What does code P1421 mean on BMW vehicles?
The ECU detects a malfunction in the secondary air injection system on Bank 1.
OBD-II Code BMW
P1421 — BMW — Secondary Air System Bank 1
The ECU detects a malfunction in the secondary air injection system on Bank 1.
Common symptoms
- Increased emissions
- check engine light
Possible causes
- Faulty secondary air pump
- valves
- or hoses
Initial recommendation
Inspect secondary air pump, valves, and hoses for Bank 1.
Safety notice
This information is for guidance only. Brand-specific codes may vary by model, year, engine, transmission and vehicle configuration. It does not replace a physical inspection or diagnosis by a qualified mechanic. If the vehicle is unsafe to operate, avoid driving it and seek professional inspection.
Analyze this code with MecaOBD
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