Particulate Matter Sensor
Measures soot in the exhaust after the particulate filter, so the vehicle can prove the filter is still doing its job. It is easily confused with the differential pressure sensor on the same filter, and it does the opposite thing: the pressure sensor infers how full the filter is from how much it restricts flow, while this one looks at what is getting past.
It works by letting soot accumulate across a pair of electrodes until enough conductive carbon bridges the gap to pass a measurable current, then burning itself clean with a built-in heater and starting again. That cycle explains most of its faults. A sensor whose heater is weak never cleans itself properly, so it measures once and afterwards reports a permanently high value that means nothing — which is why a heater fault usually arrives with a page of other codes from the same sensor, all of which clear together.
It lives under the vehicle in the exhaust stream, where road salt and standing water reach its connector. Corrosion there causes more of its codes than element failure does, and the part is expensive, so the connector is worth eliminating first every time.
Also known as: pm sensor, soot sensor, particulate matter probe, exhaust soot sensor
Referenced by 24 codes
Codes involving this component (24)
- P226D Particulate Filter Deteriorated/Missing Substrate Bank 1 High
- P24AE Particulate Matter Sensor Circuit Moderate
- P24AF Particulate Matter Sensor Circuit Range/Performance Moderate
- P24B0 Particulate Matter Sensor Circuit Low Moderate
- P24B1 Particulate Matter Sensor Circuit High Moderate
- P24B2 Particulate Matter Sensor Circuit Intermittent Moderate
- P24B5 Particulate Matter Sensor Heater Control Circuit Low Moderate
- P24B6 Particulate Matter Sensor Heater Control Circuit High Moderate
- P24B7 Particulate Matter Sensor Heater Resistance Moderate
- P24C7 Particulate Matter Sensor Temperature Circuit Range/Performance Moderate
- P24D0 Particulate Matter Sensor Supply Voltage Circuit Low Moderate
- P24D1 Particulate Matter Sensor Regeneration Incomplete Moderate
- P24DA Particulate Matter Sensor Exhaust Sample Error Bank 1 Moderate
- U02A3 Lost Communication With Particulate Matter Sensor Moderate
- U05A4 Particulate Matter Sensor Received Invalid Data From Engine Control Module Moderate
- P24B3 Particulate Matter Sensor Heater Control Circuit/Open
- P24B4 Particulate Matter Sensor Heater Control Circuit Range/Performance
- P24C6 Particulate Matter Sensor Temperature Circuit
- P24C8 Particulate Matter Sensor Temperature Circuit Low
- P24C9 Particulate Matter Sensor Temperature Circuit High
- P24CA Particulate Matter Sensor Temperature Circuit Intermittent
- P24FC Particulate Matter Sensor Heater Control Circuit Driver Current/Temperature Too High
- U04A4 Invalid Data Received From Particulate Matter Sensor A
- U04B2 Invalid Data Received From Particulate Matter Sensor B
Other components in Exhaust and Emissions
- Oxygen Sensor 326
- EGR Valve 150
- Catalytic Converter 142
- NOx Sensor 118
- Reductant Injector 107
- Exhaust Gas Temperature Sensor 95
- Reductant Tank 95
- Diesel Particulate Filter 76
- SCR Catalyst 65
- EGR Cooler 62
- Exhaust Gas Differential Pressure Sensor 58
- Fuel Tank Pressure Sensor 58
- Exhaust Pressure Control Valve 56
- Reductant Heater 55
- Reductant Pump 51
- EVAP Vent Valve 43
- Exhaust Aftertreatment Fuel Injector 42
- Charcoal Canister 33
- EGR Position Sensor 32
- Secondary Air Injection Pump 32
- Reductant Temperature Sensor 29
- EVAP Leak Detection Pump 29
- EVAP Purge Valve 27
- Reductant Control Module 24
- Reductant Level Sensor 23
- Secondary Air Switching Valve 22
- EGR Temperature Sensor 21
- Secondary Air Check Valve 21
- Catalyst Heater 20
- Catalyst Temperature Sensor 20
- Fuel Filler Cap 18
- EGR Cooler Bypass Valve 16
- Reductant Quality Sensor 16
- Exhaust Back Pressure Sensor 15
- Purge Flow Sensor 13
- Direct Ozone Reduction Catalyst 13
- EGR Vacuum Solenoid 9
- Fuel Vapour Temperature Sensor 5
- Fuel Additive Control Module 4
- Fuel Additive Tank 4
Information, not instruction
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