P0410
Secondary Air Injection System Malfunction
When a vehicle powertrain module registers the fault code P0410, it points directly to an internal system malfunction identified as "Secondary Air Injection System Malfunction". Operating your engine under this condition may degrade long-term fuel maps.
Driver's Summary
Storing code P0410 is your car's way of telling you something is wrong with the secondary air injection system malfunction. On the road, this usually shows up as check engine light, hesitation on cold start. Low severity — the car drives normally, but the fault should be diagnosed and resolved within the next few weeks.
Symptoms
Check engine light, hesitation on cold start
Common Causes
- Failed smog pump (air injection pump)
- Water intrusion in air pump
- Faulty air injection check valve
- Blown air pump relay or fuse
How to Fix
- 1 Test and replace air injection pump
- 2 Replace rusted check valves
- 3 Check and replace system fuses and relays
- 4 Inspect air hoses for leaks
Technical Explanation
The PCM triggers P0410 after its internal monitoring routine detects that a specific circuit or sensor has exceeded its acceptable operating range. The PCM commands the relevant emission control valve or solenoid and then verifies system response through a dedicated feedback mechanism — either a position sensor, a downstream pressure sensor, or changes in O2 sensor activity patterns. After two failed drive cycles, the code transitions from a pending to a confirmed DTC, and the PCM activates the MIL. Clearing the code without repairing the fault will result in re-illumination within one to two complete drive cycles.
Is It Safe to Drive?
This code won't strand you, but it shouldn't be ignored indefinitely. The failed smog pump (air injection pump) issue identified by P0410 can mask other developing problems and will cause an automatic emissions test failure in most states.
Mechanic's Pro Tip
For P0410, test the solenoid's coil resistance with a multimeter before ordering parts — most solenoids should read between 14 and 40 ohms; an open (infinite resistance) or short (near zero) confirms it's failed electrically. Also verify the PCM is commanding the solenoid by backprobing the connector with a test light during the relevant operating condition — if there's no command signal, the fault is in the PCM or wiring, not the solenoid itself.
Relay/Fuse: $50; Air Pump replacement: $300 - $600