Diesel Exhaust Fluid Tank Level Sensor: Notes

DESCRIPTION AND OPERATION 

DESCRIPTION 

• The Diesel Exhaust Fluid (DEF) Tank Level Sensor and Temperature Sensor used to measure the fluid level of the tank and the temperature of the fluid in the DEF tank. None of these components are serviceable and if tank level sensor or temperature sensor fail, a NEW  DEF tank needs to be installed.

OPERATION 

• The DEF tank level sensor and temperature sensor used to measure the fluid level of the tank and the temperature of the fluid in the DEF tank. Neither of these components are serviceable separately from the DEF tank. If the tank level sensor or temperature sensor fail, a NEW  DEF tank must be installed.
• The DEF tank level sensor and DEF tank temperature sensor are a combined in one circuit to measure the level and temperature of the fluid inside the DEF Tank. This circuit is used transmit a multiplexed PWM signal from the tank to the Powertrain Control Module (PCM). This one circuit carries three pieces of information: The DEF tank (Measured by using ultrasonic transducer reporting ultrasonic waves reflected/echoed by the fluid surface), the DEF temperature, and the DEF Level/Temperature Sensor status.