OBD2 · Powertrain
P24xx codes: emissions — EVAP leak detection, EGR cooling, particulate filter
83 codes in this range, all generic — the same meaning on every make. The systems that clean up exhaust and fuel vapor: exhaust gas recirculation (EGR), secondary air injection, catalytic converter monitoring, the evaporative emissions (EVAP) system with its purge and vent valves — plus exhaust temperature sensors, the particulate filter and some cooling-fan circuits.
What usually causes codes in this area
- A loose or faulty gas cap and other EVAP leaks
- Carbon-clogged EGR valves and passages
- Worn catalytic converters or lazy oxygen sensors
- Stuck purge and vent valves
Can you keep driving?
Most codes here don’t change how the car drives — you can keep going and fix it before the next emissions test. The exceptions are the cooling-fan codes (watch the temperature gauge), particulate-filter codes on diesels, and anything that comes with a flashing lamp or a rotten-egg smell.
All P24xx codes
| Code | Meaning |
|---|---|
| P2400 | Evaporative Emission System Leak Detection Pump Control Circuit/Open |
| P2401 | Evaporative Emission System Leak Detection Pump Control Circuit Low |
| P2402 | Evaporative Emission System Leak Detection Pump Control Circuit High |
| P2403 | Evaporative Emission System Leak Detection Pump Sense Circuit/Open |
| P2404 | Evaporative Emission System Leak Detection Pump Sense Circuit Range/Performance |
| P2405 | Evaporative Emission System Leak Detection Pump Sense Circuit Low |
| P2406 | Evaporative Emission System Leak Detection Pump Sense Circuit High |
| P2407 | Evaporative Emission System Leak Detection Pump Sense Circuit Intermittent/Erratic |
| P2408 | Fuel Cap Sensor/Switch Circuit |
| P2409 | Fuel Cap Sensor/Switch Circuit Range/Performance |
| P240A | Fuel Cap Sensor/Switch Circuit Low |
| P240B | Fuel Cap Sensor/Switch Circuit High |
| P240C | Fuel Cap Sensor/Switch Circuit Intermittent/Erratic |
| P240D | Evaporative Emission System Leak Detection Pump Heater Control Circuit/Open |
| P240E | Evaporative Emission System Leak Detection Pump Heater Control Circuit Low |
| P240F | Evaporative Emission System Leak Detection Pump Heater Control Circuit High |
| P2413 | Exhaust Gas Recirculation System Performance |
| P2414 | O2 Sensor Exhaust Sample Error (Bank 1, Sensor 1) |
| P2415 | O2 Sensor Exhaust Sample Error (Bank 2, Sensor 1) |
| P2416 | O2 Sensor Signals Swapped (Bank 1, Sensor 2/Bank 1, Sensor 3) |
| P2417 | O2 Sensor Signals Swapped (Bank 2, Sensor 2/Bank 2, Sensor 3) |
| P2418 | Evaporative Emission System Switching Valve Control Circuit/Open |
| P2419 | Evaporative Emission System Switching Valve Control Circuit Low |
| P2420 | Evaporative Emission System Switching Valve Control Circuit High |
| P2421 | Evaporative Emission System Vent Valve Stuck Open |
| P2422 | Evaporative Emission System Vent Valve Stuck Closed |
| P2423 | HC Adsorption Catalyst Efficiency Below Threshold (Bank 1) |
| P2424 | HC Adsorption Catalyst Efficiency Below Threshold (Bank 2) |
| P2425 | Exhaust Gas Recirculation Cooling Valve Control Circuit/Open |
| P2426 | Exhaust Gas Recirculation Cooling Valve Control Circuit Low |
| P2427 | Exhaust Gas Recirculation Cooling Valve Control Circuit High |
| P2428 | Exhaust Gas Temperature Too High (Bank 1) |
| P2429 | Exhaust Gas Temperature Too High (Bank 2) |
| P242A | Exhaust Gas Temperature Sensor Circuit (Bank 1, Sensor 3) |
| P242B | Exhaust Gas Temperature Sensor Circuit Range/Performance (Bank 1, Sensor 3) |
| P242C | Exhaust Gas Temperature Sensor Circuit Low (Bank 1, Sensor 3) |
| P242D | Exhaust Gas Temperature Sensor Circuit High (Bank 1, Sensor 3) |
| P242E | Exhaust Gas Temperature Sensor Circuit Intermittent/Erratic (Bank 1, Sensor 3) |
