P213B

Gas Recirculation Throttle Control Circuit B Range/Performance

P213B is a generic OBD-II powertrain diagnostic trouble code: Gas Recirculation Throttle Control Circuit B Range/Performance. It is logged by the engine control unit when the throttle monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.

Code
P213B
Group
Powertrain
System
Throttle
Severity
Warning (MIL on)
Need P213B disabled?
RaceTune permanently disables any OBD-II trouble code on supported ECUs — for motorsport, off-road, and export use.

What P213B means

P213B is set when the PCM or aftertreatment control module detects that the voltage on the reductant pump control circuit is higher than the expected upper threshold. While P213A indicates a low or shorted circuit, P213B points to an open circuit, short to power, or driver feedback problem that results in abnormally high voltage on the control line.

In a typical pump control circuit, the module supplies a regulated voltage to drive the pump; when commanded off, the circuit should return to a predictable low voltage. A high circuit fault often means the circuit is open (disconnected pump or broken wire) or that voltage is being fed back from another source. The pump is not operating as intended in either case.

As with all reductant system faults, P213B can initiate a regulatory derate countdown on vehicles designed to enforce emissions compliance. Prompt diagnosis and repair of the circuit fault is essential to restore SCR system function and prevent derate activation.

Common causes

Most-frequently reported root causes when P213B is logged.

  • 1
    Open circuit on the reductant pump control or supply wire.
  • 2
    Disconnected or improperly seated pump connector.
  • 3
    Short to battery voltage on the pump control signal wire.
  • 4
    Failed pump driver circuit in the control module outputting a stuck-high signal.
  • 5
    Broken wire inside the harness with the conductor contacting a voltage supply.
  • 6
    Corroded connector causing loss of continuity on the return circuit.
  • 7
    Relay or fuse supplying pump power failed open, causing unexpected feedback voltage.

Symptoms drivers notice

MIL and DEF or SCR warning light illuminated.
Reductant pump not operating.
No DEF dosing, leading to elevated NOx output.
Possible torque or speed derate warning on the instrument cluster.
Scan tool shows pump commanded on but zero current draw.

How to diagnose P213B

A typical diagnostic flow when this code is present.

  1. 1
    Retrieve all DTCs and note any companion reductant or NOx sensor codes.
  2. 2
    Inspect the reductant pump connector for disconnection, damage, or corrosion.
  3. 3
    Check for an open circuit or short to voltage on the pump control wire using a wiring diagram.
  4. 4
    Verify pump supply voltage and ground at the connector with the ignition on.
  5. 5
    Check for correct pump driver output from the control module with pump disconnected.
  6. 6
    Test pump motor continuity and resistance.
  7. 7
    Repair wiring or replace pump as required, then verify SCR system operation with a scan tool.

Related powertrain codes

Frequently asked questions

What is the difference between P213A and P213B?

P213A indicates the control circuit voltage is too low (short to ground or motor short), while P213B indicates it is too high (open circuit or short to power). Both prevent normal pump operation but require different diagnostic approaches.

Can a disconnected pump connector cause P213B?

Yes. With the pump connector unplugged, the module may detect an open circuit that reads as an abnormally high voltage on its feedback line, triggering the high circuit code.

Will the DEF light come on immediately?

The warning indicator typically illuminates as soon as the fault is confirmed. The regulatory countdown for derate may begin at the same time, depending on the vehicle compliance strategy.

Can I temporarily bypass this fault to drive the vehicle?

No bypass should be attempted. Bypassing SCR system faults risks emissions non-compliance and may accelerate the regulatory derate that limits vehicle operation.

Disabling P213B in software

RaceTune can permanently disable P213B — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.

Permanent
The monitor is disabled in the ECU itself — not just cleared. It cannot return.
Tailored to your file
Each patch is matched to your specific software version — never a one-size-fits-all file.
Reversible
The original file is always preserved. Reflash the stock to return the ECU to factory state.

Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.

Got P213B in your scan?

Upload your ECU file — we'll identify the exact software version and confirm whether a disable is available for your car.

Upload your file