OBD2 Car ScannerWhat does P202B mean?
P202B stands for Reductant Tank Heater Control Circuit Low. The engine computer has found a problem with how fuel and air are measured or mixed. This affects fuel economy, emissions and sometimes how smoothly the engine runs.
Powertrain codes cover the engine, transmission and emissions. When the car's computer sees a reading outside its normal range, it stores this code and may turn on a warning light on the dashboard.
Common causes
- Vacuum or intake air leaks
- Dirty or faulty mass airflow (MAF) sensor
- Faulty oxygen sensor or its wiring
- Fuel pressure problems (pump, filter or regulator)
- Clogged or leaking fuel injectors
What to do
- Read all stored and pending codes with a scanner. Several codes together often point to one cause.
- Note the freeze frame data (speed, temperature, load) recorded when the code was set.
- Inspect the wiring and connectors of the part named in the code for damage, corrosion or looseness.
- Fix the most likely and cheapest cause first, then clear the code and drive to see if it comes back.
Read this code from your own car
Plug in a cheap ELM327 adapter and the app shows every fault code, what it means and how to fix it.
Frequently asked questions
What does P202B mean?
P202B means “Reductant Tank Heater Control Circuit Low”. It belongs to the fuel and air metering group: The engine computer has found a problem with how fuel and air are measured or mixed. This affects fuel economy, emissions and sometimes how smoothly the engine runs.
Is it safe to drive with P202B?
You can usually drive carefully for a short time, but fix it soon to avoid further damage or higher fuel use.
How do I clear P202B?
Fix the cause, then clear the code with an OBD2 scanner or app. If the fault is still there, the code will come back.
Related codes
- P2027Evaporative Emissions (EVAP) Fuel Vapor Temperature Sensor Circuit High Voltage
- P2028Evaporative Emissions (EVAP) Fuel Vapor Temperature Sensor Circuit Intermittent
- P2029Fuel Fired Heater Disabled
- P202AReductant Tank Heater Control Circuit/Open
- P202CReductant Tank Heater Control Circuit High
- P202DReductant Leakage
- P202EReductant Injection Valve Circuit Range/Performance Bank 1 Unit 1
- P202FReductant/Regeneration Supply Control Circuit Range/Performance
Code meanings can vary by manufacturer. This page is general guidance, not a repair manual. Always confirm the cause before replacing parts.