Powertrain, generic (extended)

P208D Reductant Pump A Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P208D means the drive of DEF pump A reads high, typically a wire touching battery positive, so the controller has lost authority over the pump. Unlike the open and low faults, Ford checks this one with the driver switched on: on 2023 diesels pump voltage over 16 V or pump controller current above 5 A sets it, confirmed in only 2 s. GM's 2018 diesel table relies on a phase-shorted-to-battery message from the DEF module, 20 of 25 samples, Type A, while the 2014 table watches for high voltage on the active driver. Volkswagen's 2014 Touareg TDI uses a control current above 4.00 A, and Deutz EMR5 files it as P208D-12. For 2013–2014 Ram 2500 and 3500 with the 6.7L Cummins, bulletin 18-010-14 reflashes the doser control unit when the MIL comes on with P208D or P202E. Check for wires pinched against powered cables and wet connectors.

Likely causes

Pump drive wire shorted to a battery feed
Doser control unit software (Ram 6.7L, 18-010-14)
Moisture or corrosion in the pump connector
Internal fault in pump or pump controller

Symptoms

  • MIL and DEF system warning
  • No DEF dosing, rising NOx
  • Countdown to speed limit or no-restart

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–1,800
Time0.5–4 h

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

Parts involved

reductant pump

Related codes

P208AP208BP208CP20FDP2064P05F0

References: fordservicecontent.com, gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov.