P20B5: The AdBlue metering unit heater control has a broken or disconnected wire
The AdBlue metering unit heater control has a broken or disconnected wire. It is usually a broken wire, a loose connector or the part itself.
| Code | P20B5 |
|---|---|
| System | Engine and transmission |
| Group | P20xx, Emissions: catalysts and AdBlue |
| Type | Generic: it means the same on every make |
How to read and clear P20B5 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P20B5 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P20B1 The AdBlue heater coolant control valve has a broken or disconnected wire
- P20B2 The AdBlue heater coolant control valve gives readings outside the normal range
- P20B3 The AdBlue heater coolant control valve gives a lower signal than normal
- P20B4 The AdBlue heater coolant control valve gives a higher signal than normal
- P20B6 The AdBlue metering unit heater control gives readings outside the normal range
- P20B7 The AdBlue metering unit heater control gives a lower signal than normal
- P20B8 The AdBlue metering unit heater control gives a higher signal than normal
- P20B9 Reductant (AdBlue) heater A control circuit open or faulty
- P2002 Diesel particulate filter efficiency below threshold (bank 1)
- P2003 Diesel particulate filter efficiency below threshold (bank 2)
- P2004 Intake manifold runner control stuck open (bank 1)
- P2005 Intake manifold runner control stuck open (bank 2)
What does code P20B5 mean?
The AdBlue metering unit heater control has a broken or disconnected wire. It is usually a broken wire, a loose connector or the part itself.
How do you clear P20B5?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P20B5 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
