Powertrain, generic · Hybrid propulsion

P0BB6 Hybrid/EV Battery Voltage Sense Y Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

The battery controller logs P0BB6 when the Y channel climbs above a level no healthy cell reaches. GM's first Volt of 2011 put that limit at 4.8 V or more, 1.4 s within 2 s, with the MIL after one trip. The 16OBDG02 programme samples every 100 ms and fails above 4.90 V in 14 of 18 samples, Type A; the eAssist battery fails above 4.65 V in seven of ten samples at 200 ms, Type B. A wiring fault that connects the Y input to the potential of the next cell is the most common explanation, followed by a failed input. Overcharging of a single cell is possible after a balancing problem and must be ruled out before the pack is charged again.

Likely causes

Sense input Y bridged to the next cell potential
Defective input Y on the monitoring board
Overcharged cell Y after a balancing problem

Symptoms

  • MIL and charging stopped
  • Regeneration disabled

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 ywiring harnessbms

Related codes

P0BB3P0BB4P0BB5P0BB7P0BB1P0BBB

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