P0516 means the powertrain control module has detected a voltage signal from the battery temperature sensor that is lower than the calibrated range. This typically indicates the sensor or its circuit is reading near zero volts, often due to an internal short or a short to ground. The PCM uses this data to help regulate charging voltage, so an inaccurate signal can disrupt battery management.
The internal thermistor can short or drift out of specification, producing a permanently low signal voltage that the PCM interprets as an implausible temperature.
Chafed, melted, or pinched wiring can allow the sensor signal wire to contact the vehicle frame or another ground path, pulling the circuit voltage to near zero.
Moisture, salt, or debris inside the sensor or harness connector can bridge terminals or degrade pin integrity, creating a low-resistance path that mimics a short.
Impact, improper routing, or a dislodged sensor can allow the component or its wiring to touch metal surfaces, altering circuit resistance and signal voltage.
A rare malfunction in the control module’s internal pull-up or monitoring circuit can set this code, but this should only be considered after the sensor and wiring have been thoroughly tested and verified good.
Short trips are generally acceptable, but prolonged operation can cause improper charging regulation, which may stress the battery and alternator over time.
No. A failed PCM is very uncommon for this code. The vast majority of cases are caused by a failed sensor, a wiring short, or a connector issue. The control module should only be replaced after thorough testing proves it is at fault.
Usually not. This code points to the temperature sensor circuit, not the battery’s internal condition. However, if the sensor is integrated into a battery-monitoring component, that specific part may need service.
The sensor fault itself does not create a parasitic drain, but incorrect temperature data can cause the charging system to undercharge or overcharge, which can reduce battery life or eventually lead to a no-start condition.