress only after confirming the mechanical issue is benign or rectified.

How to remove U028A with Softechpro V5

Recommended service: DTC OFF (TCM) — limited use. Step-by-step workflow:

  1. Transmission DTCs usually require the actual TCM dump, not the engine ECU. Confirm the code is on the TCM side.
  2. Softechpro V5 supports DTC OFF on common TCM platforms (DSG, ZF, Mercedes 722.6 / 722.9, GM 6L80, BMW ZF8HP).
  3. Load TCM .bin, select DTC OFF + transmission DTC group, save, flash.

Softechpro V5 supports 1,400+ ECU firmwares across Bosch (EDC15, EDC16, EDC17, MD1, MG1, ME7, MED17), Siemens / Continental (SID, SIMOS, EMS), Delphi (DCM, DDC), and Magneti Marelli platforms.

Related codes in the U02xx family

U0200U0201U0202U0203U0204U0205U0206U0207U0208U0209U020AU020B