What are the common causes of P209F?

A failing reductant tank heater. Corrosion or damage in the tank heater control wiring. A failed reductant tank temperature sensor. Low battery voltage affecting the heater control module. A failing heater control module.

Check battery voltage and charge or replace the battery if it is low. Inspect the reductant tank heater and its wiring for damage. Test the tank heater control circuit for opens and shorts. Read reductant tank temperature data with a scan tool. Replace the tank heater or temperature sensor if faulty. Clear the code and retest.

P209F

Reductant Tank Heater Control Circuit Performance

System: Fuel and air metering (P code)
Lamp: Check Engine Light
Category: Powertrain - Fuel/Air Metering

What it means

P209F means Reductant Tank Heater Control Circuit Performance.

Check these first

A failing reductant tank heater
Corrosion or damage in the tank heater control wiring
A failed reductant tank temperature sensor
Low battery voltage affecting the heater control module
A failing heater control module

What to do next

Check battery voltage and charge or replace the battery if it is low
Inspect the reductant tank heater and its wiring for damage
Test the tank heater control circuit for opens and shorts
Read reductant tank temperature data with a scan tool
Replace the tank heater or temperature sensor if faulty
Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.