OBD Codes List

Diagnostic reference · P24B2

P24B2

Particulate Matter Sensor Circuit Intermittent

System
Auxiliary emission controls (P code)
Lamp
Check Engine Light
Category
Powertrain - Auxiliary Emissions Controls

What it means

P24B2 stands for Particulate Matter Sensor Circuit Intermittent. P24B2 is a P code, so the fault sits in the engine, transmission and emissions systems. For P24B2, the second digit places it in auxiliary emission controls. For P24B2, work through the cause list below, cheapest checks first.

Where it lives

For P24B2, the circuit described runs through the sensor. The description of P24B2 reports a fault at the sensor.

What to check first

For P24B2, check the wiring and connector on this circuit first, since a broken terminal gives the same reading as a failed part.

Check these first

  • P24B2: Carbon buildup or blockage in the EGR, EVAP, or air injection system
  • P24B2: Failed solenoid, valve, or pump in the auxiliary emissions circuit
  • P24B2: Wiring, connector, or fuse fault for the emission component
  • P24B2: Small leaks in vacuum or EVAP lines
  • P24B2: Failing catalytic converter or oxygen sensor reporting incorrectly

What to do next

P24B2 reports from the auxiliary emission controls system. These steps cover P24B2 in general, and the exact cause on your vehicle can differ from the cause named above.

  1. P24B2: Read related codes and freeze frame with an OBD-II scanner
  2. P24B2: Inspect hoses, valves, and solenoids for leaks, cracks, or carbon buildup
  3. P24B2: Smoke test the EVAP or intake system if a leak is suspected
  4. P24B2: Command components on/off with a scan tool and watch them respond
  5. P24B2: Clean or replace the blocked or failed component

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Updated

Generic SAE J2012 definition. Last updated 2026-08-30.