Powertrain, generic · Hybrid propulsion

P0B46 Hybrid/EV Battery Voltage Sense C Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

With P0B46 the channel C wiring is intact; the value on it looks plausible but no longer behaves like a real cell. GM's 2019 tables run the test in Hybrid Powertrain Control Processor 2: whenever the average cell voltage trends by at least 0.005 V in one direction, channel C has to follow; if it stays frozen in 35 of 40 samples at 100 ms, the code sets, Type A. The 2016 Chevrolet Volt uses a window of 7 out of 8 seconds instead. Chrysler calls the code Voltage Sense 3 Circuit Performance on the 2020 Pacifica plug-in hybrid and cures it by reflashing the battery pack control module. So before opening the battery, check the controller software level.

Likely causes

Battery controller software misjudging the channel, fixed by reflash (Chrysler Pacifica PHEV)
Measuring chip input for channel C stuck at a constant value
High-resistance cell tap damping the channel C signal

Symptoms

  • MIL on without noticeable driving fault
  • Reduced electric power or hybrid assist
  • Contactor or precharge codes stored at the same time (Pacifica)

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€50–6,000
Time0.2–8 h

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

Parts involved

hv battery voltage sense cwiring harnessbms

Related codes

P0B45P0B47P0B48P0B49P0B41P0B4B

References: gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov, law.cornell.edu.