P2D59 code meaning
Generator B Over Temperature
What P2D59 means
P2D59 indicates that generator B has become too hot. Which machine B means is up to the manufacturer: a second alternator in a dual charging system or a second motor-generator in a hybrid. No manufacturer documents P2D59 publicly. For generator A, Mitsubishi describes the hybrid case under P0A3B on the 2023 Outlander PHEV: a W-phase coil temperature of 199 °C or more for one second sets the code. On the alternator side, Infineon's LIN regulator TLE8881-3 raises a high-temperature flag as soon as the chip passes a programmable compensation threshold, where it also starts lowering the voltage set point. Typical causes are blocked cooling air or oil flow, sustained overload, a failed fan or a misreading sensor. Output is cut back, so charging or hybrid power may be limited.
P2D59 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 6 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2D59
- Reduced charging output or charge warning
- On hybrids, limited electric or series-mode power
Common causes of P2D59
- Most likelyObstructed cooling air path or reduced oil/coolant flow to the generator
- PossibleSustained high electrical load at low engine speed
- Less likelyTemperature sensor or regulator measuring wrongly
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Generator bVoltage regulator
What each part of P2D59 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 59 | The exact fault in that area. |
What to do next
- Note P2D59 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 P2D59
What does P2D59 mean?
P2D59 means "Generator B Over Temperature". P2D59 indicates that generator B has become too hot. It is a generic code, so it means the same on every make.
Is it safe to drive with P2D59?
Drive gently and only to a workshop. With P2D59 the car can go into limp mode (reduced power) to protect itself.
Will P2D59 fail an emissions test?
P2D59 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P2D59 to fix?
Difficulty: hard. A typical repair takes 1 to 6 hours of work. This is a job for a workshop.
Will P2D59 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.