Powertrain, generic (extended)

P2D5C Battery Charging System Positive Contactor C Stuck Closed

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

P2D5C is set when positive charging contactor C still conducts after the module commanded it to open; fused contacts are the usual reason. No manufacturer documents P2D5C publicly. Patents describe how a weld shows up: Ford opens its charge contactors one at a time after a session and treats one as welded if the voltage measured at the charger stays within a set margin of the battery voltage; one welded pole blocks further charging, both welded also block driving. GM spots a stuck contactor before start-up from the coil current of a short pulse that is too brief to close a healthy one. Because the plus pole of that charging path can stay live, the module usually locks the path. P2D5D is the reverse fault, P2D63 a welded minus contactor C, P2BC5 the contactor B twin.

Likely causes

Main contacts of contactor C welded, e.g. after switching under load
Coil output stage does not switch off
Faulty voltage measurement on the charger side simulating a weld

Symptoms

  • Charging blocked after the previous session
  • High-voltage warning, possibly no ready mode
  • Code appears at the end of a charging session or at start-up

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€200–4,000
Time1–10 h

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

Parts involved

bcs pos contactor cwiring harnessbms

Related codes

P2D5BP2D5DP2D63P2BC5P0D08

References: patents.google.com, patents.google.com, law.cornell.edu.