B0403low severityBody
Fuel Gauge Circuit Malfunction
on 2003 BMW 525iT E39 2.5L I6 M54 Touring · RWD
What this code means
The fuel gauge is not displaying correctly or is stuck at one position.
Symptoms
- Fuel gauge stuck on empty
- Fuel gauge stuck on full
- Fuel gauge reads erratically
- Low fuel warning inaccurate
Common causes
- Faulty fuel level sending unit
- Instrument cluster gauge failure
- Wiring damage between tank and cluster
- Corroded fuel sender connector
- Float stuck in tank
Diagnostic steps
- Check fuel sender resistance with scan tool
- Test gauge with simulated sender resistance
- Inspect fuel sender connector
- Test gauge stepper motor
- Check ground circuit
Repair notes
Replace fuel level sending unit in tank or instrument cluster gauge. Check sender connector for corrosion.
Other Body codes on this vehicle
B0001
Driver Frontal Stage 1 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0005
Driver Knee Airbag Deployment Circuit
B0006
Passenger Knee Airbag Deployment Circuit
B0010
Driver Side Airbag Deployment
B0011
Driver Side Airbag Deployment Circuit Open
B0012
Driver Side Airbag Deployment Circuit Short to Ground
B0013
Driver Side Airbag Deployment Circuit Short to Battery