Powertrain, generic · Hybrid propulsion

P0B7E Hybrid/EV Battery Voltage Sense N Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0B7E sets when channel N reads below the lower plausibility limit. GM's 2016 program with a separate battery sense module uses less than 0.20 V and needs 14 failures in 18 samples, about 1.8 s at 100 ms each, before a Type A fault; the open-circuit test must not be failing at the same time. The other GM lithium-ion controllers use 0.2 V or less for 1.4 s in 2 s, also Type A. The BAS Plus mild hybrid works with 1.4 V and 7 of 10 samples, Type B. On 2012 two-mode trucks N is NiMH block 14, and blocks 14 and 15 must both drop under 2 V. A low reading usually comes from the measuring path, not from the cell: a lead shorted to a lower potential or a damaged input stage.

Likely causes

Sense lead N shorted to a lower potential
Damaged input stage in the sense module
Deeply discharged or failed cell on channel N

Symptoms

  • MIL from the first trip on lithium-ion GM systems
  • Hybrid system limits power
  • Combustion engine does not shut off at standstill

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 nwiring harnessbms

Related codes

P0B7CP0B7DP0B7FP0B80P0B79P0B83

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