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P2B20

Hybrid/EV Electronics Coolant Temperature Sensor B Circuit

The vehicle hybrid control module detects a circuit fault on the coolant temperature sensor B that monitors the power electronics cooling loop.

  • Check engine light: Yes
  • Emissions related: No
  • Repair difficulty: medium

Common causes

Ordered by how often each turns out to be the cause.

  • Sensor failedCommon
  • Wiring or connector faultPossible

Parts involved

  • Hybrid Electronics Coolant Temp Sensor B
  • Wiring Harness
  • Hybrid Control Module

P2B20 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.