Code P0515 indicates the powertrain control module (PCM) has detected a malfunction in the battery temperature sensor circuit. This sensor measures battery temperature to optimize charging voltage and protect the battery; a circuit fault can lead to improper charging and reduced battery life.
The sensor, often integrated into the battery current sensor or battery management system, can fail internally, sending incorrect signals to the PCM.
Corrosion, loose terminals, or broken wires in the sensor circuit can cause high resistance or open/short circuits, triggering the code.
A weak, overcharged, or failing battery can produce abnormal temperature readings or voltage fluctuations that affect the sensor circuit.
The PCM may misinterpret sensor signals due to an internal fault, but this is uncommon and should only be considered after ruling out all other causes.
Yes, the vehicle is usually drivable, but the charging system may not work optimally, potentially leading to battery overcharge or undercharge. Prolonged driving without repair can shorten battery life.
Often, the battery temperature sensor is integrated into the battery current sensor or the battery management module. It may not be a separate standalone component.
Not necessarily. While a failing battery can contribute, the code usually points to a circuit or sensor issue. Diagnose the sensor and wiring before replacing the battery.
It is very rare. The PCM is often misdiagnosed for this code. Always rule out the sensor, wiring, and battery first, as PCM failure is the least likely cause.