Technical Description of OBD-II Trouble Code
Circuit for Battery Temperature Sensor
What does that signify?
This generic powertrain diagnostic trouble code is applicable to all OBD-II equipped vehicles, but it is more commonly found in certain Chrysler, Dodge, Jeep, Mitsubishi, and Toyota vehicles.
Although it is a generic code, the specific repair steps may vary depending on the year, make, model, and powertrain configuration of the vehicle.
The Battery Temperature Sensor (BTS) is typically located near the battery or inside the PCM (powertrain control module). The BTS sensor converts the temperature of the air surrounding the battery into an electrical signal for the Powertrain Control Module (PCM).
The PCM uses this voltage signal to determine the amount of voltage the battery will receive while it is being charged, based on the localized temperatures. This code is triggered if this input does not match the normal engine operating conditions stored in the PCM’s memory, even for a brief moment, as demonstrated by this diagnostic trouble code. It also checks the voltage signal from the BTS sensor to ensure it is correct when the key is initially turned on.
Code P0515 indicates a general malfunction, which could be caused by mechanical issues (physical damage to the sensor itself, resulting in an electrical fault) or electrical issues related to the BTS sensor circuit. These issues should not be overlooked during the troubleshooting stage, especially when dealing with an intermittent problem.
The troubleshooting steps may vary depending on the manufacturer, type of BTS sensor, and wire colors. An example of a battery temperature sensor is shown here:
What is the severity of this DTC?
In these cases, the severity is not high. Since they are electrical failures, the PCM can compensate adequately for them.
What are some of the symptoms of the code?
The symptoms of a P0515 trouble code may include:
What are some of the common causes of the code?
The causes of this P0515 code may include:
What are some P0515 troubleshooting steps?
A good starting point is always to check for technical service bulletins (TSB) for your vehicle. Your issue may be a known problem with a known solution provided by the manufacturer, which can save you time and money during diagnosis.
Next, locate the battery temperature sensor on your vehicle. This sensor is usually located near the battery or inside the PCM. Once located, visually inspect the connector and wiring. Look for any signs of scraping, rubbing, bare wires, burn spots, or melted plastic. Disconnect the connector and carefully examine the terminals (the metal parts) inside the connector. Check for any signs of burning or green tint indicating corrosion. If cleaning of the terminals is necessary, use electrical contact cleaner and a plastic bristle brush. Allow them to dry and apply electrical grease to the contact points.
If you have a scan tool, clear the diagnostic trouble codes from the memory and see if the P0515 code returns. If it does not, then the issue was most likely related to the connections.
If the P0515 code does return, you will need to test the BTS sensor and its associated circuits. With the key off, disconnect the electrical connector at the BTS sensor. Connect the black lead of a Digital Voltmeter to the ground terminal at the BTS sensor wiring harness connector. Connect the red lead of the Digital Voltmeter to the signal terminal at the BTS sensor wiring harness connector. Turn the key on, but keep the engine off. Check the manufacturer’s specifications; the voltmeter should read 5 volts. If it does not, repair the signal or ground wire, or replace the PCM.
If the previous test passed and you continue to receive a P0515 code, it most likely indicates a failed BTS sensor. However, a failed PCM cannot be ruled out until the BTS sensor has been replaced. If you are unsure, seek assistance from a trained automotive diagnostician. PCMs must be programmed or calibrated to the vehicle in order to be installed correctly.
