P0E36: DC/DC Converter Voltage Sensor B Circuit

P0E36 is the catch-all circuit code for the second voltage measurement of a DC/DC converter, sensor B. Where a converter reads both its input and its output, or monitors one rail twice, the second path gets the letter B; FCA names it voltage sensor 2 on the 2021 Ram 1500 eTorque. No manufacturer documents P0E36 itself in public sources. GM's 2025 engine tables treat sensor B through its sibling codes only: below 1 V is P0E38, above 28 V is P0E39, and a gap of more than 2 V to the ECM run/crank voltage is P0E37. P0E36 is left for electrical faults that fit none of those, such as an open line the controller recognises as such. CARB asks for circuit faults of inputs to be detected separately where feasible. Converter output may be reduced.

High severity. Can I keep driving?If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

Symptoms

Warning light, possibly 12 V battery warning
Start-stop disabled or converter output reduced

Most likely causes

Open sense wire or unplugged connector
Second measuring path inside the converter failed
Poor ground of the converter

What to check, in order

Start with the simplest. You can tick off each step.

Read the codes with a hybrid-compatible scanner and write down the freeze frame data
Make sure the battery cooling air intake is clean
Check the 12 V auxiliary battery, which can also trigger warnings
Leave any high-voltage measurements to a specialized repair shop

Good to know

Repair difficulty: hard
It affects emissions.

What each character of P0E36 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
E: Subsystem depends on the code range
36: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0E36?

If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

What causes code P0E36?

The most common causes are: open sense wire or unplugged connector; second measuring path inside the converter failed; poor ground of the converter.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.