Powertrain, generic · Hybrid propulsion

P0B47 Hybrid/EV Battery Voltage Sense C Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0B47 is stored when channel C delivers a voltage too low to come from a working cell or block, so the controller blames the measurement rather than the battery. GM documents two implementations. On lithium-ion packs the battery energy control module sets it at 0.2 V or less for 1.4 s within 2 s, Type A, one trip, unless an open sense line, communication or balancing fault is already active. On the 2012 Tahoe, Yukon, Escalade, Silverado and Sierra two-mode hybrids channel C is nickel-metal hydride block 3; there block 3 and block 4 must both read under 2 V in 15 of 20 samples, Type B, two trips. Shorted sense lines or a failed measuring input are the usual suspects.

Likely causes

Sense lines of channel C shorted to each other or to a neighbouring tap
Failed measuring input in the battery monitoring module
Loose or corroded block connector shared by blocks 3 and 4 (GM two-mode)

Symptoms

  • Hybrid system warning and MIL
  • Electric drive or engine start-stop no longer available
  • Battery power limited, sluggish acceleration

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€50–5,000
Time0.3–6 h

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

Parts involved

hv battery voltage sense cwiring harnessbms

Related codes

P0B45P0B46P0B48P0B49P0B42P0B4CP0ABC

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