OBD-II code · Powertrain (generic, extended)

P2ADC Reductant Tank Temperature Sensor B Circuit High

Voltage on the reductant tank B temperature sensor signal line is above the expected window. Wire shorted to B+ or sensor open.

Is it safe to drive with P2ADC?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelySignal wire shorted to B+
  • PossibleOpen sensor
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • Check engine light or NOx warning on
  • AdBlue/DEF level or quality warning
  • Possible no-start countdown after ignore period
  • Failed emissions inspection (NOx)

Repair at a glance

Difficulty
Easy
DIY friendly
Often, with basic tools
Typical labour
0.3–1.5 h
Emissions test
Likely to fail
Parts involved
Reductant Tank Temperature Sensor B, Wiring Harness, Scr Module

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.