What are the common causes of P202A?

An open in the reductant tank heater control circuit. A failed reductant tank heater element. A backed out pin at the heater connector. Chafed wiring along the heater harness.

Command the reductant tank heater with a scan tool. Test the heater circuit for an open. Measure the heater element resistance. Check the heater connector pins. Replace the reductant tank heater if the circuit tests good. Clear the code and retest.

P202A

Reductant Tank Heater Control Circuit/Open

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

What it means

P202A means Reductant Tank Heater Control Circuit/Open.

Check these first

An open in the reductant tank heater control circuit
A failed reductant tank heater element
A backed out pin at the heater connector
Chafed wiring along the heater harness

What to do next

Command the reductant tank heater with a scan tool
Test the heater circuit for an open
Measure the heater element resistance
Check the heater connector pins
Replace the reductant tank heater if the circuit tests good
Clear the code and retest

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Updated

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