| P242F | Diesel Particulate Filter Restriction - Ash Accumulation |
| P2430 | Secondary Air Injection System Pressure Sensor Circuit (Bank 1) |
| P2431 | Secondary Air Injection System Pressure Sensor Circuit Range/Performance (Bank 1) |
| P2432 | Secondary Air Injection System Pressure Sensor Circuit Low (Bank 1) |
| P2433 | Secondary Air Injection System Pressure Sensor Circuit High (Bank 1) |
| P2434 | Secondary Air Injection System Pressure Sensor Circuit Intermittent/Erratic (Bank 1) |
| P2435 | Secondary Air Injection System Pressure Sensor Circuit (Bank 2) |
| P2436 | Secondary Air Injection System Pressure Sensor Circuit Range/Performance (Bank 2) |
| P2437 | Secondary Air Injection System Pressure Sensor Circuit Low (Bank 2) |
| P2438 | Secondary Air Injection System Pressure Sensor Circuit High (Bank 2) |
| P2439 | Secondary Air Injection System Pressure Sensor Circuit Intermittent/Erratic (Bank 2) |
| P2440 | Secondary Air Injection System Switching Valve Stuck Open (Bank 1) |
| P2441 | Secondary Air Injection System Switching Valve Stuck Closed (Bank 1) |
| P2442 | Secondary Air Injection System Switching Valve Stuck Open (Bank 2) |
| P2443 | Secondary Air Injection System Switching Valve Stuck Closed (Bank 2) |
| P2444 | Secondary Air Injection System Pump Stuck On (Bank 1) |
| P2445 | Secondary Air Injection System Pump Stuck Off (Bank 1) |
| P2446 | Secondary Air Injection System Pump Stuck On (Bank 2) |
| P2447 | Secondary Air Injection System Pump Stuck Off (Bank 2) |
| P2448 | Secondary Air Injection System High Airflow (Bank 1) |
| P2449 | Secondary Air Injection System High Airflow (Bank 2) |
| P244A | Diesel Particulate Filter Differential Pressure Too Low (Bank 1) |
| P244B | Diesel Particulate Filter Differential Pressure Too High (Bank 1) |
| P244C | Exhaust Temperature Too Low For Particulate Filter Regeneration (Bank 1) |
| P244D | Exhaust Temperature Too High For Particulate Filter Regeneration (Bank 1) |
| P2450 | Evaporative Emission System Switching Valve Performance/Stuck Open |
| P2451 | Evaporative Emission System Switching Valve Stuck Closed |
| P2452 | Diesel Particulate Filter Pressure Sensor "A" Circuit |
| P2453 | Diesel Particulate Filter Pressure Sensor "A" Circuit Range/Performance |
| P2454 | Diesel Particulate Filter Pressure Sensor "A" Circuit Low |
| P2455 | Diesel Particulate Filter Pressure Sensor "A" Circuit High |
| P2456 | Diesel Particulate Filter Pressure Sensor "A" Circuit Intermittent/Erratic |
| P2457 | Exhaust Gas Recirculation Cooling System Performance |
| P2458 | Diesel Particulate Filter Regeneration Duration |
| P2459 | Diesel Particulate Filter Regeneration Frequency |
| P245A | Exhaust Gas Recirculation Cooler Bypass Control Circuit/Open |
| P245B | Exhaust Gas Recirculation Cooler Bypass Control Circuit Range/Performance |
| P245C | Exhaust Gas Recirculation Cooler Bypass Control Circuit Low |
| P245D | Exhaust Gas Recirculation Cooler Bypass Control Circuit High |
| P2463 | Diesel Particulate Filter - Soot Accumulation |
| P246E | Exhaust Gas Temperature Sensor Circuit (Bank 1, Sensor 4) |
| P246F | Exhaust Gas Temperature Sensor Circuit Range/Performance (Bank 1, Sensor 4) |
| P2470 | Exhaust Gas Temperature Sensor Circuit Low (Bank 1, Sensor 4) |
| P2471 | Exhaust Gas Temperature Sensor Circuit High (Bank 1, Sensor 4) |
| P2472 | Exhaust Gas Temperature Sensor Circuit Intermittent/Erratic (Bank 1, Sensor 4) |
Read the codes from your own car
Plug an inexpensive Bluetooth LE or Wi-Fi OBD2 adapter into the port under the dashboard, and Brimly on your iPhone reads the stored, pending and permanent codes, explains each one offline and clears them once the fault is fixed. OBD diagnostics are part of Brimly Forever, a one-time purchase.
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