P212B — Throttle Position Sensor/Switch "G" Circuit Range/Performance

P212B — Throttle Position Sensor/Switch "G" Circuit Range/Performance. A fault in the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Typical causes: contaminated or failed MAF/MAP sensor, wiring or connector faults in the throttle circuit, intake air leaks after the MAF sensor.

powertrain (engine/transmission)

Is it safe to drive?

Drive with caution Drive with caution. Many throttle faults put the car into limp mode with limited power — enough to reach a shop, not for highway trips. If the engine stalls or the pedal stops responding, do not drive.

How to diagnose with an OBD scanner

  1. Read the code and freeze frame Connect an OBD2 scanner, confirm P212B is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
  2. Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
  3. Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the throttle and intake air metering for damage, corrosion, chafing or poor contact.
  4. Subsystem check Compare the throttle position sensor/switch "G" live reading against a known-good reference (specification or a correlated sensor) under the conditions from the freeze frame.
  5. Subsystem check Inspect and clean the throttle body; check that the plate moves freely.
  6. Subsystem check Watch throttle position and MAF/MAP readings in live data while pressing the pedal — values should change smoothly.
  7. Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P212B does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for P212B (parts and labor, USD, independent shop rates): Replace the MAF or MAP sensor: $150–$400; Clean the throttle body: $80–$200; Replace the throttle body assembly: $250–$700. Overall, fixing P212B usually costs between $80 and $700. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

Will P212B clear itself?

Sometimes P212B clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

How do I diagnose P212B myself?

Start with a scan: confirm P212B, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the throttle position sensor/switch "G", and verify the suspect component against live data before buying parts.

How much does it cost to fix P212B?

Replace the MAF or MAP sensor — $150–$400; Clean the throttle body — $80–$200; Replace the throttle body assembly — $250–$700. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.

What are the symptoms of P212B?

Drivers most often notice: limp-home mode with reduced power, stalling when coming to a stop, unstable or high idle, Check Engine Light on.

Is it safe to drive with P212B?

Drive with caution. Many throttle faults put the car into limp mode with limited power — enough to reach a shop, not for highway trips. If the engine stalls or the pedal stops responding, do not drive.

What does P212B mean?

P212B (Throttle Position Sensor/Switch "G" Circuit Range/Performance) is stored when self-diagnostics detect abnormal readings or behaviour of the throttle and intake air metering. It belongs to the powertrain (engine/transmission) category.

“Range/performance” means the signal from the throttle position sensor/switch "G" is electrically valid but does not match what the module expects for current operating conditions. The wiring is usually intact; the problem is a degraded component, a drifted sensor or a mechanical fault upstream.

The module monitors this system continuously while driving. When readings fall outside the expected range for a defined number of drive cycles, it stores P212B and switches on the warning light. Freeze frame data saved with the code shows the exact conditions — rpm, load, temperature, speed — at the moment the fault was detected, which is the best starting point for diagnosis.

What causes P212B?

  • incorrect calibration after a module update or battery disconnect
  • mechanical fault that the sensor correctly reports
  • degraded or drifting throttle position sensor/switch "G"
  • contaminated or failed MAF/MAP sensor
  • dirty throttle body or stuck throttle plate
  • intake air leaks after the MAF sensor
  • faulty throttle position sensor or pedal sensor

Common symptoms of P212B

  • limp-home mode with reduced power
  • stalling when coming to a stop
  • unstable or high idle
  • Check Engine Light on
  • poor throttle response

How to diagnose P212B

  1. Connect an OBD2 scanner, confirm P212B is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
  2. Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
  3. Visually inspect the wiring harness and connectors related to the throttle and intake air metering for damage, corrosion, chafing or poor contact.
  4. Compare the throttle position sensor/switch "G" live reading against a known-good reference (specification or a correlated sensor) under the conditions from the freeze frame.
  5. Inspect and clean the throttle body; check that the plate moves freely.
  6. Watch throttle position and MAF/MAP readings in live data while pressing the pedal — values should change smoothly.
  7. Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P212B does not return.

How to fix P212B

Start with the cheapest and most common causes before replacing expensive parts:

  • Replace the MAF or MAP sensor — $150–$400
  • Clean the throttle body — $80–$200
  • Replace the throttle body assembly — $250–$700

How much does it cost to fix P212B?

Repair cost depends on which component actually failed. Typical scenarios for P212B (parts and labor, USD, independent shop rates):

  • Replace the MAF or MAP sensor: $150–$400
  • Clean the throttle body: $80–$200
  • Replace the throttle body assembly: $250–$700

Overall, fixing P212B usually costs between $80 and $700. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Can you drive with P212B?

Drive with caution. Many throttle faults put the car into limp mode with limited power — enough to reach a shop, not for highway trips. If the engine stalls or the pedal stops responding, do not drive.

Related OBD2 codes