P0AFA: Hybrid/EV Battery System Voltage Low

P0AFA protects the traction battery from deep discharge: the pack voltage, or in some versions any cell voltage, has fallen below a temperature-dependent limit. GM's 2016 and 2019 tables set it after 320 of 400 samples (about 10 s) for the pack or 112 of 140 for a cell, Type A, and latch it so that only a technician command can clear it. GM bulletins name causes: degraded cell groups in 2011-15 Volt and ELR (19-NA-117), a blown fuse in the Bolt EV manual disconnect lever (18-NA-225), cell contamination in the 2015 Spark EV (17-NA-131) and repeated cranking that empties the Malibu Hybrid pack (PIC6229). A Ram eTorque parts notice names it for the 48 V power pack. Expect a no-start.

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

Vehicle does not start; restart blocked while the code is latched
Reduced or lost propulsion before the no-start
Plug-in charging not possible

Most likely causes

Degraded or self-discharging cell groups
Pack drained by repeated failed engine starts or long standing
Open high-voltage fuse or manual disconnect
Loose or high-resistance ground on 48 V systems

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
With the connector unplugged, check whether the signal wire is making contact with ground.
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

It can trigger limp mode.
It affects emissions.

What each character of P0AFA means

P: Powertrain: engine and transmission
0: Generic code: same on every make
A: Hybrid or air and fuel
FA: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0AFA?

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 P0AFA?

The most common causes are: degraded or self-discharging cell groups; pack drained by repeated failed engine starts or long standing; open high-voltage fuse or manual disconnect.

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.