BMW fault code AA28

Hybrid Interface Module

HIM: Transport mode active

Module version: Hybrid Interface Module (HIM_72)

In: X6 (E72) 2009–2011

Reading and clearing it

Fault code AA28 is a BMW code, stored in the car's hybrid interface module, not a generic OBD2 code (P0xxx): a generic OBD2 reader only reaches the engine's emissions faults, so it won't show it. AutoLingo for BMW reads it with BMW's own diagnostic protocols, in plain English, with the details the module stored about it, and clears it after a repair. If a fault comes right back after it's cleared, the problem is still there.

The hybrid interface module is on: X6 (E72)

All hybrid interface module fault codes AA29 →