P0A79 code meaning
Drive Motor B Inverter Performance
Powertrain system Generic code P0Axx codes Check engine light
What P0A79 means
P0A79 is the drive motor B counterpart of P0A78: the inverter stage for motor B has detected a power-switch fault. In GM hybrid OBD tables the IGBT module reports a desaturation status on a high or low side switch of any phase; persisting for about 2 ms it sets P0A79 as Type A with MIL on the first trip. Stellantis documents P0A79 several times: on the 2021 Jeep Wrangler 4xe together with P0A78 and an engine-only limp mode, fixed by a new power inverter module; on the 2017 Pacifica Hybrid with improved hybrid control software, and with a loose high-voltage cable at the inverter terminal that also caused loss of propulsion. P0A78 is motor A, P0A7A the generator inverter, P0A3D overheating of inverter B. The driver loses electric drive.
P0A79 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 6 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0A79
- MIL and hybrid system warning
- No electric drive, engine-only operation
- Loss of propulsion in severe cases
Common causes of P0A79
- Most likelyIGBT desaturation or short in the motor B power stage
- Most likelyPower inverter module defective
- PossibleLoose high-voltage cable at the inverter terminal (Pacifica Hybrid)
- PossibleHybrid control software requiring update
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Drive motor b inverterHybrid control module
What each part of P0A79 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| A | Area: hybrid propulsion. |
| 79 | The exact fault in that area. |
What to do next
- Note P0A79 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0A79
What does P0A79 mean?
P0A79 means "Drive Motor B Inverter Performance". P0A79 is the drive motor B counterpart of P0A78: the inverter stage for motor B has detected a power-switch fault. It is a generic code, so it means the same on every make.
Is it safe to drive with P0A79?
Drive gently and only to a workshop. With P0A79 the car can go into limp mode (reduced power) to protect itself.
Will P0A79 fail an emissions test?
Yes, it can. P0A79 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0A79 to fix?
Difficulty: workshop only. A typical repair takes 1 to 6 hours of work. This is a job for a workshop.
Will P0A79 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.