Powertrain, generic (extended)

P2D6D Battery Charging System Positive Contactor D Control Circuit Range/Performance

Check engine lightUsually off

EmissionsNot relevant

Drive cycleNot required

Limp modeNo

P2D6D points to a coil circuit of positive charging contactor D that works but behaves implausibly: current or voltage on the line drifts out of its normal window although no open or short is present. No manufacturer documents P2D6D publicly, and GM's published tables contain no such range test for charge contactors. A GM patent explains what the coil current can reveal: the position of the armature shapes the current response, so a contactor that is fully or partly closed draws a recognisably different curve, judged by its derivative and integral against a stored reference. CARB expects monitored hybrid outputs to answer commands properly. Contact resistance and a sluggish armature fit this code. P2D6C, P2D6E and P2D6F cover open, low and high.

Likely causes

Raised contact resistance in the coil circuit

Sluggish or partly jammed armature in contactor D

Ageing output stage delivering too little current

Symptoms

Charging via contactor D interrupted sporadically
Contactor pulls in late or chatters
Code returns after clearing

Repair estimate

DifficultyShop_onlyWorkshop job

Parts and labour€100–1,500

Time1–5 h

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

Parts involved

bcs pos contactor dwiring harnessbms

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