BMW fault code 4521
Engine electronics
In the engine electronics, code 4521 means different things depending on the version of the module in the car. Find your car below; the app shows the right one for yours.
DDE: Charge-air pressure control, control deviation
Module versions: Digital Diesel Electronics (D50M47B1), Digital Diesel Electronics (D50M57D0), Digital Diesel Electronics (D50M57E0), Digital Diesel Electronics (D60M47A0), Digital Diesel Electronics (D60M57A0), Digital Diesel Electronics (D60PSA0), Diesel fuel electronics (D60TMCA), Digital Diesel Electronics (D62M57A0), Digital Diesel Electronics (D62M57B0), Diesel electronics master (D63MM670), Digital Diesel Electronics (D70N47A0), DDE (d70n47b0) (D70N47B0), Digital Diesel Electronics (D71N47A0), Digital Diesel Electronics (D71N47B0), Digital Diesel Electronics (D71N47C0), DDE (d71n47d0) (D71N47D0), DDE (d73n57b0) (D73N57B0)
Which BMWs have these versions depends on the engine and equipment, so we don't list them here; AutoLingo for BMW reads which version your car has.
DDE: Charge-air pressure control
Module versions: Digital Diesel Electronics (D50M47A), Digital Diesel Electronics (D50M57A0), Digital Diesel Electronics (D50M57A1), Digital Diesel Electronics (D50M57B1), Digital Diesel Electronics (D50M57C0), Digital Diesel Electronics (D50M57E1), Diesel electronics master (D51MM670)
In: 3 Series (E46) 1998–2006, X3 (E83) 2003–2010, X5 (E53) 1999–2006
4521 Charging pressure control, control deviation
Module versions: Digital Diesel Electronics (D72N47B0), Digital Diesel Electronics (D73N47A0)
Which BMWs have these versions depends on the engine and equipment, so we don't list them here; AutoLingo for BMW reads which version your car has.
Charge pressure control, control deviation
Module version: Digital Diesel Electronics (D60M57D0)
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.
Charging pressure control, high-pressure stage, control deviation: Charging pressure too high/negative control deviation
Module version: DDE US-diesel fuel (D73N57C0)
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.
4521 Charging pressure control, high-pressure stage, control deviation: Charging pressure too high/negative control deviation
Module version: Digital Diesel Electronics (D73N57D0)
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.
DDE: Charge-air pressure control (boost pressure control negative)
Module version: Digital Diesel Electronics (DDE50K47)
In: 3 Series (E46) 1998–2006, X5 (E53) 1999–2006, Z8 (E52) 2000–2003
Reading and clearing it
Fault code 4521 is a BMW code, stored in the car's engine electronics, 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 engine electronics is on: 3 Series (E46), Z8 (E52), X5 (E53), 5 Series (E60), 5 Series (E61), 6 Series (E63), 6 Series (E64), 7 Series (E65), 7 Series (E66), 7 Series (E67), X5 (E70), X6 (E71), X6 (E72), 1 Series (E81), 1 Series (E82), X3 (E83), X1 (E84), Z4 (E85), Z4 (E86), 1 Series (E87), 1 Series (E88), Z4 (E89), 3 Series (E90), 3 Series (E91), 3 Series (E92), 3 Series (E93)
Coming soon
Enter your email address to hear when AutoLingo for BMW is ready.