P0A1E: Starter/Generator Control Module

Mild and full hybrids often start the engine and recharge the battery with a belt-driven starter-generator that has its own control electronics. P0A1E means that controller has reported a fault or works incorrectly. Audi stores P0A1E00 in the starter-generator control module of the 2020-2022 Q3 mild hybrid and cures it with a software update. Ford logs P0A1E in the engine control module of 2021-2023 F-150 PowerBoost and 2020-2026 Explorer and 2020-2023 Aviator hybrids; its bulletins name a loose connection at the belt integrated starter-generator or its software. Drivers notice a wrench or MIL lamp, no start-stop and no electric-only driving.

Symptoms

• Wrench lamp or MIL on, electrical system warning
• Auto start-stop disabled
• Electric-only driving unavailable

Most likely causes

• Loose wiring connection at the starter-generator
• Starter-generator software fault, fixed by update
• Starter-generator with integrated electronics failed

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. Make sure the battery cooling air intake is clean
3. Check the 12 V auxiliary battery, which can also trigger warnings
4. Leave any high-voltage measurements to a specialized repair shop

Good to know

• Repair difficulty: hard
• It affects emissions.

What each character of P0A1E means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• A: Hybrid or air and fuel
• 1E: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0A1E?

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 P0A1E?

The most common causes are: loose wiring connection at the starter-generator; starter-generator software fault, fixed by update; starter-generator with integrated electronics failed.

Related codes

• P0A1AGenerator Control Module
• P2D9BStarter/Generator Phase U Current Circuit Intermittent/Erratic
• P0A94DC/DC Converter A Performance

Sources

• static.nhtsa.gov: MC 10209449 0001
• static.nhtsa.gov: MC 10250306 0001
• static.nhtsa.gov: MC 11031640 0001

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.