Powertrain, generic · Hybrid propulsion

P0BBB Hybrid/EV Battery Voltage Sense Z Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

If the Z channel shows a cell voltage above the upper limit, the controller sets P0BBB. The 2016 Volt battery module uses 4.8 V or more for 1.4 s in a 2 s window, Type A, and checks first that the cell monitoring slave is communicating and no open sense line is reported. The 16OBDG02 programme fails above 4.90 V in 14 of 18 samples, and the eAssist mild hybrid fails above 4.65 V in seven of ten samples with a healthy 12 V supply, Type B over two trips. Lithium-ion cells are not meant to exceed these values, so the reading normally points to a short towards the higher neighbour, a faulty input or a corrupted measurement, and only rarely to a truly overcharged cell. Charging is stopped as a precaution.

Likely causes

Sense lead Z shorted towards the higher neighbour cell
Faulty measuring input Z
Cell Z overcharged

Symptoms

  • MIL and charging stopped
  • Reduced regeneration

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–6,000
Time1–8 h

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

Parts involved

hv battery voltage sense zwiring harnessbms

Related codes

P0BB8P0BB9P0BBAP0BBCP0BB6P0ABD

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com.