Powertrain, generic (extended)

P2ACD Reductant Temperature Sensor B Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2ACD flags a reductant temperature sensor B reading that is electrically fine but disagrees with the other temperatures the SCR controller knows, typically checked after a cold soak, when DEF lines, tank and ambient should read about the same. No manufacturer publicly describes P2ACD. The sensor A counterpart shows the pattern: Deutz files P2043-64 as a plausibility error of the DEF temperature input, and Ford bulletin 18-2190 for the 2011–2015 6.7L Super Duty treats P2043 alone as a software case (PCM reprogram) and calls for a new heater and sender unit only when P205C or P205D appear as well. A B-side plausibility code without circuit codes therefore deserves a software check before parts are ordered. P2ACC, P2ACE and P2ACF cover the electrical faults.

Likely causes

Controller software with an overly tight plausibility check
Sensor B drifting from its characteristic
Line heater warming the sensor area during the check

Symptoms

  • Check engine light after a cold start
  • SCR warning with no noticeable driving change

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–900
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

reductant temperature sensor breductant control module

Related codes

P2ACCP2ACEP2ACFP2AD0P2043

References: serdia.deutz.com, static.nhtsa.gov, law.cornell.edu.