Powertrain, generic · Hybrid propulsion

P0BB7 Hybrid/EV Battery Voltage Sense Y Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0BB7 would describe an unstable sense Y signal, one that is mostly correct but drops out or jumps from time to time. No manufacturer publishes a monitor for it. Where GM covers channel Y, in the 16OBDG02 programme and the 2019 battery and hybrid processor tables, it does so with P0BB3 to P0BB6: line resistance, trend comparison, low and high limits. A brief interruption would there show up as a counted failure inside one of those tests rather than under its own code. P0BB7 thus exists as a J2012 placeholder that satisfies the CARB 1968.2 demand for monitored battery voltage sensors. Diagnosis would focus on connectors, crimps and solder joints that react to movement or heat.

Likely causes

Intermittent contact in the Y sense connector
Crimp or weld on lead Y opening when hot
Hairline crack in a solder joint of input Y

Symptoms

  • Warning lamp appears now and then
  • Short-lived power limitation

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€80–5,000
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

P0BB3P0BB4P0BB5P0BB6P0BB2P0BBC

References: law.cornell.edu, gsi.ext.gm.com, gsi.ext.gm.com.