Powertrain, generic

P0E3A DC/DC Converter Voltage Sensor B Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P0E3A covers an unsteady signal from voltage sensor B of a DC/DC converter: short spikes, dropouts or noise that never last long enough for the hard low or high codes. Publicly, no manufacturer documents P0E3A. For orientation, GM's 2025 engine tables (25OBDG03A) accept 1 to 28 V on raw voltage value 2 and only set P0E38 or P0E39 after roughly four seconds out of five of continuous failure, so brief disturbances slip past those tests. FCA calls this channel voltage sensor 2 on the Ram 1500 eTorque. CARB wants inputs checked for circuit, range and rationality faults; an erratic code is the gap filler. A fault confined to sensor B while sensor A is steady narrows the search to the B wiring and its terminals, often in a spot that moves with the engine.

Likely causes

Harness rubbing intermittently where it moves with the engine
Poor terminal tension in the sensor B circuit
Electrical interference on an unshielded sense line

Symptoms

  • Sporadic warning light, sometimes cleared on its own
  • Start-stop unavailable from time to time

Repair estimate

DifficultyHardWorkshop job
Parts and labour€50–1,500
Time0.5–3 h

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

Parts involved

dcdc voltage sensor bwiring harnessdcdc converter

Related codes

P0E35P0E36P0E37P0E38P0E39

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