Symptoms

- Engine Light ON (or Service Engine Soon Warning Light) - Possible engine overheating

Possible Causes

- Open or short Battery Temperature Sensor circuit condition - Poor electrical connection for the Battery Temperature Sensor - Faulty Battery Temperature Sensor

Tech Notes

There is a service bulletin for the 2006 Dodge Ram Truck P0514 Dodge Service Bulletin

Description

The Battery Temperature Sensor (BTS) is attached to the battery tray located under the battery. The BTS is used to determine the battery temperature and control battery charging rate. This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. System voltage will be higher at colder temperatures and is gradually reduced at warmer temperatures. The PCM sends 5 volts to the sensor and is grounded through the sensor return line. As temperature increases, resistance in the sensor decreases and the detection voltage at the PCM increases. The BTS is also used for OBD II diagnostics. Certain faults and OBD II monitors are either enabled or disabled, depending upon BTS input (for example, disable purge and enable Leak Detection Pump (LDP) and O2 sensor heater tests). Most OBD II monitors are disabled below 20°F.