OBD-II fault code

P0E36: DC/DC Converter Voltage Sensor B Circuit

What it means

The DC/DC converter voltage sensor B circuit has an electrical fault, so its reading may be unavailable or unreliable.

At a glance

  • Usually lights the check-engine light
  • The engine or gearbox may go into limp mode

How it works

The DC/DC converter changes high-voltage battery power into lower-voltage power for the vehicle's electrical system. The control module monitors voltage sensor B's circuit for a usable electrical signal and sets P0E36 when that circuit has a fault, making the reading unreliable or unavailable.

Common causes

Most likely first.

  1. Sensor failed
  2. Wiring or connector fault

Symptoms

  • Hybrid/EV system warning light may turn on
  • Reduced power or charging performance

How to diagnose it

  1. Record freeze-frame data and related converter codes, then compare sensor B's reported value with sensor A and other available voltage data.
  2. With the vehicle powered down as specified by the manufacturer, inspect sensor B's connector and harness for looseness, corrosion, pin damage, or chafing.
  3. Check the sensor B circuit's power, ground, and signal paths using the manufacturer's wiring diagram and specifications.
  4. If the wiring and connections are sound, test sensor B and its reference or ground circuit to distinguish a failed sensor from a circuit fault.
  5. After repair, clear the code and confirm sensor B reports plausibly during the manufacturer's prescribed converter checks.

Common fixes

  • Reseat and secure the DC/DC converter voltage sensor B connector.
  • Repair damaged wiring, terminals, or ground connections in sensor B's circuit.
  • Replace voltage sensor B if testing confirms it has failed.
  • Clear the code and verify sensor B's reading after the repair.

Can I keep driving?

The fault may reduce power or charging performance, so avoid long trips or situations where a loss of electrical support would be unsafe. If the vehicle shows a hybrid/EV warning or reduced power, stop in a safe place and arrange prompt diagnosis.

A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together

This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.

Codes for the same component