What Suzuki codes (P0420) actually mean on Suzuki engines — the real cause, the common misdiagnosis, and the honest UK repair cost.
These are the OBD fault codes we see most often on Suzuki vehicles in the workshop, with the real cause on Suzuki engines rather than the generic textbook definition, plus the honest independent-garage cost.
Suzuki fault codes explained
- P0420 — Catalyst efficiency on Suzuki — Swift/Vitara K12/K14 petrol cat ageing and rear O2 degradation. Typical UK cost £150–£750.
Codes are generic across manufacturers, but the fix is not. The same code on a Suzuki usually points at a different component than it would on another make, which is why a make-specific diagnosis saves money before any parts are bought.