P0E65: Battery Charger Control Circuit/Open

P0E65 flags a fault on the wired command line through which the hybrid control unit operates the on-board charger, most often an interrupted line. GM uses it codegenau: in the 2016 Volt the VICM runs the test, in the 2019 hybrid tables (19OBDG01) the HPC2 module. The check relies on a fault flag raised by the output driver hardware itself and only runs while system voltage is 10.2 V or higher and the charger enable mask is active. Samples are taken every 25 ms; 30 bad ones among 40 store the code. GM classes it Type B, so the MIL comes on once the fault returns on a second trip. Low, high and plausibility faults on the same line have their own codes, P0E66 to P0E68. Plug-in charging is usually refused until the line is repaired.

Symptoms

• Vehicle does not charge when plugged in
• MIL after the second trip with the fault (GM)
• Charging fault message in the instrument cluster

Most likely causes

• Broken or disconnected charger control wire
• Corroded or pushed-out terminal at charger or control unit
• Defective output driver in the commanding control unit

What to check, in order

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

1. Read the codes with a hybrid-compatible scanner and write down the freeze frame data
2. Check the continuity of the wire between the component and the control module.
3. Make sure the battery cooling air intake is clean
4. Check the 12 V auxiliary battery, which can also trigger warnings
5. Leave any high-voltage measurements to a specialized repair shop

Good to know

• Repair difficulty: medium

What each character of P0E65 means

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

Frequently asked questions

Can I keep driving with code P0E65?

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 P0E65?

The most common causes are: broken or disconnected charger control wire; corroded or pushed-out terminal at charger or control unit; defective output driver in the commanding control unit.

Related codes

• P0E66Battery Charger Control Circuit Low
• P0E67Battery Charger Control Circuit High
• P0E68Battery Charger Control Circuit Range/Performance
• P0E61Battery Charger A Enable Circuit/Open

Sources

• gsi.ext.gm.com: 19OBDG01 Hybrid Diagnostics
• gsi.ext.gm.com: 16OBDG01 Hybrid Diagnostics
• law.cornell.edu: 13 CCR 1968.2

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.