Powertrain, generic · Hybrid propulsion

P0BBA Hybrid/EV Battery Voltage Sense Z Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0BBA is stored when the voltage measured on channel Z falls below the lower limit. In the 16OBDG02 programme the hybrid processor checks Z every 100 ms and fails it below 0.20 V in 14 of 18 samples, a Type A fault, but only with a system voltage above 10.20 V and no open-circuit fault on the cell. GM's 2019 battery energy control module and the 2011 Volt use 0.2 V or less over 1.4 s within 2 s. This rules out a simple open lead, which would have set P0BB8 first. What remains is a short in the Z wiring or connector, a failed channel on the monitoring board or a cell whose voltage has actually collapsed. The battery is normally limited to protect the other cells.

Likely causes

Short in the Z sense wiring or connector
Failed channel Z on the monitoring board
Voltage collapse of cell Z

Symptoms

  • MIL and hybrid or EV warning
  • Limited power and charging

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

P0BB8P0BB9P0BBBP0BBCP0BB5P0ABC

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