Battery Temperature Sensor Circuit Low
Your car's battery temperature sensor is sending a signal that's too low, like a thermometer stuck reading freezing when it's actually warm. The engine computer can't properly adjust charging and cold-start strategies without accurate battery temperature data.
The ECM monitors voltage from the battery temperature sensor (typically a thermistor) to adjust alternator output and fuel enrichment during cold starts. When sensor voltage is below the minimum threshold, the ECM interprets battery temperature as abnormally cold or detects a circuit fault.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Sensor Voltage | 0.5V - 4.5V (representing -40°C to 125°C) | Below 0.1V or open/short circuit detected |
| Temperature Reading | -40°C to 125°C | Signal indicates impossibly cold or disconnected sensor |
Code P0516 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0516 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.