BMW fault code 40BA

Diesel electronics slave

40BA Monitoring Master/Slave faultpath for CoVehtrqLimErr (BIT6 is set in status byte)

Module version: Diesel electronics slave (D63SM670)

Which BMWs have this version depends on the engine and equipment, so we don't list them here; AutoLingo for BMW reads which version your car has.

Reading and clearing it

Fault code 40BA is a BMW code, stored in the car's diesel electronics slave, 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 diesel electronics slave is on: 7 Series (E65), 7 Series (E66), 7 Series (E67)

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