48E0

48E0 - P321F

Information saved in
DDE

Fault code
48E0 - P321F

Fault text
Ambient pressure sensor (installed in DDE control unit),
plausibility: Ambient pressure too low (not plausible in rel.
to pressure before turbocharger and charge-air pressure)

Fault description
Under certain operating conditions (start, shutdown, specific
operating points) the pressures from ambient barometric
pressure sensor, exhaust-gas backpressure sensor and boost-
pressure sensor are checked for mutual plausibility. If the
ambient pressure is farther than -130 mbar from the other
two pressures and if their difference is less than 150 mbar
the ambient pressure sensor is registered as defective.

Condition for fault identification
Test condition:
The plausibility test runs when one of the valid operating
ranges is active:
Engine in standby mode: Status transition from wake-up for
at least 0 s.
Terminal 15 on:
- Terminal 15 on for at least 400 ms.
- Engine rpm lower than 0 1/min.
Engine in start phase:
- Engine rpm lies between 16384 1/min and 16384 1/min.
- Terminal 50 active.
During extended idling phase and with low particulate filter
content:
- Engine running.
- Operating range is valid for at least 200 ms.
- Engine speed lies between 10 1/min and 10 1/min.
- Injection quantity lies between 0 mg/Hub and 328 mg/Hub.
- Throttle valve value less than 100 %.
- Maximum value for particulate filter load quantity less
than 0 g.
- Period since last particulate filter regeneration greater than
200 s.
- Vehicle speed less than 10 km/h.
Engine is in shutdown phase for at least 2500 ms.
Voltage condition:
The plausibility test runs when one of the valid operating
ranges is active:
Engine in standby mode: Status transition from wake-up for
at least 0 s.
Terminal 15 on:
- Terminal 15 on for at least 400 ms.
- Engine rpm lower than 0 1/min.
Engine in start phase:
- Engine rpm lies between 16384 1/min and 16384 1/min.
- Terminal 50 active.
During extended idling phase and with low particulate filter
content:
- Engine running.
- Operating range is valid for at least 200 ms.
- Engine speed lies between 10 1/min and 10 1/min.
- Injection quantity lies between 0 mg/Hub and 328 mg/Hub.
- Throttle valve value less than 100 %.
- Maximum value for particulate filter load quantity less
than 0 g.
- Period since last particulate filter regeneration greater than
200 s.
- Vehicle speed less than 10 km/h.
Engine is in shutdown phase for at least 2500 ms.

Condition for fault memory entry
Debounce (500 ms)

Action in service
Replace DDE control module.

Fault effect and breakdown warning
Proceed to the nearest BMW Service facility.

Driver information
Warning light:
MIL

Service instruction
none