P221D
Reductant Heater B Current Too High
This code indicates reductant heater b current too high. It relates to the throttle actuator / turbocharger / boost control and may affect performance, emissions, or drivability depending on the exact failure.
Reductant Heater B Current Too High
Common causes
- medium
Faulty sensor or actuator
The component monitored by this code may be worn, failed, or reading out of range.
Typical part cost: $100-400
- medium
Wiring or connector issue
Corroded, damaged, or loose connections can cause circuit or signal faults.
Typical part cost: $100-400
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P221D mean?
P221D means "Reductant Heater B Current Too High". It is a generic OBD-II code that points to a fault in the throttle actuator / turbocharger / boost control.
Can I keep driving with this code?
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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