The B1948 code is a manufacturer-specific body code related to the climate control system. In this case, the engine control module (ECM) has detected a fault or a short to ground in the circuit for the climate control water temperature sensor.
A code B1948 will be stored when the ECM detects a coolant temperature signal circuit fault between the instrument pack and the air conditioning / climate control module (A/CCM). The A/CCM receives an engine coolant temperature voltage signal from the instrument pack.
The A/CCM monitors the engine coolant temperature circuit for open circuit, high resistance and short circuit conditions. If a fault is present, a DTC will be flagged. If a circuit fault occurs between the coolant temperature sensor and the instrument pack, the instrument pack output will default to a voltage equal to 68-degrees Fahrenheit. If a circuit fault occurs between the instrument pack and the A/CCM, the A/CCM will substitute a default value of 169-degrees Fahrenheit.
Several problems may cause a B1948 code including:
Symptoms of a B1948 code may include: * Check engine or warning light may illuminate * The air condition/climate control system may not function correctly (for example, blowing warm air only)
A mechanic may use several methods to diagnose a B1948 trouble code, including: * Utilize an OBD-II scanner to check for a stored B1948 trouble code * Visually inspect wiring and related electrical components for damage or defects * Visually inspect for any leaks in the A/CCM system * Check operation of pressured air conditioning system * Check the fuse for the heater valve to see if blown or damaged * Check the connection to the heater valve for damage or loose connectors or corrosion on the valve itself * Check the evaporator discharge temperature sensor(s) for damage or defect * Test the voltage, current, and resistance on the heater valve
Because a 2018 Dodge Durango 's safe driving operation will not be impacted due to faults that store a B1948 code, this code is not considered a serious code. When this code appears, it is recommended to take your 2018 Dodge Durango to your local service center or mechanic for repair and diagnosis as soon as possible.
Several repairs can fix a B1948 trouble code and include: