Powertrain, generic · Hybrid propulsion

P0BAE Hybrid/EV Battery Voltage Sense X Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Channel X, number twenty-four, starts with P0BAE, the open-lead code. The first-generation Volt of 2011 already detected it through several cases: two neighbouring readings more than 1 V apart, a busbar sense voltage above 0.7 V combined with an implausible cell voltage, or adjacent cells differing by more than 0.5 V on a shared supply line. GM's later 16OBDG02 programme measures the sense line resistance directly and fails it above 30.00 in seven of nine samples, Type A; the unit is not printed. In the 2019 battery energy control module the familiar 1.3 V and 36 mV criteria apply with 0.8 s in 1.6 s. Whichever method is used, the controller loses sight of one cell and normally restricts the battery.

Likely causes

Sense lead X broken or disconnected
Loose busbar fastener at the X sensing point
Sense harness X damaged during earlier battery work

Symptoms

  • MIL and service message for the high-voltage system
  • Vehicle may stay out of ready mode
  • Charging stops early

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€150–7,000
Time1–10 h

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

Parts involved

hv battery voltage sense xwiring harnessbms

Related codes

P0BAFP0BB0P0BB1P0BB2P0BA9P0BB3

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