P0A7A: Generator Inverter Performance

P0A7A reports that the inverter stage driving the generator has signalled a fault, for example overcurrent or a failed power switch. Toyota uses the code across its hybrids and splits it with information codes. Bulletin T-SB-0142-16 covers 2012-2016 Avalon, Camry and RAV4 Hybrid with MIL on and P0A7A plus information code 122, a generator inverter fail signal caused by overcurrent; the repair replaces inverter and transaxle. A Toyota field report filed with NHTSA describes a 2006 Highlander Hybrid with P0A7A sub code 325, master warning, MIL and Check Hybrid System, traced to a fault inside the inverter assembly. P0A78 and P0A79 are the drive motor inverters, P0A3E generator inverter overheating, P0A92 generator performance.

Symptoms

• MIL, master warning and Check Hybrid System message
• Reduced power or vehicle will not enter ready mode

Most likely causes

• Internal generator inverter fault with overcurrent (Toyota information code 122)
• Inverter assembly defective
• Fault in the generator inside the transaxle
• Insufficient inverter cooling stressing the power stage

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. Compare the reading with other engine data while varying the engine speed.
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

• It can trigger limp mode.
• It affects emissions.

What each character of P0A7A means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• A: Hybrid or air and fuel
• 7A: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0A7A?

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 P0A7A?

The most common causes are: internal generator inverter fault with overcurrent (Toyota information code 122); inverter assembly defective; fault in the generator inside the transaxle.

Related codes

• P0A78Drive Motor A Inverter Performance
• P0A79Drive Motor B Inverter Performance
• P0A3EGenerator Inverter Over Temperature
• P0A92Hybrid Generator Performance
• P0A4BGenerator Position Sensor Circuit

Sources

• static.nhtsa.gov: MC 10161538 9999
• static.nhtsa.gov: INRD PE11005 45763P

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.