Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC P065A
DTC P065A:Â ACG No Charging Malfunction
General DescriptionÂ
The alternator is driven by the engine, and it generates electricity according to the commands from the powertrain control module (PCM). The local interconnect network (LIN) line is connected to the alternator and transmits/receives information to/from the PCM. The voltage regulator in the alternator self-diagnoses itself, and by the PCM demands, the results are transmitted via the LIN line. If the self-diagnosed results are judged as generation unable or alternator rotation stop, the PCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type, OBD StatusÂ
| Execution | Continuous |
| Sequence | None |
| Duration | 5 seconds or more |
| DTC Type | One drive cycle, MIL off |
| OBD Status | PASSED/FAILED/NOT COMPLETED (STILL TESTING) |
Enable ConditionsÂ
| Condition | Minimum | Maximum |
|---|---|---|
| Engine speed [ENGINE SPEED] | 430 rpm | - |
| No active DTCs set (prevents monitor from running) | P16E2 | |
[ ]: HDS Parameter
Malfunction ThresholdÂ
Any of the conditions is met for at least 5 seconds:
- +B terminal voltage is regulated voltage or more, and F terminal voltage is HIGH.
- +B terminal voltage is 10 V or less (when the alternator speed is 3, 000 rpm or less), or 11 V or less (when the alternator speed is 3, 000 rpm or more).
- P terminal voltage is 2 V or less (when the alternator speed is 3, 000 rpm or less), or 6 V or less (when the alternator speed is 3, 000 rpm or more).
- Alternator speed is 400 rpm or less.
Possible CauseÂ
NOTE:Â The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Alternator internal failure (voltage regulator failure)
- Alternator rotation defection
Diagnosis DetailsÂ
Conditions for setting the DTCÂ
When a malfunction is detected, a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory. The MIL does not come on.
Conditions for clearing the DTCÂ
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.