P00B4Radiator Coolant Temperature Sensor Circuit High
Radiator coolant temperature sensor signal voltage above expected range. The engine coolant temperature sensor feeds warm-up enrichment, fan control and closed-loop entry — a stuck-cold reading keeps the engine in open loop and rich forever.
Can I keep driving? With caution
You can drive to the shop, but do not postpone the repair. The problem may worsen and damage other components.
Sistema Afectado
Aire / Combustible · Inyección, MAF, MAP, O₂

Relacionado con la mezcla aire-combustible: sensores de flujo, presión, inyectores o bomba.
Espacio para vendedores de repuestos
Aún no hay un anunciante en este espacio.
Possible Causes
The components or conditions that trigger this code
- 1Signal wire open Connector pins corroded - high contact resistance Supply wire pinched against B+ source
How to Fix It — Step by Step
Recommended diagnostic and repair procedure
- 1Difficulty: easy. Estimated time: 0.3-1.5 hours. Estimated cost: €40-€
- 2DIY possible
Note: This information is for general reference. For precise diagnostics and safety repairs, always consult a certified mechanic.
Estimated Cost
Approximate range in USD (varies by region and shop)
Varies by diagnosis
* Diagnosis only: $50–$150
Quick Info
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