Powertrain, generic

P0E4A Hybrid/EV Battery Pack Voltage Sense F Circuit Range/Performance

Check engine lightOn

EmissionsRelevant

Drive cycleNot required

Limp modePossible

P0E4A reports that pack voltage measurement F lies within its electrical range but disagrees with a reference value. No manufacturer documents P0E4A publicly. GM's 2019 hybrid tables show two plausibility checks such a channel could face: P0ABB fails when pack voltage and the summed cell voltages differ by more than 12 V in 20 of 25 samples at 25 ms, and P0AF8 compares the pack sensor with the inverter bus voltage, failing at more than 13.95 V difference in 400 of 500 samples, or at more than 14.95 V against the charger bus. Both are Type A, so the MIL comes on in the first trip. CARB requires rationality monitoring of battery voltage sensors. The electrical faults of channel F are P0E49, P0E4B and P0E4C; channel E uses P0E45.

Likely causes

Contact resistance at a sense terminal distorting the channel F value

Fault in the comparison value, such as the inverter bus or cell voltage measurement

Measuring drift or software issue in the battery controller

Symptoms

MIL on in the first trip with reduced battery power
Implausible state of charge display

Repair estimate

DifficultyShop_onlyWorkshop job

Parts and labour€100–2,500

Time1–6 h

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

Parts involved

hv battery pack voltage sense fwiring harnessbms

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