Battery Temperature Sensor Circuit
What it means
P0515 means the ECM has detected a problem in the battery temperature sensor circuit. This sensor lets the charging system adjust its voltage to the battery's temperature so it charges correctly in hot and cold conditions. It's usually a bad sensor or a wiring/connector fault. The car still starts and drives, but without accurate battery temperature the charging voltage can drift, so it's worth repairing.
Can I keep driving? Yes — the car starts and drives normally. The main risk is the charging system over- or under-charging the battery over time, so fix it before it shortens battery life.
Common symptoms
What you'll notice
- Check-engine light on
- Often no noticeable driving symptoms
- Over- or under-charging (battery gassing, or slow to charge)
- Shortened battery life over time
Common causes
Most likely first
- Faulty battery temperature sensorLikely
- Corroded or damaged wiring/connector in the sensor circuitCommon
- Sensor circuit shorted to ground or openCommon
- ECM fault (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check the sensor's reading with a scan tool against ambient temperature.
- Locate the battery temperature sensor (often under or near the battery tray) and inspect its connector and wiring.
- Test the sensor circuit for shorts to ground or opens.
- Compare the sensor's resistance to spec and replace it if faulty.
- Repair the wiring or replace the sensor, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0515?+
Can I just clear P0515?+
Related codes
Often seen with P0515
Read & clear P0515 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.