P1258 – Fuel Additive System Fault
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Symptoms
- Warning for additive
- DPF regeneration issues
- Check engine light
- Emissions failure
- Possible power loss
Causes
- Low additive level
- Faulty additive pump
- Level sensor fault
- Wiring issue
- Control module fault
Diagnosis
- Check additive level
- Inspect additive tank
- Check pump operation
- Inspect wiring
- Scan for related codes
Repair
- Refill additive
- Replace additive pump
- Replace level sensor
- Repair wiring
- Update ECU software