Powertrain, generic · Hybrid propulsion

P0B6D Hybrid/EV Battery Voltage Sense K Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0B6D marks an open circuit on voltage sense K, the eleventh cell measuring channel. GM has used the code since its first published hybrid tables: in 2011 the open-line test already checked bus bar voltages, flagging more than 0.7 V. The 2019 battery energy control module refines it into seven cases, among them adjacent cells 1.3 V apart, a cell under 36 mV with balancing active and splice voltages over 0.1 V, all judged in a 0.6 s window and set as Type A. Ford counts P0B6D among the open sense line codes that leave a 2019-2020 Fusion plug-in hybrid unable to start and fixes it by replacing the traction battery. Before any pack work, the high-voltage system has to be disabled by trained staff.

Likely causes

Loose or corroded bus bar connection at the channel K tap
Internal traction battery fault, pack replacement (Ford Fusion PHEV)
Broken sense wire between cells and monitoring board

Symptoms

  • Vehicle not ready to drive
  • Hybrid or EV system warning with MIL
  • Charging not possible

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€80–8,000
Time0.5–8 h

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

Parts involved

hv battery voltage sense kwiring harnessbms

Related codes

P0B6EP0B6FP0B70P0B71P0B68P0B72

References: gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov, law.cornell.edu.