What it means
Same as P0515 with the signal voltage below the plausible range. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
How it works
The battery temperature sensor circuit carries a signal used by the charging system to account for battery temperature. P0516 sets when the module detects that this signal is below its plausible range, commonly because it is shorted to ground or the connection has excessive resistance.
Common causes
Most likely first.
- Signal shorted to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
Symptoms
- Check-engine or charging-system warning light on
- Battery may be undercharged or overcharged
- Unusual charging voltage or battery drain
How to diagnose it
- Check freeze-frame data and live battery temperature to confirm that the low circuit reading is present when P0516 sets.
- Inspect the sensor connector and harness for moisture, corrosion, pushed-back pins, or chafing that could pull the signal low.
- With the sensor connected and disconnected as directed by service information, compare signal behavior with the manufacturer's specification to distinguish a sensor fault from a wiring fault.
- Test the signal wire for a short to ground and check connector terminal contact and circuit continuity.
- If the harness and terminals pass, test the battery temperature sensor using the manufacturer's procedure.
Common fixes
- Dry and clean a moisture-affected connector and restore a secure terminal connection.
- Repair chafed insulation or a signal wire shorted to ground.
- Repair corroded or pushed-back connector terminals.
- Replace the battery temperature sensor if it pulls the signal low despite sound wiring.
Can I keep driving?
If the charging warning is on or charging behavior is abnormal, limit driving because the charging system may undercharge or overcharge the battery. Reduce electrical loads and arrange prompt diagnosis.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.