Powertrain, generic · Hybrid propulsion

P0B95 Hybrid/EV Battery Voltage Sense S Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0B95 reports that the sense S lead, channel nineteen, no longer connects its cell reliably to the monitoring electronics. GM programmes with a separate battery sensor module (16OBDG02) measure this directly: after each normal reading the balancing gates switch in a test pattern, current flows through the sense wires and the voltage drop is turned into a line resistance. Above 30.00 (the table gives no unit) in 7 of 9 samples at 100 ms, the code sets as Type A. GM's eAssist mild hybrid instead needs lines N and N-1 both under 1.4 V plus a jump of more than 0.5 V in 200 ms, 7 of 10 samples, Type B, and stays quiet while P1B37 is active. The 2019 lithium-ion controller uses its seven cases with 0.8 s in 1.6 s.

Likely causes

High resistance in sense lead S from corrosion or a loose terminal
Sense lead S broken at the cell connector
Defective input of the battery sensor module for channel S

Symptoms

  • MIL and hybrid or EV warning
  • Vehicle may refuse ready mode
  • Cell balancing no longer effective

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€150–6,500
Time1–10 h

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

Parts involved

hv battery voltage sense swiring harnessbms

Related codes

P0B96P0B97P0B98P0B99P0B90P0B9A

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